Wednesday, December 20, 2006

Nutrition in toddlers

Am Fam Physician <http://www.aafp.org/afp/20061101/1527.html> November 1 2006;74:1527-32, 1533-4. © 2006 American Academy of Family Physicians. Nutrition in Toddlers, Richard E. Allen, M.D., M.P.H. and Anya L. Myers, R.D., M.SC.

Pada usia 'toddler' seorang anak mengalami transisi dari bayi menjadi anak, demikian pula dietnya berubah dari diet susu menjadi diet anak yang omnivor. Dalam peralihan ini dokter perlu melakukan monitoring pertumbuhan dan indeks massa tubuh untuk menentukan diet yang sehat bagi sang anak.

Pembatasan makanan berlemak dan kolesterol kiranya belum perlu pada anak <2 tahun. Setelah usia 2 tahun dianjurkan konsumsi lemak 30% dari jumlah total kebutuhan kalori per hari, terutama lemak tak jenuh jamak (polyunsaturated fats). Dianjurkan konsumsi susu atau produk olahan susu (dairy product) setidaknya dua sampai tiga kali sehari. Konsumsi pemanis/minuman manis dibatasi 120-180 gram per hari. Penggunaan multivitamin secara rutin tidak perlu. Dianjurkan konsumsi berbagai golongan makanan.

Karena anak cenderung meniru orang tuanya maka parental modeling perlu dalam rangka membentuk kebiasaan makan yang baik bagi sang anak. Tidak ada bukti kuat bahwa obesitas pada usia anak berhubungan dengan obesitas pada usia dewasa, sehingga lebih baik anak tidak kurang gizi daripada khawatir terjadinya obesitas pada usia toddler.

Toddlers make a transition from dependent milk-fed infancy to independent feeding and a typical omnivorous diet. This stage is an important time for physicians to monitor growth using growth charts and body mass index and to make recommendations for healthy eating. Fat and cholesterol restriction should be avoided in children younger than two years. After two years of age, fat should account for 30 percent of total daily calories, with an emphasis on polyunsaturated fats. Toddlers should consume milk or other dairy products two or three times daily, and sweetened beverages should be limited to 4 to 6 ounces of 100 percent juice daily. Vitamin D, calcium, and iron should be supplemented in select toddlers, but the routine use of multivitamins is unnecessary. Food from two of the four food groups should be offered for snacks, and meals should be made up of three of the four groups. Parental modeling is important in developing good dietary habits. No evidence exists that early childhood obesity leads to adult obesity, but physicians should monitor body mass index and make recommendations for healthy eating. The fear of obesity must be carefully balanced with the potential for undernutrition in toddlers. (Am Fam Physician 2006;74:1527-32, 1533-4. Copyright © 2006 American Academy of Family Physicians.)

Tuesday, November 21, 2006

Diet Rendah Karbohidrat dan Risiko Penyakit Jantung Koroner untuk Wanita

Diet rendah karbohidrat (low carb) banyak digunakan untuk menurunkan berat badan dan mencegah obesitas. Bagaimana efek diet low carb terhadap risiko penyakit jantung koroner (PJK)?

Penelitian yang melibatkan >82 ribu subyek dan difollow-up selama 20 tahun, menyimpulkan terhadap risiko terjadinya PJK, diet low carb ataupun diet low fat ternyata tidak berbeda. Kedua jenis diet - low carb maupun low fat - mempunyai kelebihan dan kekurangan masing2.

Temuan terpenting adalah bahwa dengan memperbanyak sayuran dalam diet (sebagai sumber protein nabati dan lemak nabati) risiko PJK dapat diturunkan sebesar 30%. Sebaliknya konsumsi karbohidrat ber-indeks glisemik rendah (misalnya gula) akan meningkatkan risiko PJK.

New England Journal of Medicine number 19, Volume 355:1991-2002. Low-Carbohydrate-Diet Score and the Risk of Coronary Heart Disease in Women. Thomas L. Halton, Sc.D., Walter C. Willett, M.D., Dr.P.H., Simin Liu, M.D., Sc.D., JoAnn E. Manson, M.D., Dr.P.H., Christine M. Albert, M.D., M.P.H., Kathryn Rexrode, M.D., and Frank B. Hu, M.D., Ph.D.

ABSTRACT

Background Low-carbohydrate diets have been advocated for weight loss and to prevent obesity, but the long-term safety of these diets has not been determined. Methods We evaluated data on 82,802 women in the Nurses' Health Study who had completed a validated food-frequency questionnaire. Data from the questionnaire were used to calculate a low-carbohydrate-diet score, which was based on the percentage of energy as carbohydrate, fat, and protein (a higher score reflects a higher intake of fat and protein and a lower intake of carbohydrate). The association between the low-carbohydrate-diet score and the risk of coronary heart disease was examined. Results During 20 years of follow-up, we documented 1994 new cases of coronary heart disease. After multivariate adjustment, the relative risk of coronary heart disease comparing highest and lowest deciles of the low-carbohydrate-diet score was 0.94 (95% confidence interval [CI], 0.76 to 1.18; P for trend=0.19). The relative risk comparing highest and lowest deciles of a low-carbohydrate-diet score on the basis of the percentage of energy from carbohydrate, animal protein, and animal fat was 0.94 (95% CI, 0.74 to 1.19; P for trend=0.52), whereas the relative risk on the basis of the percentage of energy from intake of carbohydrates, vegetable protein, and vegetable fat was 0.70 (95% CI, 0.56 to 0.88; P for trend=0.002). A higher glycemic load was strongly associated with an increased risk of coronary heart disease (relative risk comparing highest and lowest deciles, 1.90; 95% CI, 1.15 to 3.15; P for trend=0.003).

Conclusions Our findings suggest that diets lower in carbohydrate and higher in protein and fat are not associated with increased risk of coronary heart disease in women. When vegetable sources of fat and protein are chosen, these diets may moderately reduce the risk of coronary heart disease.

Source Information From the Departments of Nutrition (T.L.H., W.C.W., F.B.H.) and Epidemiology (W.C.W., J.E.M., F.B.H.), Harvard School of Public Health, Boston; the Department of Epidemiology, University of California, Los Angeles, School of Public Health, Los Angeles (S.L.); and the Division of Preventive Medicine (J.E.M., C.M.A., K.R.), the Channing Laboratory (W.C.W., J.E.M., K.R., F.B.H.), and the Cardiovascular Division (C.M.A.), Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston.

Friday, November 10, 2006

Untung Rugi Konsumsi Seafood

Para peneliti dari Harvard ingin mengetahui keuntungan dan kerugian konsumsi seafood.

Ternyata konsumsi seafood (terutama ikan yang kaya asam lemak omega-3 berupa DHA maupun EPA) sebanyak 1-2 porsi tiap minggu dapat menurunkan angka kematian penyakit jantung koroner sebesar 36%.

DHA mendukung perkembangan awal sel2 saraf, sehingga ibu hamil dan menyusui dianjurkan untuk konsumsi seafood 2 porsi tiap minggu. Kontaminasi metil-merkuri sebaliknya menghambat perkembangan sel2 saraf, namun pengaruh metil-merkuri untuk orang dewasa kurang nyata.

Dianjurkan mengkonsumsi beragam jenis seafood.

Kadar kontaminasi dioxin dan polychlorinated biphenyls terdeteksi rendah, sehingga potensi karsinogeniknya juga rendah.

Disimpulkan bahwa keuntungan konsumsi beragam seafood lebih besar dibanding efek negatifnya, termasuk untuk kelompok wanita usia subur.

Catatan untuk seafood dari perairan dengan tingkat kontaminasi lebih tinggi, kesimpulan di atas mungkin tidak berlaku.

Abstract

JAMA <http://jama.ama-assn.org/cgi/content/abstract/296/15/1885?etoc><http://jama .ama-assn.org/cgi/content/abstract/296/15/1885?etoc> 2006;296:1885-1899. Vol. 296 No. 15, October 18, 2006 © 2006 American Medical Association. Fish Intake, Contaminants, and Human Health: Evaluating the Risks and the Benefits. Dariush Mozaffarian, Eric B. Rimm.

Context Fish (finfish or shellfish) may have health benefits and also contain contaminants, resulting in confusion over the role of fish consumption in a healthy diet. Evidence Acquisition We searched MEDLINE, governmental reports, and meta-analyses, supplemented by hand reviews of references and direct investigator contacts, to identify reports published through April 2006 evaluating (1) intake of fish or fish oil and cardiovascular risk, (2) effects of methylmercury and fish oil on early neurodevelopment, (3) risks of methylmercury for cardiovascular and neurologic outcomes in adults, and (4) health risks of dioxins and polychlorinated biphenyls in fish. We concentrated on studies evaluating risk in humans, focusing on evidence, when available, from randomized trials and large prospective studies. When possible, meta-analyses were performed to characterize benefits and risks most precisely. Evidence Synthesis Modest consumption of fish (eg, 1-2 servings/wk), especially species higher in the n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), reduces risk of coronary death by 36% (95% confidence interval, 20%-50%; P<.001) and total mortality by 17% (95% confidence interval, 0%-32%; P = .046) and may favorably affect other clinical outcomes. Intake of 250 mg/d of EPA and DHA appears sufficient for primary prevention. DHA appears beneficial for, and low-level methylmercury may adversely affect, early neurodevelopment. Women of childbearing age and nursing mothers should consume 2 seafood servings/wk, limiting intake of selected species. Health effects of low-level methylmercury in adults are not clearly established; methylmercury may modestly decrease the cardiovascular benefits of fish intake. A variety of seafood should be consumed; individuals with very high consumption (5 servings/wk) should limit intake of species highest in mercury levels. Levels of dioxins and polychlorinated biphenyls in fish are low, and potential carcinogenic and other effects are outweighed by potential benefits of fish intake and should have little impact on choices or consumption of seafood (women of childbearing age should consult regional advisories for locally caught freshwater fish). Conclusions For major health outcomes among adults, based on both the strength of the evidence and the potential magnitudes of effect, the benefits of fish intake exceed the potential risks. For women of childbearing age, benefits of modest fish intake, excepting a few selected species, also outweigh risks.

Author Affiliations: Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, and Harvard Medical School; and Departments of Epidemiology and Nutrition, Harvard School of Public Health, Boston, Mass.

Thursday, November 02, 2006

Kopi, diabetes dan berat badan

Beberapa penelitian epidemiologi menyimpulkan bahwa kopi (baik caffeinated maupun decaffeinated) dapat mengurangi risiko diabetes. Ini mungkin berhubungan dengan penurunan berat badan. Penurunan berat badan diduga berhubungan dengan kandungan kafein dan zat2 lain dalam kopi (chlorogenic acid dan quinides). Namun kopi dapat menyebabkan kenaikan tekanan darah akut sehingga ditakutkan akan meningkatkan risiko penyakit kardiovaskuler. Satu penelitian singkat menyimpulkan bahwa kopi decaffeinated tidak menaikan tekanan darah. Dengan demikian konsumsi kopi decaffeinated lebih aman dan tetap dapat mengurangi risiko diabetes.

Abstract

American Journal of Clinical Nutrition, Vol. 84, No. 4, 682-693, October 2006 © 2006 American Society for Nutrition. Coffee, diabetes, and weight control. James A Greenberg, Carol N Boozer and Allan Geliebter. From the Department of Health and Nutrition Sciences, Brooklyn College, City University of New York, New York NY (JAB), and the Department of Medicine, Columbia University and New York Obesity Research Center, St Luke's-Roosevelt Hospital Center, New York, NY (NB and AG) Several prospective epidemiologic studies over the past 4 y concluded that ingestion of caffeinated and decaffeinated coffee can reduce the risk of diabetes. This finding is at odds with the results of trials in humans showing that glucose tolerance is reduced shortly after ingestion of caffeine or caffeinated coffee and suggesting that coffee consumption could increase the risk of diabetes. This review discusses epidemiologic and laboratory studies of the effects of coffee and its constituents, with a focus on diabetes risk. Weight loss may be an explanatory factor, because one prospective epidemiologic study found that consumption of coffee was followed by lower diabetes risk but only in participants who had lost weight. A second such study found that both caffeine and coffee intakes were modestly and inversely associated with weight gain. It is possible that caffeine and other constituents of coffee, such as chlorogenic acid and quinides, are involved in causing weight loss. Caffeine and caffeinated coffee have been shown to acutely increase blood pressure and thereby to pose a health threat to persons with cardiovascular disease risk. One short-term study found that ground decaffeinated coffee did not increase blood pressure. Decaffeinated coffee, therefore, may be the type of coffee that can safely help persons decrease diabetes risk. However, the ability of decaffeinated coffee to achieve these effects is based on a limited number of studies, and the underlying biological mechanisms have yet to be elucidated.

Tuesday, October 31, 2006

Are vegetables better food for brain?

Untuk meneliti hubungan antara perubahan fungsi kognitif dengan konsumsi buah dan sayuran di kalangan manula, para ahli melakukan penelitian kohort prospektif dengan 3.718 subyek berusia >65 tahun.

Rerata skor kognitif pada awal penelitian adalah 0,18 dan terjadi penurunan sebesar 0,04 standard unit pertahun. Kelompok yang paling sedikit makan sayur ternyata mengalami penurunan fungsi kognitif lebih cepat dibanding kelompok yang paling banyak makan sayur. Mereka yang makan sayur 3-4 porsi perhari mengalami penurunan skor kognitif 40% lebih lambat dibanding mereka yang makan sayur kurang dari 1 porsi perhari. Sedangkan tingkat konsumsi buah tidak berhubungan dengan perubahan kognitif.

Kesimpulan banyak konsumsi sayuran dapat menghambat penurunan fungsi kognitif pada manula.

Abstract

Neurology 2006;67:1370-1376 October 24 2006 © 2006 American Academy of Neurology. Associations of vegetable and fruit consumption with age-related cognitive change M. C. Morris, ScD, D. A. Evans, MD, C. C. Tangney, PhD, J. L. Bienias, ScD and R. S. Wilson, PhD

Objective: To examine the association between rates of cognitive change and dietary consumption of fruits and vegetables among older persons. Methods: The authors conducted a prospective cohort study of 3,718 participants, aged 65 years and older of the Chicago Health and Aging Project. Participants completed a food frequency questionnaire and were administered at least two of three cognitive assessments at baseline, 3-year, and 6-year follow-ups. Cognitive function was measured using the average z-score of four tests: the East Boston Tests of immediate memory and delayed recall, the Mini-Mental State Examination, and the Symbol Digit Modalities Test. Results: The mean cognitive score at baseline for the analyzed cohort was 0.18 (range: -3.5 to 1.6), and the overall mean change in score per year was a decline of 0.04 standardized units. In mixed effects models adjusted for age, sex, race, and education, compared with the rate of cognitive decline among persons in the lowest quintile of vegetable intake (median of 0.9 servings/day), the rate for persons in the fourth quintile (median, 2.8 servings/day) was slower by 0.019 standardized units per year (p = 0.01), a 40% decrease, and by 0.018 standardized units per year (p = 0.02) for the fifth quintile (median, 4.1 servings/day), or a 38% decrease in rates. The association remained significant (p for linear trend = 0.02) with further control of cardiovascular-related conditions and risk factors. Fruit consumption was not associated with cognitive change. Conclusion: High vegetable but not fruit consumption may be associated with slower rate of cognitive decline with older age.

From Rush Institute for Healthy Aging (M.C.M., D.A.E., J.L.B.), Department of Preventive Medicine (M.C.M., J.L.B.), Department of Internal Medicine (M.C.M., D.A.E.), Department of Clinical Nutrition (C.C.T.), Rush Alzheimer's Disease Center (R.S.W.), Department of Neurological Sciences (R.S.W.), and Department of Psychology (R.S.W.), Rush University Medical Center, Chicago, IL.

Monday, October 16, 2006

Makronutrien sebagai Prediktor Perubahan Lingkar Pinggang

Sering kali kita bertanya-tanya apakah bahan makanan atau minuman tertentu menyebabkan perut menjadi buncit? Temuan penelitian berikut ini sangat menarik.

Para ahli dari Denmark mencari hubungan antara asupan energi/kalori, asupan makronutrien tertentu dan subgrup-nya terhadap perubahan lingkar pinggang 5 tahun kemudian, dengan melakukan studi kohort atas lebih dari 40 ribu pria dan wanita berusia 50-64 tahun.

Ternyata protein menunjukkan asosiasi terbalik dengan perubahan lingkar pinggang. Artinya semakin besar konsumsi protein, semakin kecil perubahan lingkar pinggang. Demikian juga untuk buah dan sayuran. Pada wanita terdapat asosiasi positif antara asupan karbohidrat refined, kentang dan gula. Lemak nabati dan alkohol juga ber-asosiasi positif. Artinya semakin besar konsumsi bahan makanan tersebut semakin besar pula perubahan lingkar pinggang dalam waktu 5 tahun.

American Journal of Clinical Nutrition, Vol. 84, No. 4, 789-797, October 2006 © 2006

Intake of macronutrients as predictors of 5-y changes in waist circumference

Jytte Halkjær, Anne Tjønneland, Birthe L Thomsen, Kim Overvad and Thorkild IA Sørensen From the Danish Epidemiology Science Centre, Institute of Preventive Medicine, Copenhagen University Hospital, Copenhagen, Denmark (JH and TIAS); The Danish Cancer Society, Institute of Cancer Epidemiology, Copenhagen, Denmark (JH, AT, and BLT); and the Department of Clinical Epidemiology, Aalborg Hospital, Aarhus University Hospital, Aalborg, Denmark (KO)

Background:The diet may influence the development of abdominal obesity, but the few studies that have prospectively examined the relations between diet and changes in waist circumference (WC) have given inconsistent results. Objective:Associations between total energy intake, energy intake from macronutrients, and energy intake from macronutrient subgroups based on different food sources and 5-y differences in WC (DWC) were investigated. Design:A Danish cohort of 22.570 women and 20.126 men aged 50-64 y with baseline data on WC, diet, BMI, and potential confounders reported their WC 5 y later. Associations of baseline diet with DWC were assessed by multiple linear regression analysis. Results:Neither total energy intake nor energy intake from each of the macronutrients was associated with DWC, except for an inverse association with protein, especially animal protein. In women, positive associations with DWC were seen for carbohydrate from refined grains and potatoes and from foods with simple sugars, whereas carbohydrate from fruit and vegetables was inversely associated and significantly different from any other carbohydrate subgroup. The results for men resembled those for women, although none were significant. Vegetable fat was positively associated with DWC for both men and women in a combined analysis. A U-shaped association between alcohol from wine and DWC was present for both sexes, and alcohol from spirits was positively associated with DWC in women. Conclusions:Although no significant associations with total energy or energy from fat, carbohydrate, or alcohol were observed, protein intake was inversely related to DWC, and some macronutrient subgroups were significantly associated with DWC.

Wednesday, October 11, 2006

Diet Mediterrania dapat mencegah Alzheimer

Para ahli meneliti hubungan antara diet mediterrania dan penyakit Alzheimer dengan melakukan studi kasus kontrol.

Hasil penelitian mendapatkan bahwa penganut diet mediterrania mempunyai risiko lebih rendah untuk terkena penyakit Alzheimer (odds ratio, 0.76; 95% confidence interval, 0.67-0.87; P<.001). Namun belum jelas mekanisme yang mempengaruhi hal tersebut.

Abstract

Mediterranean Diet, Alzheimer Disease, and Vascular Mediation

Nikolaos Scarmeas, MD; Yaakov Stern, PhD; Richard Mayeux, MD; Jose A. Luchsinger, MD Arch Neurol. 2006;63:(doi:10.1001/archneur.63.12.noc60109).

Objectives To examine the association between the Mediterranean diet (MeDi) and Alzheimer disease (AD) in a different AD population and to investigate possible mediation by vascular pathways. Design, Setting, Patients, and Main Outcome Measures A case-control study nested within a community-based cohort in New York, NY. Adherence to the MeDi (0- to 9-point scale with higher scores indicating higher adherence) was the main predictor of AD status (194 patients with AD vs 1790 nondemented subjects) in logistic regression models that were adjusted for cohort, age, sex, ethnicity, education, apolipoprotein E genotype, caloric intake, smoking, medical comorbidity index, and body mass index (calculated as weight in kilograms divided by height in meters squared). We investigated whether there was attenuation of the association between MeDi and AD when vascular variables (stroke, diabetes mellitus, hypertension, heart disease, lipid levels) were simultaneously introduced in the models (which would constitute evidence of mediation). Results Higher adherence to the MeDi was associated with lower risk for AD (odds ratio, 0.76; 95% confidence interval, 0.67-0.87; P<.001). Compared with subjects in the lowest MeDi tertile, subjects in the middle MeDi tertile had an odds ratio of 0.47 (95% confidence interval, 0.29-0.76) and those at the highest tertile an odds ratio of 0.32 (95% confidence interval, 0.17-0.59) for AD (P for trend <.001). Introduction of the vascular variables in the model did not change the magnitude of the association. Conclusions We note once more that higher adherence to the MeDi is associated with a reduced risk for AD. The association does not seem to be mediated by vascular comorbidity. This could be the result of either other biological mechanisms (oxidative or inflammatory) being implicated or measurement error of the vascular variables. Published online October 9, 2006 (doi:10.1001/archneur.63.12.noc60109). Author Affiliations: Taub Institute for Research on Alzheimer's Disease and the Aging Brain (Drs Scarmeas, Stern, Mayeux, and Luchsinger); Gertrude H. Sergievsky Center (Drs Scarmeas, Stern, and Mayeux); and Departments of Neurology (Drs Scarmeas, Stern, and Mayeux) and Medicine (Dr Luchsinger), Columbia University, New York, NY.

Friday, October 06, 2006

Sterol nabati dalam jus jeruk dapat memperbaiki profil lipid dan menurunkan kadar CRP

Pernah saya menulis tentang sterol nabati yang bisa memperbaiki profil lipid. Sterol nabati biasanya dicampur dalam lemak. Dalam penelitian ini sterol nabati dicampurkan dalam jus jeruk rendah kalori.

Ternyata penambahan sterol nabati dapat menurunkan kadar kolesterol total dan LDL sebesar hampir 10%, sekaligus meningkatkan kadar kolesterol HDL. Selain memperbaiki profil lipid, kadar CRP (penanda proses inflamasi kardiovaskuler) juga dapat diturunkan sampai 12%.

Hasil yang sangat positif dapat mendukung sterol nabati sebagai bahan makanan sehat yang perlu dikonsumsi dalam diet sehari-hari. Namun masih perlu dilakukan penelitian lebih mendalam tentang manfaat sterol nabati. Abstract

American Journal of Clinical Nutrition October 2006, Vol. 84, No. 4, 756-761. Reduced-calorie orange juice beverage with plant sterols lowers C-reactive protein concentrations and improves the lipid profile in human volunteers. Sridevi Devaraj, Bryce C Autret and Ishwarlal Jialal. Background: Dietary plant sterols effectively reduce LDL cholesterol when incorporated into fat matrices. We showed previously that supplementation with orange juice containing plant sterols (2 g/d) significantly reduced LDL cholesterol. Inflammation is pivotal in atherosclerosis. High-sensitivity C-reactive protein (hs-CRP), the prototypic marker of inflammation, is a cardiovascular disease risk marker; however, there is a paucity of data on the effect of plant sterols on CRP concentrations.

Objective: The aim of this study was to examine whether plant sterols affect CRP concentrations and the lipoprotein profile when incorporated into a reduced-calorie (50 calories/240 mL) orange juice beverage.

Design: Seventy-two healthy subjects were randomly assigned to receive a reduced-calorie orange juice beverage either without (Placebo Bev) or with (1 g/240 mL; Sterol Bev) plant sterols twice a day with meals for 8 wk. Fasting blood was obtained at baseline and after 8 wk of Placebo Bev or Sterol Bev supplementation.

Results: Sterol Bev supplementation significantly reduced total cholesterol (5%; P < 0.01) and LDL cholesterol (9.4%; P < 0.001) compared with both baseline and Placebo Bev (P < 0.05). HDL cholesterol increased significantly with Sterol Bev (P < 0.02). No significant changes in triacylglycerol, glucose, or liver function tests were observed with Sterol Bev. Sterol Bev supplementation resulted in no significant change in vitamin E and carotenoid concentrations. Sterol Bev supplementation resulted in a significant reduction of CRP concentrations compared with baseline and Placebo Bev (median reduction: 12%; P < 0.005).

Conclusion: Supplementation with a reduced-calorie orange juice beverage containing plant sterols is effective in reducing CRP and LDL cholesterol and could be incorporated into the dietary portion of therapeutic lifestyle changes.

Thursday, October 05, 2006

Multivitamin dan Mineral: Dapatkah Mencegah Kanker dan Penyakit Kronik?

Suplemen multivitamin dan mineral sekarang banyak dikonsumsi masyarakat. Seberapa efektif untuk mencegah kanker dan penyakit kronik? Amankah dikonsumsi? Penelitian di bawah ini membedah 12 artikel studi efikasi dan 8 studi keamanan.

Hasil penelitian di Cina pada masyarakat dengan status gizi buruk, suplementasi ß-carotene, tocopherol, dan selenium, mengurangi angka insiden kanker lambung dan mortalitas kanker lain2 sebesar 13-21%. Hasil penelitian di Perancis, suplementasi vitamin C, vitamin E, ß-carotene, selenium, dan zinc mengurangi kejadian kanker sebesar 31% untuk laki2, tapi tidak bermakna untuk wanita. Suplementasi multivitamin dan mineral tidak bermakna untuk penyakit kardiovaskuler atau katarak. Suplementasi ß-carotene, selenium, -tocopherol, retinol, and zinc mengurangi mortalitas stroke sebesar 29% (penelitian Linxian). Suplementasi zinc dan anti-oksidan dapat memperlambat progresi AMD.

Efek samping pemberian multivitamin dan mineral tidak terbukti.

Berdasarkan bukti2 tersebut efektivitas suplementasi kombinasi multivitamin dan mineral untuk mencegah kanker dan penyakit kronik kurang kuat.

Abstract

The Efficacy and Safety of Multivitamin and Mineral Supplement Use To Prevent Cancer and Chronic Disease in Adults: A Systematic Review for a National Institutes of Health State-of-the-Science Conference

Ann Intern Med 5 September 2006. Volume 145 Issue 5, 372-385. © 2006 American College of Physicians – American Society of Internal Medicine

Han-Yao Huang, PhD, MPH; Benjamin Caballero, MD, PhD; Stephanie Chang, MD; Anthony J. Alberg, PhD, MPH; Richard D. Semba, MD, MPH; Christine R. Schneyer, MD; Renee F. Wilson, MSc; Ting-Yuan Cheng, MSc; Jason Vassy, MPH; Gregory Prokopowicz, MD, MPH; George J. Barnes, II, BA; and Eric B. Bass, MD, MPH.

Background: Multivitamin and mineral supplements are the most commonly used dietary supplements in the United States. Purpose: To synthesize studies on the efficacy and safety of multivitamin/mineral supplement use in primary prevention of cancer and chronic disease in the general population. Data Sources: English-language literature search of the MEDLINE, EMBASE, and Cochrane databases through February 2006 and hand-searching of pertinent journals and articles. Study Selection: Randomized, controlled trials in adults were reviewed to assess efficacy, and randomized, controlled trials and observational studies in adults or children were reviewed to assess safety. Data Extraction: Paired reviewers extracted data and independently assessed study quality. Data Synthesis: 12 articles from 5 randomized, controlled trials that assessed efficacy and 8 articles from 4 randomized, controlled trials and 3 case reports on adverse effects were identified. Study quality was rated fair for the studies on cancer, cardiovascular disease, cataracts, or age-related macular degeneration and poor for the studies on hypertension. In a poorly nourished Chinese population, combined supplementation with ß-carotene, -tocopherol, and selenium reduced the incidence of and mortality rate from gastric cancer and the overall mortality rate from cancer by 13% to 21%. In a French trial, combined supplementation with vitamin C, vitamin E, ß-carotene, selenium, and zinc reduced the rate of cancer by 31% in men but not in women. Multivitamin and mineral supplements had no significant effect on cardiovascular disease or cataracts, except that combined ß-carotene, selenium, -tocopherol, retinol, and zinc supplementation reduced the mortality rate from stroke by 29% in the Linxian study and that a combination of 7 vitamins and minerals stabilized visual acuity loss in a small trial. Combined zinc and antioxidants slowed the progression of advanced age-related macular degeneration in high-risk persons. No consistent adverse effects of multivitamin and mineral supplements were evident. Limitations: Only randomized, controlled trials were considered for efficacy assessment. Special nutritional needs, such as use of folic acid by pregnant women to prevent birth defects, were not addressed. Findings may not apply to use of commercial multivitamin supplements by the general U.S. population. Conclusions: Evidence is insufficient to prove the presence or absence of benefits from use of multivitamin and mineral supplements to prevent cancer and chronic disease.

Wednesday, October 04, 2006

Distribusi lemak tubuh dan risiko terjadinya diabetes tipe 2

Penelitian ini bertujuan untuk mengetahui indikator apa (indeks massa tubuh, lingkar pinggang dan rasio lingkar pinggang lingkar panggul) yang paling relevan sebagai prediktor diabetes tipe 2 untuk pria dan wanita.

Subyek penelitian dari MONICA Augsburg sebanyak 3.055 pria dan 2.957 wanita, berusia 35-74 tahun, yang tidak menderita diabetes, difollow-up selama lebih dari 9 tahun.

Ternyata baik lemak tubuh maupun lemak perut berhubungan dengan diabetes tipe 2. Maka untuk prediksi diabetes tipe 2 baik pada pria maupun wanita yang terbaik adalah melakukan pengukuran indeks massa tubuh dan lingkar pinggang.

Abstract

Body fat distribution and risk of type 2 diabetes in the general population: are there differences between men and women? The MONICA/KORA Augsburg Cohort Study

Christa Meisinger, Angela Döring, Barbara Thorand, Margit Heier and Hannelore Löwel American Journal of Clinical Nutrition, Vol. 84, No. 3, 483-489, September 2006 © 2006

Background: It remains controversial whether body mass index (BMI), waist circumference (WC), or waist-hip ratio (WHR) is a better risk predictor of type 2 diabetes.

Objective: The objective was to examine the sex-specific relevance of WC, WHR, and BMI to the development of type 2 diabetes.

Design: The prospective population-based cohort study was based on 3055 men and 2957 women aged 35-74 y who participated in the second (1989-1990) or third (1994-1995) MONICA (Monitoring Trends and Determinants on Cardiovascular Diseases) Augsburg survey. The subjects were free of diabetes at baseline. Hazard ratios (HRs) were estimated from Cox proportional hazards models.

Results: During a mean follow-up of 9.2 y, 243 cases of incident type 2 diabetes occurred in men and 158 occurred in women. Multivariable-adjusted HRs across quartiles of BMI were 1.0, 1.37, 2.08, and 4.15 in men and 1.0, 3.77, 4.95, and 10.58 in women; those of WC were 1.0, 1.15, 1.57, and 3.40 in men and 1.0, 3.21, 3.98, and 10.70 in women; those of WHR were 1.0, 1.14, 1.80, and 2.84 in men and 1.0, 0.82, 2.06, and 3.51 in women. In joint analyses, the highest risk was observed in men and women with a high BMI in combination with a high WC and a high WHR.

Conclusions: Both overall and abdominal adiposity were strongly related to the development of type 2 diabetes. Because there was an additive effect of overall and abdominal obesity on risk prediction, WC should be measured in addition to BMI to assess the risk of type 2 diabetes in both sexes.

Rasio lingkar pinggang-panggul menggambarkan risiko kematian

Penelitian ini bertujuan menilai hubungan antara indeks massa tubuh, lingkar pinggang, dan rasio lingkar pinggang-lingkar panggul terhadap risiko kematian.

Subyek penelitian sebanyak 14.833 orang manula (75 th) dan difollow-up selama hampir 6 tahun.

Kesimpulan penelitian menunjukkan bahwa rasio lingkar pinggang-lingkar panggul berhubungan dengan risiko kematian pada pria dan wanita. Sedangkan indeks massa tubuh dan lingkar pinggang tidak signifikan. Hasil ini mengingatkan pentingnya pengukuran lingkar pinggang dan lingkar panggul.

Abstract

Weight, shape, and mortality risk in older persons: elevated waist-hip ratio, not high body mass index, is associated with a greater risk of death

Gill M Price, Ricardo Uauy, Elizabeth Breeze, Christopher J Bulpitt and Astrid E Fletcher

American Journal of Clinical Nutrition, Vol. 84, No. 2, 449-460, August 2006 © 2006

Background: Guidelines for optimal weight in older persons are limited by uncertainty about the ideal body mass index (BMI) or the usefulness of alternative anthropometric measures. Objective: We investigated the association of BMI (in kg/m2), waist circumference, and waist-hip ratio (WHR) with mortality and cause-specific mortality. Design: Subjects aged 75 y (n = 14 833) from 53 family practices in the United Kingdom underwent a health assessment that included measurement of BMI and waist and hip circumferences; they also were followed up for mortality. Results: During a median follow-up of 5.9 y, 6649 subjects died (46% of circulatory causes). In nonsmoking men and women (90% of the cohort), compared with the lowest quintile of BMI (<23 in men and <22.3 in women), adjusted hazard ratios (HRs) for mortality were <1 for all other quintiles of BMI (P for trend = 0.0003 and 0.0001 in men and women, respectively). Increasing WHR was associated with increasing HRs in men and women (P for trend = 0.008 and 0.0002, respectively). BMI was not associated with circulatory mortality in men (P for trend = 0.667) and was negatively associated in women (P for trend = 0.004). WHR was positively related to circulatory mortality in both men and women (P for trend = 0.001 and 0.005, respectively). Waist circumference was not associated with all-cause or circulatory mortality.

Conclusions: Current guidelines for BMI-based risk categories overestimate risks due to excess weight in persons aged 75 y. Increased mortality risk is more clearly indicated for relative abdominal obesity as measured by high WHR.

Tuesday, October 03, 2006

What Should We Eat?

Untuk menjaga kesehatan diet seperti apakah yang harus dikonsumsi? Suatu penelitian membuktikan bahwa sebaiknya kita mengkonsumsi diet yang kaya buah dan sayuran, kacang2an, biji2an, lemak tak jenuh dan ikan, serta menghindari lemak jenuh, garam dan daging merah. Semuanya disusun dalam menu sehari2 yang cukup kalori, tidak perlu berlebihan.

Southern Medical Journal. July 2006, Volume 99, Issue 7. © 2006 Southern Medical Association. What Should We Eat? Evidence from Observational Studies, Stephen M. Adams, MD; John B. Standridge, MD.

Abstract: Observational studies provide a wealth of important correlations between diet and disease. There is a clear pattern of dietary habits that is associated with reduced rates of a multitude of common illnesses, including heart attack, cancer, stroke, diabetes, and hypertension. In some cases, interventional studies have proven the benefits of dietary change; in others, there is insufficient evidence to prove causation. Based on the existing evidence, the optimal diet should emphasize fruits and vegetables, nuts, unsaturated oils, whole grains, and fish, while minimizing saturated fats (especially trans fats), sodium, and red meats. Its overall calorie content should be low enough to maintain a healthy weight.

Thursday, August 24, 2006

Effects of a Mediterranean-Style Diet on Cardiovascular Risk Factors

Ann Intern Med 4 July 2006, Volume 145 Issue 1, 1-11. © 2006 American Medical Association. All rights reserved. Effects of a Mediterranean-Style Diet on Cardiovascular Risk Factors - A Randomized Trial, Ramon Estruch, MD, PhD; Miguel Ángel Martínez-González, MD, PhD; Dolores Corella, PhD; Jordi Salas-Salvadó, MD, PhD; Valentina Ruiz-Gutiérrez, PhD; María Isabel Covas, PhD; Miguel Fiol, MD, PhD; Enrique Gómez-Gracia, MD, PhD; Mari Carmen López-Sabater, PhD; Ernest Vinyoles, MD, PhD; Fernando Arós, MD, PhD; Manuel Conde, MD, PhD; Carlos Lahoz, MD, PhD; José Lapetra, MD, PhD; Guillermo Sáez, MD, PhD; Emilio Ros, MD, PhD, for the PREDIMED Study Investigators. Correspondence to Ramon Estruch, MD, PhD

Background: The Mediterranean diet has been shown to have beneficial effects on cardiovascular risk factors.

Objective: To compare the short-term effects of 2 Mediterranean diets versus those of a low-fat diet on intermediate markers of cardiovascular risk.

Design: Substudy of a multicenter, randomized, primary prevention trial of cardiovascular disease (Prevención con Dieta Mediterránea [PREDIMED] Study).

Setting: Primary care centers affiliated with 10 teaching hospitals.

Participants: 772 asymptomatic persons 55 to 80 years of age at high cardiovascular risk who were recruited from October 2003 to March 2004.

Interventions: Participants were assigned to a low-fat diet (n = 257) or to 1 of 2 Mediterranean diets. Those allocated to Mediterranean diets received nutritional education and either free virgin olive oil, 1 liter per week (n = 257), or free nuts, 30 g/d (n = 258). The authors evaluated outcome changes at 3 months.

Measurements: Body weight, blood pressure, lipid profile, glucose levels, and inflammatory molecules.

Results: The completion rate was 99.6%. Compared with the low-fat diet, the 2 Mediterranean diets produced beneficial changes in most outcomes. Compared with the low-fat diet, the mean changes in the Mediterranean diet with olive oil group and the Mediterranean diet with nuts group were -0.39 mmol/L (95% CI, -0.70 to - 0.07 mmol/L) and - 0.30 mmol/L (CI, -0.58 to - 0.01 mmol/L), respectively, for plasma glucose levels; -5.9 mm Hg (CI, -8.7 to -3.1 mm Hg) and - 7.1 mm Hg (CI, -10.0 to -4.1 mm Hg), respectively, for systolic blood pressure; and -0.38 (CI, -0.55 to - 0.22) and - 0.26 (CI, -0.42 to -0.10), respectively, for the cholesterol-high-density lipoprotein cholesterol ratio. The Mediterranean diet with olive oil reduced C-reactive protein levels by 0.54 mg/L (CI, 1.04 to 0.03 mg/L) compared with the low-fat diet.

Limitations: This short-term study did not focus on clinical outcomes. Nutritional education about low-fat diet was less intense than education about Mediterranean diets.

Conclusion: Compared with a low-fat diet, Mediterranean diets supplemented with olive oil or nuts have beneficial effects on cardiovascular risk factors.

Pengaruh diet Mediterrania terhadap Faktor Risiko Kardiovaskuler

Telah diketahui bahwa diet Mediterrania dapat memperbaiki faktor risiko penyakit kardiovaskuler (PKV). Para ahli di Spanyol hendak membandingkan pengaruh diet Mediterrania (tinggi lemak golongan MUFA) dibanding diet rendah lemak terhadap faktor risiko PKV.

Penelitian berlangsung dari 2003 sampai 2004, diambil dari 10 sentra kesehatan dan dilakukan randomisasi, melibatkan 772 pasien asimptomatik risiko tinggi PKV, berusia 55-80 tahun. Pasien di-randomized menjadi kelompok diet rendah lemak (n=257) atau salah satu dari dua jenis diet Mediterrania, yaitu kelompok yang mendapat 1 liter perminggu virgin olive oil (n=257) atau 30g perhari kacang (n=258). Evaluasi dilakukan tiap 3 bulan terhadap berat badan, tekanan darah, profil lipid, kadar gula darah, dan penanda inflamasi.

Ternyata dibanding diet rendah lemak, kedua diet Mediterrania yang tinggi lemak MUFA lebih unggul dalam hal menurunkan kadar gula darah, menurunkan tekanan sistolik, menurunkan rasio kolesterol terhadap HDL. Diet Mediterrania dengan olive oil menurunkan kadar C-reactive protein (CRP adalah penanda inflamasi) dibanding diet rendah lemak.

Kesimpulan dari penelitian ini adalah diet Mediterrania yang tinggi lemak MUFA (sumber MUFA dari olive oil atau kacang) lebih unggul dalam memperbaiki faktor risiko PKV dibanding diet rendah lemak.

Wednesday, August 23, 2006

Adult Obesity and Number of Years Lived with and without Cardiovascular Disease

M. Carolina Pardo Silva*,, Chris De Laet*, Wilma J. Nusselder*, Abdulah A. Mamun and Anna Peeters*, * Department of Public Health and Department of Epidemiology and Biostatistics, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands; School of Population Health, University of Queensland, Queensland, Australia; and Department of Epidemiology and Public Health, Monash University, Victoria, Australia.

Abstract

Objective: To determine the differences in number of years lived free of cardiovascular disease (CVD) and number of years lived with CVD between men and women who were obese, pre-obese, or normal weight at 45 years of age. Research Methods and Procedures: We constructed multistate life tables for CVD, myocardial infarction, and stroke, using data from 2551 enrollees (1130 men) in the Framingham Heart Study who were 45 years of age. Results: Obesity and pre-obesity were associated with fewer number of years free of CVD, myocardial infarction, and stroke and an increase in the number of years lived with these diseases. Forty-five-year-old obese men with no CVD survived 6.0 years [95% confidence interval (CI), 4.1; 8.1] fewer than their normal weight counterparts, whereas, for women, the difference between obese and normal weight subjects was 8.4 years (95% CI: 6.2; 10.8). Obese men and women lived with CVD 2.7 (95% CI: 1.0; 4.4) and 1.4 years (95% CI: -0.3; 3.2) longer, respectively, than normal weight individuals. Discussion: In addition to reducing life expectancy, obesity before middle age is associated with a reduction in the number of years lived free of CVD and an increase in the number of years lived with CVD. Such information is paramount for preventive and therapeutic decision-making by individuals and practitioners alike.

Para peneliti dari Belanda dan Australia ingin mengetahui masa depan orang obesitas, pra-obesitas dan orang normal mulai usia 45 tahun, terhadap terjadinya penyakit kardiovaskuler (PKV), infark miokard (IM) dan strok. Data diambil dari Framingham Heart Study, jumlah sampel 2551 orang, 1130 laki2 dan sisanya wanita.

Ternyata keadaan obesitas dan pra-obesitas menyebabkan lebih sedikit tahun kehidupan tanpa PKV, IM dan strok. Dengan kata lain obesitas dan pra-obesitas menyebabkan seseorang lebih lama hidup mengidap ketiga penyakit tersebut. Laki2 usia 45 tahun dengan obesitas 6 tahun lebih awal terkena PKV dibanding laki2 normal usia yang sama. Untuk wanita perbedaan mencapai 8,4 tahun. Sedangkan laki2 dan wanita obesitas menderita PKV masing2 2,7 tahun dan 1,4 tahun lebih lama dibanding orang normal.

Kesimpulannya obesitas pada usia pertengahan akan memperpendek waktu hidup bebas PKV dan memperpanjang penderitaan PKV. Sehingga pencegahan dan terapi obesitas pada usia pertengahan adalah sangat penting.

Thursday, July 27, 2006

Kopi (decaffeinated) menurunkan risiko diabetes mellitus tipe 2

Minum kopi diduga dapat menurunkan risiko terkena diabetes mellitus karena kopi mengandung berbagai mineral, fitokemikal dan anti-oksidan, sedangkan peran kafein belum jelas. Maka perlu dilakukan penelitian yang membandingkan antara kopi mengandung kafein dan kopi tanpa kafein (decaffeinated) terhadap risiko timbulnya penyakit diabetes mellitus tipe 2.

Penelitian prospektif yang disebut Iowa Women's Health Study berlangsung dari tahun 1986 sampai1997, melibatkan 28.812 wanita pasca menopaus sehat, tidak menderita diabetes dan penyakit kardiovaskuler.

Asupan kopi digolongkan sebagai 0, kurang dari 1, 1 sampai 3, 4 sampai 5, lebih dari 6 cangkir per hari. Dalam follow up selama 11 tahun, insiden diabetes mellitus adalah 1.418 kasus.

Wanita yang minum >6 cangkir kopi per hari mempunyai relative risk 22% lebih rendah dibanding wanita yang minum 0 cangkir perhari (RR=0,78, P for trend=0,06).

Jika dipilah antara kopi biasa dan kopi tanpa kafein maka menjadi lebih jelas. Pada kopi tanpa kafein RR=0,67 ; p=0,006. Sedangkan pada kopi biasa RR=0,79 ; P for trend=0,90.

Kesimpulan penelitian ini bahwa asupan kopi terutama kopi tanpa kafein (decaffeinated) berhubungan terbalik dengan risiko diabetes mellitus tipe 2 pada wanita pasca menopaus.

Arch Intern Med. 2006;166:1311-1316. June 26, 2006. © 2006 American College of Physicians – American Society of Internal Medicine Coffee Consumption and Risk of Type 2 Diabetes Mellitus - An 11-Year Prospective Study of 28 812 Postmenopausal Women, Mark A. Pereira, PhD; Emily D. Parker, MPH; Aaron R. Folsom, MD

Thursday, July 20, 2006

Diabetes dan Kehamilan

Diabetes pada ibu hamil dibedakan 2 yaitu 1)sudah menderita diabetes sebelum hamil dan 2)diabetes timbul akibat kehamilan (gestational diabetes mellitus disingkat GDM).

Penderita disarankan untuk melakukan : * Kontrol lebih ketat ke dokter ObsGin, Internis dan Gizi. * Pemeriksaan kadar gula darah, dengan target gula darah puasa <105 mg/dL ; gula darah 2 jam post-prandial <130 mg/dL. * Penimbangan untuk monitoring peningkatan berat badan. * Olah raga ringan selama tidak ada kontra-indikasi. * Restriksi energi dengan menjalankan diet terutama bagi ibu yang obesitas (IMT>30). * Pemberian ASI setelah melahirkan karena akan memperbaiki kontrol gula darahnya.

Manajemen diet 1. Kebutuhan energi sebesar 20-30 Kal/kgBB perhari disesuaikan dengan kelebihan berat badan. 2. Bila perlu dilakukan restriksi karbohidrat +40% energi total. Dianjurkan mengkonsumsi bahan makanan yang indeks glikemik-nya rendah. 3. Asupan protein 0,75 g/kgBB perhari ditambah 10 g perhari bila fungsi ginjal normal. 4. Restriksi asam lemak jenuh <10% energi total, diganti dengan MUFA dan PUFA. 5. Restriksi kolesterol <300 mg perhari. 6. Asupan serat dianjurkan 25-30 g perhari dari bahan makanan tinggi serat. 7. Asupan mikronutrien vitamin dan mineral. Kalsium dianjurkan 1200 mg perhari. 8. Pemanis buatan (aspartame, sucralose, acesulfame K, saccharin) boleh dipergunakan secukupnya. 9. Tidak dianjurkan mengkonsumsi alkohol karena dapat menyebabkan hipoglikemia. 10. Pengaturan dosis dan waktu pemberian antara makan utama dan selingan untuk mencegah hiperglikemia ataupun hipoglikemia.

www.kliniknutrisi.com

Age-related macular degeneration (AMD)

AMD (age-related macular degeneration) adalah gangguan pengelihatan akibat proses degenerasi pada retina. AMD bersifat menetap (irreversible) dan merupakan penyebab kebutaan utama di negara2 maju.

Hasil penelitian epidemiologi, pada hewan dan laboratorium menunjukkan bahwa faktor nutrisi berperan dalam mencegah AMD melalui mekanisme anti-oksidan. Retina merupakan jaringan yang peka terhadap kerusakan oksidatif karena membran retina terdiri dari asam lemak tak jenuh jamak (polyunsaturated fatty acids = PUFA) yang akan mengalami reaksi peroksidasi lipid.

Data epidemiologis membuktikan bahwa asupan buah dan sayuran dapat mencegah AMD. Penelitian di Belanda menyimpulkan bahwa peningkatan asupan vitamin E dan Zinc sebesar 1 standar deviasi dapat mengurangi risiko AMD sebanyak 8%. Orang yang mengkonsumsi beta karoten, vitamin C, E dan Zinc di atas rata2, dapat mengurangi risiko AMD sebesar 15%.

Lutein dan zeaxanthin adalah karotenoid yang terdapat dalam sayuran berwarna hijau gelap dan kuning. Lutein dan zeaxanthin banyak terdapat pada mata (terutama pada bagian sentral retina) dan merupakan zat penting dalam proses pengelihatan. Keduanya bersama Likopen, melindungi makula terhadap kerusakan foto-oksidatif.

Zinc dan Selenium adalah mineral yang berperan sebagai anti-oksidan dan dalam proses metabolisme di retina. Perannya dalam mencegah AMD belum jelas. Dalam penelitian RCT selama >6 tahun melibatkan >3500 pasien berusia >55 tahun progresi AMD dapat diperlambat sampai 30% dengan pemberian kombinasi anti-oksidan mengandung Zinc, vitamin C, E dan karoten (AREDS trial).

Retina merupakan jaringan yang kaya lipoprotein (lemak dan protein). Beberapa bukti menunjukkan bahwa asam lemak jenuh (saturated fat) - yang juga berperan dalam terjadinya proses aterosklerosis - dapat meningkatkan risiko AMD. Sedangkan PUFA omega-3 melindungi terhadap AMD.

Penelitian di Italia menggunakan kombinasi anti-oksidan mengandung L-carnitine, PUFA omega:3 (EPA dan DHA), serta coenzyme Q10 menunjukkan hasil positif. Penelitian di AS menggunakan vitamin A dosis tinggi juga menunjukkan hasil yang positif. Pengaruh anti-oksidan lain terhadap AMD misalnya kopi, wine, homosistein, riboflavin, masih dalam penelitian.

Secara keseluruhan diyakini bahwa nutrien - khususnya anti-oksidan - dapat mencegah dan menghambat progresi AMD. Untuk mencapai efek anti-oksidan yang optimal perlu kombinasi nutrien. Namun apakah nutrisi dapat digunakan untuk terapi AMD memerlukan penelitian lebih jauh. Perlu diingat bahwa tidak ada satu nutrien pun yang mempunyai pengaruh kuat sebesar pengaruh buruk akibat merokok. Artinya pengaruh buruk rokok akan mengalahkan nutrien anti-oksidan manapun.

Untuk pencegahan AMD www.kliniknutrisi.com menganjurkan banyak konsumsi buah dan sayuran serta berhenti merokok.

Wednesday, July 05, 2006

Diet rendah karbohidrat

Am Fam Physician 2006;73:1942-8, 1951. June 1, 2006. © 2006 American Academy of Family Physicians. Low-Carbohydrate Diets. Allen R. Last, M.D., M.P.H. and Stephen A. Wilson, M.D., M.P.H.

Masyarakat USA membelanjakan 33 milyar dollar setiap tahun untuk produk dan jasa penurunan berat badan. Salah satu pendekatan adalah diet rendah karbohidrat (DRK). Diet rendah karbohidrat berarti diet tinggi protein dan lemak serta rendah serat. Amankah DRK ini? Data pendukung dari penelitian jangka panjang masih kurang. Namun penelitian jangka pendek yang membandingkan DRK dengan diet tinggi karbohidrat rendah lemak mendapatkan bahwa penganut DRK mempunyai kadar trigliserida lebih rendah, kadar kolesterol HDL (good cholesterol) lebih tinggi, kadar kolesterol LDL (bad cholesterol) sama, dan kadar A1C lebih rendah. DRK juga menurunkan berat badan lebih besar dibandingkan diet rendah lemak sampai 6 bulan pertama, namun setelah 1 tahun tidak ada beda bermakna antara kedua diet. Hal ini disebabkan penurunan berat badan tergantung jumlah kalori yang dikonsumsi, dan bukan dipengaruhi oleh komposisi nutrien dalam makanan. Penganut DRK lebih patuh dan jarang terjadi drop out, kemungkinan disebabkan kadar protein tinggi dalam makanan memberikan rasa kenyang lebih lama.

www.kliniknutrisi.com menyimpulkan DRK cukup aman dalam menurunkan berat badan dan merupakan alternatif pendekatan tradisional dengan diet rendah lemak. Namun diperlukan penelitian lebih lanjut untuk mengetahui keamanan dan efektifitas jangka panjangnya.

Tuesday, June 20, 2006

Kopi mengurangi risiko kematian akibat penyakit kardiovaskuler

American Journal of Clinical Nutrition. Vol. 83, No. 5, 1039-1046, May 2006. 2006 American Society for Nutrition Consumption of coffee is associated with reduced risk of death attributed to inflammatory and cardiovascular diseases in the Iowa Women's Health Study, Lene Frost Andersen, David R Jacobs, Jr, Monica H Carlsen and Rune Blomhoff.

Kopi merupakan sumber utama anti-oksidan dalam makanan sehari-hari, maka perlu diteliti hubungan konsumsi kopi dengan risiko kematian akibat penyakit kardiovaskuler, keganasan, dan penyakit2 yang diawali dengan proses inflamasi dan stres oksidasi. Penelitian dilakukan selama 15 tahun di Iowa (USA) terhadap 27.312 orang wanita sehat pasca menopaus berusia 55-69 tahun (410.235 person-years of follow-up).

Hasil penelitian rasio hazard kematian adalah 0,76 (95% CI: 0.64, 0.91) untuk konsumsi 1-3 cangkir perhari, 0,81 (95% CI: 0.66, 0.99) untuk konsumsi 4-5 cangkir perhari, 0.87 (95% CI: 0.69, 1.09) untuk konsumsi 6 cangkir perhari. Rasio hazard untuk kematian akibat penyakit inflamasi lainnya adalah 0.72 (95% CI: 0.55, 0.93) untuk konsumsi 1-3 cangkir perhari, 0.67 (95% CI: 0.50, 0.90) untuk konsumsi 4-5 cangkir perhari, 0.68 (95% CI: 0.49, 0.94) untuk konsumsi 6 cangkir perhari.

Demikian disimpulkan bahwa konsumsi anti-oksidan (salah satu sumbernya adalah kopi) dapat menghambat proses inflamasi sehingga dapat menurunkan risiko kematian akibat penyakit kardiovaskuler dan penyakit inflamasi lainnya.

Thursday, June 01, 2006

Yogurt dan keju rendah lemak yang diperkaya sterol nabati dapat menurunkan kadar kolesterol

European Journal of Clinical Nutrition May 2006 60, 633-642. doi:10.1038/sj.ejcn.1602362. © 2006 Nature Publishing Group Safety aspects and cholesterol-lowering efficacy of low fat dairy products containing plant sterols, R Korpela, J Tuomilehto, P Högström, L Seppo, V Piironen, P Salo-Väänänen, J Toivo, C Lamberg-Allardt, M Kärkkäinen, T Outila, J Sundvall, S Vilkkilä and M J Tikkanen.

Untuk mengetahui manfaat sterol nabati menurunkan kolesterol peneliti di Finlandia melakukan penelitian paralel double blind di tiga lokasi melibatkan 64 pasien hiperkolesterolemia. Dilakukan randomisasi menjadi 2 kelompok, yang mendapatkan campuran sterol nabati dalam produk susu (dairy) rendah lemak dan kelompok kontrol. Subyek mengkonsumsi produk selama 6 minggu. Kadar sterol nabati 2 g/hari.

Kadar kolesterol total turun 6,5% pada kelompok sterol sedangkan kelompok kontrol tidak berubah (p<0,0005). Kadar kolesterol LDL turun 10,4% pada kelompok sterol sedangkan kelompok kontrol turun 0,6% (p<0,00005). Kadar kolesterol HDL dan trigliserida tidak berubah signifikan selama penelitian. Rasio HDL/LDL naik 16,1% pada kelompok sterol dan naik 4,3% pada kelompok kontrol (p=0,0001). Kadar vitamin larut lemak tidak berubah signifikan. Efek hipokolesterolemik sterol nabati tidak dipengaruhi fenotip apolipoprotein E.

Kesimpulan: yogurt, keju rendah lemak yang diperkaya dengan sterol nabati dapat menurunkan kadar kolesterol pada pasien hiperkolesterolemia. Untuk penderita hiperkolesterolemia yang ingin mengkonsumsi produk susu (dairy) dianjurkan memilih yang rendah lemak dan mengandung sterol nabati.

Thursday, May 04, 2006

Suplementasi asam folat, vitamin B6 dan B12 tidak mengurangi risi ko kematian kardiovaskuler

N Eng J Med. Volume 354:1567-1577 April 13, 2006 Number 15. © 2006 Massachusetts Medical Society. All rights reserved. Homocysteine Lowering with Folic Acid and B Vitamins in Vascular Disease - The Heart Outcomes Prevention Evaluation (HOPE) 2 Investigators.

Dalam studi observasi, kadar homosistein rendah berhubungan dengan penurunan penyakit jantung koroner (PJK) dan stroke. Diketahui bahwa asam folat, vitamin B6 dan B12 dapat menurunkan kadar homosistein. Para ahli di Kanada meneliti apakah suplementasi dapat mengurangi kejadian kardiovaskuler pada pasien yang sudah menderita penyakit vaskuler. Sebanyak 5.522 pasien berusia >55 tahun yang menderita penyakit vaskuler atau diabetes secara acak (random) diberi terapi kombinasi 2.5 mg asam folat, 50 mg vitamin B6, dan 1 mg vitamin B12 atau plasebo, selama 5 tahun.

Hasilnya adalah penurunan kadar homosistein plasma sebesar 2,4 µmol per liter (0.3 mg per liter) pada kelompok terapi, dan peningkatan kadar homosistein plasma sebesar 0.8 µmol per liter (0.1 mg per liter) pada kelompok plasebo. Kematian kardiovaskuler (akibat dari penyakit kardiovaskuler, infark miokard dan stroke) terjadi pada 18,8% kelompok terapi dan 19,8% kelompok plasebo (RR=0,95; P=0,41). Relative risk risiko kematian kardiovaskuler pada kelompok terapi adalah 0,96 dibanding kelompok plasebo, sedangkan untuk miokard infark adalah 0,98. Namun relative risk risiko kematian akibat stroke pada kelompok terapi adalah 0,75 dibanding kelompok plasebo.

Kesimpulan suplementasi kombinasi asam folat, vitamin B6 dan B12 dapat menurunkan kadar homosistein, namun tidak signifikan mengurangi risiko kematian kardiovaskuler pada penderita penyakit vaskuler.

Wednesday, May 03, 2006

Kopi tidak menyebabkan penyakit jantung koroner (PJK)

Circulation 2006 (doi:10.1161/CIRCULATIONAHA.105.598664) published online April 24, 2006. © 2006 by the American Heart Association Coffee Consumption and Coronary Heart Disease in Men and Women. A Prospective Cohort Study, Esther Lopez-Garcia DrPH, Rob M. van Dam PhD, Walter C. Willett MD, DrPH, Eric B. Rimm ScD, JoAnn E. Manson MD, DrPH, Meir J. Stampfer MD, DrPH, Kathryn M. Rexrode MD, MPH, and Frank B. Hu MD, PhD.

Untuk mengetahui hubungan kebiasaan minum kopi dan risiko PJK, para peneliti di Boston Amerika Serikat, melakukan studi kohort prospektif terhadap 44.005 pria dan 84.488 wanita sehat. Jumlah konsumsi kopi dinilai kemudian dilakukan follow up selama 14 tahun untuk pria dan 20 tahun untuk wanita sampai tahun 2000. Pada pria terjadi 2.173 kasus PJK (1.449 nonfatal miokard infark dan 724 fatal). Pada wanita terjadi 2.254 kasus (1.561 nonfatal miokard infark dan 693 fatal).

Berdasarkan jumlah konsumsi kopi, responden digolongkan sebagai berikut: <1 cangkir/bulan, 1cangkir/bulan sampai 4 cangkir/minggu, 5-7 cangkir per minggu, 2-3 cangkir per hari, 4-5 cangkir per hari dan >6 cangkir per hari. Pada pria setelah adjustment terhadap usia, status perokok dan faktor risiko PJK lain, relative risk (RR) untuk PJK adalah 1.0, 1.04, 1.02, 0.97, 1.07 and 0.72 (P for trend=0.41); sedangkan pada wanita RR untuk PJK adalah 1.0, 0.97, 1.02, 0.84, 0.99 and 0.87 (P for trend=0.08). Setelah stratifikasi status perokok, konsumsi alkohol, riwayat diabetes melitus tipe 2 dan indeks massa tubuh hasilnya sama saja.

Kesimpulan setelah diikuti selama 20 tahun tidak diperoleh bukti bahwa konsumsi kopi meningkatkan risiko PJK.

Wednesday, April 26, 2006

Teh hijau, kopi dan cafein menurunkan risiko diabetes tipe 2

Ann Intern Med. 18 April 2006, Volume 144 Issue 8, Pages 554-562. © 2006 American College of Physicians - American Society of Internal Medicine. The Relationship between Green Tea and Total Caffeine Intake and Risk for Self-Reported Type 2 Diabetes among Japanese Adults, Hiroyasu Iso, MD; Chigusa Date, PhD; Kenji Wakai, MD; Mitsuru Fukui, PhD; Akiko Tamakoshi, MD, and the JACC Study Group.

Para peneliti di Jepang meneliti hubungan konsumsi kopi, teh hijau, teh hitam dan teh oolong terhadap diabetes tipe 2. Desain penelitian kohort retrospektif, dilakukan pada 25 komunitas di Jepang melibatkan 17.413 subyek (6727 pria dan 10.686 wanita) berusia 40-65 tahun, yang tidak punya riwayat diabetes, penyakit kardiovaskuler, atau kanker pada awal penelitian, dan di-follow up selama 5 tahun.

Setelah 5 tahun, terjadi 444 kasus diabetes self reported pada 231 pria dan 213 wanita (5-year event rates, masing-masing 3,4% dan 2,0%). Konsumsi teh hijau dan kopi berhubungan terbalik dengan risiko diabetes. Risiko diabetes untuk orang yang sering minum teh hijau dan kopi (6 cangkir teh hijau perhari dan 3 cangkir kopi perhari) adalah 0,67 dan 0,58, dibanding orang yang minum kurang dari 1 cangkir per minggu. Untuk teh hitam dan teh oolong tidak diperoleh hubungan dengan diabetes. Asupan kafein total dari minuman tersebut menurunkan risiko diabetes sebanyak 33%. Manfaatnya lebih kuat pada wanita dan pada pria yang overweight.

Kesimpulannya konsumsi kafein yang terdapat dalam teh hijau dan kopi dapat menurunkan risiko terjadinya diabetes tipe 2. Nasihat untuk pasien yang berisiko diabetes tipe 2, dianjurkan mengkonsumsi kafein yang berasal dari teh hijau atau kopi.

Saturday, April 22, 2006

Diet Atkins

Seringkali pasien bertanya tentang diet Atkins, tiger diet, diet protein. Diet apakah itu? Bermanfaatkah (atau berbahayakah)? Demikianlah penjelasan saya.
Diet rendah karbohidrat yang telah lama dikenal, kembali dipopulerkan oleh Dr. Atkins dalam 30 tahun terakhir melalui bukunya ‘Dr Atkins New Diet Revolution’. Diet ini menganjurkan pengikutnya untuk menghindari karbohidrat karena karbohidrat dianggap menyebabkan kenaikan kadar gula darah sehingga meningkatkan produksi insulin. Insulin yang berlebihan menyebabkan tubuh menyimpan karbohidrat dalam bentuk lemak. Namun produksi insulin sebenarnya tidak disebabkan oleh konsumsi karbohidrat saja, tapi oleh konsumsi energi (dalam bentuk makanan dan minuman) yang berlebihan. Pada keadaan berat badan lebih (overweight) terjadi peningkatan kadar insulin. Karena diet sangat rendah karbohidrat maka tubuh dapat berada dalam keadaan ketosis (dimana tubuh memecah lemak menjadi keton untuk digunakan sebagai sumber energi pengganti karbohidrat). Dalam diet Atkins fase awal memang akan terjadi ketosis, sehingga terjadi pemecahan lemak tubuh diikuti penurunan berat badan. Tubuh manusia memang punya kemampuan untuk mengalami ketosis dalam keadaan tertentu. Tapi ketosis yang berkepanjangan tidak dianjurkan karena dapat mengganggu kesehatan. Bagaimanakah cara menjalankan diet Atkins ? Diet Atkins menganjurkan konsumsi protein dan lemak namun menghindari karbohidrat. Konsumsi daging, telur, ikan, keju, diperbolehkan bahkan jumlahnya dibebaskan. Sedangkan nasi, roti, mie, kentang, dan sumber karbohidrat lainnya harus dihindari. Pada fase awal akan terjadi penurunan berat badan yang cepat karena terjadi ketosis. Dalam keadaan ketosis tubuh membuang banyak cairan melalui urin. Pandangan dari sudut medis Beberapa penelitian tentang diet Atkins menunjukkan hasil positif pada awalnya, namun dalam jangka panjang terjadi kenaikan berat badan lagi karena diet ini sulit dipatuhi. Namun karena penelitian yang dilakukan hanya melibatkan sedikit subyek, maka diperlukan penelitian yang lebih besar untuk memperoleh kesimpulan yang lebih berbobot. Secara medis menghindari suatu nutrien (dalam hal ini karbohidrat) dapat mengganggu kesehatan. Karbohidrat adalah sumber energi, sehingga menghindari karbohidrat dapat menyebabkan tubuh kurang energi menimbulkan rasa kelelahan, fatigue. Menghindari karbohidrat menyebabkan diet kurang serat sehingga dapat menyebabkan konstipasi dan sebagainya. Diet Atkins menganjurkan penggunaan laksansia untuk mengatasi konstipasi, suatu hal yang sia-sia dan bisa membahayakan kesehatan saluran cerna. Menghindari buah dan sayuran (keduanya adalah karbohidrat) menyebabkan asupan vitamin, mineral dan anti-oksidan alami tidak terpenuhi. Karbohidrat mengandung berbagai zat esensial yang diperlukan untuk menjaga kesehatan tubuh.

Wortel, tomat dan sayuran hijau mencegah serangan asma

Ternyata wortel, tomat dan sayuran hijau juga dapat mencegah serangan asma. Sebuah penelitian yang dilakukan di Perancis membuktikan hal ini.
Thorax 2006;61:209-215 6 March 2006 © 2006 BMJ Publishing Group Ltd & British Thoracic Society. Fruit and vegetable intakes and asthma in the E3N study, I Romieu, R Varraso, V Avene, B Leynaert et al. Untuk mengetahui pengaruh makanan terhadap prevalensi asma pada orang dewasa, di Perancis dilakukan survei terhadap 68.535 perempuan menggunakan food frequency questionnaire yang mencakup 238 item bahan makanan. Sebanyak 2.145 responden adalah penderita asma. Setelah adjustment terhadap usia, IMT, status menopause, status perokok, asupan kalori total, aktivitas fisik, dan pemakaian suplementasi makanan lainnya, disimpulkan bahwa pada kelompok yang lebih banyak makan tomat, wortel dan sayuran berdaun, prevalensi asma-nya lebih rendah. Buah dan sayuran lain tidak berhubungan signifikan terhadap prevalensi asma. Penelitian ini membuktikan bahwa asupan wortel, tomat, dan sayuran hijau setiap hari dapat menurunkan prevalensi asma pada orang dewasa.

Wednesday, April 12, 2006

Vitamin C mencegah common cold

European Journal of Clinical Nutrition (2006) 60, 9–17. January 2006. doi:10.1038/sj.ejcn.1602261. © 2006 Nature Publishing GroupEffect of vitamin C on common cold: randomized controlled trial, S Sasazuki, S Sasaki, Y Tsubono, S Okubo, M Hayashi and S Tsugane. To investigate the relationship between the common cold and vitamin C supplementation, Japanese researchers carried out a double-blind, 5-year randomized controlled trial in a village in Akita prefecture, one of the regions in Japan with the highest mortality from gastric cancer. Participants were those involved in annual screening programs for circulatory diseases conducted under the National Health and Welfare Services Law for the Aged, and diagnosed as having atrophic gastritis. Of the 439 eligible subjects, 144 and 161 were assigned to receive 50 or 500 mg of vitamin C, respectively, after protocol amendment. During the supplementation phase, 61 dropped out, and 244 completed the trial.They found that the total number of common colds (per 1000 person-months) was 21.3 and 17.1 for the low- and high-dose groups, respectively. After adjustment for several factors, the relative risks of suffering from a common cold three or more times during the survey period was 0.34 for the high-dose group. No apparent reduction was seen for the severity and duration of the common cold. Penelitian RCT selama 5 tahun membuktikan bahwa suplementasi vitamin C dapat mengurangi frekuensi common cold, meskipun tidak mempengaruhi durasi dan beratnya penyakit.

Tuesday, April 11, 2006

Antibiotika meningkatkan risiko asma

Chest. 2006;129:610-618. March 2006. © 2006 American College of Chest Physicians. Does Antibiotic Exposure During Infancy Lead to Development of Asthma? A Systematic Review and Metaanalysis, Fawziah Marra, PharmD; Larry Lynd, BSP, PhD; Megan Coombes, MSc; Kathryn Richardson, MSc; Michael Legal, PharmD; J. Mark FitzGerald, MB, MD and Carlo A. Marra, PharmD, PhD. Correspondence to Carlo A. Marra, PharmD, PhD To determine the association between antibiotic exposure in the first year of life and the development of childhood asthma, University of British Columbia researchers carried out a meta-analysis of observational studies retrieved through systematic search of all available electronic data sources. Studies included in the meta-analyses were those with populations exposed to one or more courses of antibiotics during the first year of life, and asthma diagnosis was defined as diagnosis by a physician between the age of 1 to 18 years. Retrospective and prospective studies published in the English-language literature from 1966 to present were included. They found that 8 studies (four prospective and four retrospective) examined the association between exposure to at least one course of antibiotics and development of childhood asthma. The total number of subjects for the analysis comparing exposure to at least one antibiotic to no exposure in the first year of life was 12,082 children and 1,817 asthma cases. In the dose-response analysis, we included data from a total of 27,167 children and 3,392 asthma cases. The pooled odds ratio (OR) for the eight studies was 2.05. The association was significantly stronger in the retrospective studies (OR, 2.82) than the prospective studies (OR, 1.12). Five of the eight studies examined whether the association was related to the number of courses of antibiotics taken in the first year of life. The overall OR for the dose-response analysis was 1.16 for each additional course of antibiotics; however, this association was not significantly stronger in the retrospective studies (OR, 1.37) relative to the prospective studies (OR, 1.07). Penelitian ini membuktikan bahwa pemberian antibiotika pada bayi merupakan faktor risiko untuk timbulnya asma pada anak2. Namun karena keterbatasan data, diperlukan penelitian lebih lanjut untuk mengkonfirmasi temuan ini.

Sunday, April 09, 2006

Kedele mengurangi risiko patah tulang

Prospective Cohort Study of Soy Food Consumption and Risk of Bone Fracture Among Postmenopausal Women, Xianglan Zhang, MD, MPH; Xiao-Ou Shu, MD, PhD; Honglan Li, MD; Gong Yang, MD, MPH; Qi Li, MS, MD; Yu-Tang Gao, MD; Wei Zheng, MD, PhD Arch Intern Med. 2005;165:1890-1895. September 12, 2005. © 2005 American Medical Association. Penelitian kohort prospektif ini bertujuan untuk mengetahui hubungan antara konsumsi kedele (soy food) dengan risiko patah tulang pada wanita pasca menopause. Penelitian ini berlangsung di Cina dari tahun 1997 sampai 2000, melibatkan 75.000 wanita pasca menopause, berusia 40-70 tahun, yang tidak menderita keganasan maupun riwayat patah tulang sebelumnya. Hasil penelitian mendapatkan risiko relatif (RR) patah tulang adalah 1.00, 0.72, 0.69, 0.64, dan 0.63 sesuai kuintil (quintiles) asupan protein kedele (P<0.001 for trend). Jadi semakin tinggi asupan kedele semakin kecil risiko patah tulang dan sebaliknya. Hasil penelitian ini menyimpulkan bahwa asupan produk kedele terbukti dapat mengurangi risiko patah tulang pada wanita pasca-menopause, terutama pada tahun-tahun awal pasca menopause.