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.