Thursday, December 13, 2007

Serat serealia mengurangi risiko diabetes tipe 2

Kejadian diabetes tipe 2 dalam masyarakat AS berkulit hitam telah mencapai tingkat yang memprihatinkan. Pola diet berkait erat dengan budaya masyarakat setempat. Namun dalam penelitian2 terdahulu hubungan asupan karbohidrat dan risiko diabetes tipe 2 belum dapat dijelaskan.

 

Penelitian kohort ini hendak menilai hubungan antara indeks glikemik, glycemic load, dan serat serealia terhadap risiko terjadinya diabetes tipe 2. Penelitian melibatkan 59 ribu wanita kulit hitam di AS mulai tahun 1995 dan diikuti selama 8 tahun.

 

Hasil penelitian menunjukkan bahwa indeks glikemik berasosiasi positif terhadap risiko diabetes. Serat serealia berhubungan terbalik dengan risiko diabetes tipe 2.

 

Sehingga disimpulkan bahwa peningkatan kadar serat serealia dalam makanan merupakan cara efektif untuk menurunkan risiko diabetes tipe 2.

 

 

Arch Intern Med 26 November 2007;167(20):2304-2309. © 2007 American Medical

Glycemic Index, Glycemic Load, and Cereal Fiber Intake and Risk of Type 2 Diabetes in US Black Women,

Supriya Krishnan, Lynn Rosenberg, Martha Singer, Frank B. Hu, Luc Djoussé, L. Adrienne Cupples, Julie R. Palmer.

Background  Previous studies of carbohydrate quality and risk of type 2 diabetes mellitus have yielded inconsistent findings. Because diet is in part culturally determined, a study of dietary factors in US black women is of interest.

Methods  We used data from the Black Women's Health Study, a prospective cohort study of 59 000 US black women, to examine the association of glycemic load, glycemic index, and cereal fiber with risk of type 2 diabetes. Diet was assessed at baseline in 1995 with a modified version of the National Cancer Institute–Block food frequency questionnaire.

Results  During 8 years of follow-up, there were 1938 incident cases of diabetes. Cox proportional hazards models were used to estimate incidence rate ratios (IRRs) for quintiles of dietary factors, while controlling for lifestyle and dietary factors. Glycemic index was positively associated with the risk of diabetes: the IRR for the highest quintile relative to the lowest was 1.23 (95% confidence interval [CI], 1.05-1.44). Cereal fiber intake was inversely associated with risk of diabetes, with an IRR of 0.82 (95% CI, 0.70-0.96) for the highest vs lowest quintiles of intake. Stronger associations were seen among women with a body mass index (calculated as weight in kilograms divided by height in meters squared) lower than 25: IRRs for the highest vs lowest quintile were 1.91 (95% CI, 1.16-3.16) for glycemic index (P value for interaction, .12) and 0.41 (95% CI, 0.24-0.72) for cereal fiber intake (P value for interaction, .05).

Conclusion  Increasing cereal fiber in the diet may be an effective means of reducing the risk of type 2 diabetes, a disease that has reached epidemic proportions in black women.

Friday, November 30, 2007

Dark chocolate dilates the coronaries

Penelitian acak tersamar berganda ini bertujuan untuk menilai efek antioksidan -yang banyak terkandung dalam dark chocolate (kandungan cocoa 70%)- terhadap pembuluh darah koroner dan agregasi trombosit.

 

Hasil penelitian menunjukkan pelebaran diameter arteri koronaria 2 jam setelah pemberian dark chocolate, dan penurunan agregasi trombosit.

 

Disimpulkan bahwa dark chocolate dapat men-dilatasi arteri koronaria, memperbaiki vaskularisasi koroner, dan menurunkan agregasi trombosit 2 jam pasca konsumsi. Efek ini sejalan dengan penurunan stres oksidatif dan berkorelasi positif dengan kadar epicatechin.

 

Circulation. 2007;116:2376-2382. 20 November 2007 © 2007 American Heart Association, Inc.
Dark Chocolate Improves Coronary Vasomotion and Reduces Platelet Reactivity. Andreas J. Flammer, MD; Frank Hermann, MD; Isabella Sudano, MD, PhD; Lukas Spieker, MD; Matthias Hermann, MD; Karen A. Cooper, MSc, PhD; Mauro Serafini, PhD; Thomas F. Lüscher, MD; Frank Ruschitzka, MD; Georg Noll, MD; Roberto Corti, MD
 

Background— Dark chocolate has potent antioxidant properties. Coronary atherosclerosis is promoted by impaired endothelial function and increased platelet activation. Traditional risk factors, high oxidative stress, and reduced antioxidant defenses play a crucial role in the pathogenesis of atherosclerosis, particularly in transplanted hearts. Thus, flavonoid-rich dark chocolate holds the potential to have a beneficial impact on graft atherosclerosis.

Methods and Results— We assessed the effect of flavonoid-rich dark chocolate compared with cocoa-free control chocolate on coronary vascular and platelet function in 22 heart transplant recipients in a double-blind, randomized study. Coronary vasomotion was assessed with quantitative coronary angiography and cold pressor testing before and 2 hours after ingestion of 40 g of dark (70% cocoa) chocolate or control chocolate, respectively. Two hours after ingestion of flavonoid-rich dark chocolate, coronary artery diameter was increased significantly (from 2.36±0.51 to 2.51±0.59 mm, P<0.01), whereas it remained unchanged after control chocolate. Endothelium-dependent coronary vasomotion improved significantly after dark chocolate (4.5±11.4% versus –4.3±11.7% in the placebo group, P=0.01). Platelet adhesion decreased from 4.9±1.1% to 3.8±0.8% (P=0.04) in the dark chocolate group but remained unchanged in the control group.

Conclusions— Dark chocolate induces coronary vasodilation, improves coronary vascular function, and decreases platelet adhesion 2 hours after consumption. These immediate beneficial effects were paralleled by a significant reduction of serum oxidative stress and were positively correlated with changes in serum epicatechin concentration.

Monday, November 19, 2007

Zat aditif dalam makanan menyebabkan anak hiperaktif

Peneliti di Inggris melakukan penelitian tersamar berganda untuk menilai apakah bahan pewarna dan aditif dalam makanan mempengaruhi perilaku anak-anak. Subyek penelitian adalah 153 anak berusia 3 tahun dan 144 anak berusia 8-9 tahun. Diberikan minuman yang mengandung natrium benzoate dan bahan aditif atau placebo.

 

Hasil penelitian menunjukkan bahwa zat aditif meningkatkan bermakna skor global hyperactivity aggregate (GHA) pada anak berusia 3 tahun maupun anak berusia 8-9 tahun.

 

Kesimpulan: makanan yang mengandung zat pewarna atau natrium benzoate (atau keduanya) dapat mempengaruhi perilaku anak-anak.

 

The Lancet online 6 September 2007(doi:10.1016/S0140-6736(07)61306-3) © 2007

Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial,

Donna McCann PhD, Angelina Barrett BSc, Alison Cooper MSc, Debbie Crumpler BSc, Lindy Dalen PhD, Kate Grimshaw MSc, Elizabeth Kitchin BSc, Kris Lok MSc, Lucy Porteous BSc, Emily Prince MSc, Prof Edmund Sonuga-Barke PhD, Prof John O Warner MD and Prof Jim Stevenson PhD. Correspondence to Prof Jim Stevenson jsteven@soton.ac.uk.

 

Background

We undertook a randomised, double-blinded, placebo-controlled, crossover trial to test whether intake of artificial food colour and additives (AFCA) affected childhood behaviour.

Methods

153 3-year-old and 144 8/9-year-old children were included in the study. The challenge drink contained sodium benzoate and one of two AFCA mixes (A or B) or a placebo mix. The main outcome measure was a global hyperactivity aggregate (GHA), based on aggregated z-scores of observed behaviours and ratings by teachers and parents, plus, for 8/9-year-old children, a computerised test of attention. This clinical trial is registered with Current Controlled Trials (registration number ISRCTN74481308). Analysis was per protocol.

Findings

16 3-year-old children and 14 8/9-year-old children did not complete the study, for reasons unrelated to childhood behaviour. Mix A had a significantly adverse effect compared with placebo in GHA for all 3-year-old children (effect size 0·20 [95% CI 0·01–0·39], p=0·044) but not mix B versus placebo. This result persisted when analysis was restricted to 3-year-old children who consumed more than 85% of juice and had no missing data (0·32 [0·05–0·60], p=0·02). 8/9-year-old children showed a significantly adverse effect when given mix A (0·12 [0·02–0·23], p=0·023) or mix B (0·17 [0·07–0·28], p=0·001) when analysis was restricted to those children consuming at least 85% of drinks with no missing data.

Interpretation

Artificial colours or a sodium benzoate preservative (or both) in the diet result in increased hyperactivity in 3-year-old and 8/9-year-old children in the general population.

Wednesday, November 7, 2007

Diet jaman batu baik untuk penderita gangguan toleransi glukosa

Penelitian diet untuk penderita diabetes selama ini terfokus pada asupan lemak, karbohidrat, dan serat.

Dalam penelitian ini, para ahli dari Swedia membandingkan diet Palaeolithic (diet jaman batu) terhadap diet Mediterranea -yang dianggap baik untuk penderita diabetes.

Hasil penelitian menunjukkan setelah 12 minggu penurunan kadar gula darah pada kelompok diet P lebih besar dibanding diet M. Penurunan lingkar pinggang kelompok diet P juga lebih besar dibanding kelompok diet M.

Disimpulkan bahwa diet jaman batu lebih unggul dalam hal memperbaiki toleransi glukosa untuk penderita diabetes tipe 2 dan gangguan toleransi glukosa.


Diabetologia Volume 50, Number 9 / September, 2007 (10.1007/s00125-007-0716-y) © Springer Berlin / Heidelberg.
A Palaeolithic diet improves glucose tolerance more than a Mediterranean-like diet in individuals with ischaemic heart disease,

S. Lindeberg , T. Jönsson, Y. Granfeldt, E. Borgstrand, J. Soffman, K. Sjöström and B. Ahrén.


Abstract

Aims/hypothesis Most studies of diet in glucose intolerance and type 2 diabetes have focused on intakes of fat, carbohydrate, fibre, fruits and vegetables. Instead, we aimed to compare diets that were available during human evolution with more recently introduced ones.

Methods Twenty-nine patients with ischaemic heart disease plus either glucose intolerance or type 2 diabetes were randomised to receive (1) a Palaeolithic ('Old Stone Age') diet (n=14), based on lean meat, fish, fruits, vegetables, root vegetables, eggs and nuts; or (2) a Consensus (Mediterranean-like) diet (n=15), based on whole grains, low-fat dairy products, vegetables, fruits, fish, oils and margarines. Primary outcome variables were changes in weight, waist circumference and plasma glucose AUC (AUC Glucose0–120) and plasma insulin AUC (AUC Insulin0–120) in OGTTs.

Results Over 12 weeks, there was a 26% decrease of AUC Glucose0–120 (p=0.0001) in the Palaeolithic group and a 7% decrease (p=0.08) in the Consensus group. The larger (p=0.001) improvement in the Palaeolithic group was independent (p=0.0008) of change in waist circumference (−5.6 cm in the Palaeolithic group, −2.9 cm in the Consensus group; p=0.03). In the study population as a whole, there was no relationship between change in AUC Glucose0–120 and changes in weight (r=−0.06, p=0.9) or waist circumference (r=0.01, p=1.0). There was a tendency for a larger decrease of AUC Insulin0–120 in the Palaeolithic group, but because of the strong association between change in AUC Insulin0–120 and change in waist circumference (r=0.64, p=0.0003), this did not remain after multivariate analysis.

Conclusions/interpretation A Palaeolithic diet may improve glucose tolerance independently of decreased waist circumference.

Wednesday, September 5, 2007

Apakah kopi menyebabkan hipertensi?

Kita sering mendengar anjuran agar jangan minum kopi menyebabkan darah tinggi.

 

Betulkah pendapat tersebut?

 

Selama ini penelitian tentang hubungan minum kopi dan hipertensi tidak dapat menyimpulkan secara tegas.

 

Penelitian terbaru ini meneliti hubungan minum kopi dengan pemberian obat antihipertensi.

 

Hasil penelitian menunjukan bahwa konsumsi >1 cangkir kopi perhari berhubungan dengan terapi antihipertensi. Namun konsumsi 8 cangkir kopi perhari tidak berhubungan dengan terapi antihipertensi.

 

Dengan demikian hubungan kopi dan hipertensi tetap belum jelas.

 

Coffee consumption and the incidence of antihypertensive drug treatment in Finnish men and women

 

Am J Clin Nutr August 2007;86:457-464. © American Society for Nutrition
Coffee consumption and the incidence of antihypertensive drug treatment in Finnish men and women, Gang Hu, Pekka Jousilahti, Aulikki Nissinen, Siamak Bidel, Riitta Antikainen and Jaakko Tuomilehto

 

Background: Only 2 prospective studies have previously investigated the association between coffee consumption and incident hypertension, and the findings are equivocal.

Objective: The objective was to determine the relation between coffee consumption and the incidence of antihypertensive drug treatment.

Design: We prospectively followed 24 710 Finnish subjects aged 25-64 y without a history of antihypertensive drug treatment, coronary heart disease, or stroke at baseline. Daily coffee consumption was assessed by questionnaires.

Results: During a mean follow-up period of 13.2 y, 2505 participants started antihypertensive drug treatment. The multivariate-adjusted (age, sex, study year, education, leisure-time physical activity, smoking, body mass index, high total cholesterol, history of diabetes, and alcohol, tea, fruit, vegetable, sausage, and bread consumption) hazard ratios for antihypertensive drug treatment associated with the amount of coffee consumed daily (0-1, 2-3, 4-5, 6-7, or 8 cups) were 1.00, 1.29 (95% CI: 1.09, 1.54), 1.26 (95% CI: 1.06, 1.49), 1.24 (95% CI: 1.04, 1.48), and 1.14 (95% CI: 0.94, 1.37) (P for trend = 0.024), respectively. This trend became marginally significant after additional adjustment for baseline systolic blood pressure (P for trend = 0.077).

Conclusions: The results indicate that coffee drinking seems to increase the risk of antihypertensive drug treatment, and this risk was higher in subjects with low-to-moderate coffee intakes; however, there was no significantly increased trend in drinkers of 1 cup (100 mL)/d or 8 cups/d.

Wednesday, August 22, 2007

Buah dan sayuran mencegah asma dan alergi

Penelitian ini membuktikan bahwa diet kaya buah2an, sayuran dan kacang2an (banyak terkandung dalam menu tradisional diet Mediterrania) pada anak2 dapat mengurangi gejala asma dan rhinitis.
 
 
 
Thorax 2007;62:677-683 August 2007. © 2007 BMJ Publishing Group Ltd & British Thoracic Society.
Protective effect of fruits, vegetables and the Mediterranean diet on asthma and allergies among children in Crete.  Leda Chatzi, Gianna Apostolaki, Ioannis Bibakis, Isabel Skypala, Vasilki Bibaki-Liakou, Nikolaos Tzanakis, Manolis Kogevinas and Paul Cullinan.

Background: Atopy is not uncommon among children living in rural Crete, but wheeze and rhinitis are rare. A study was undertaken to examine whether this discrepancy could be attributed to a high consumption of fresh fruit and vegetables or adherence to a traditional Mediterranean diet.

Methods: A cross-sectional survey was performed in 690 children aged 7–18 years in rural Crete. Parents completed a questionnaire on their child's respiratory and allergic symptoms and a 58-item food frequency questionnaire. Adherence to a Mediterranean diet was measured using a scale with 12 dietary items. Children underwent skin prick tests with 10 common aeroallergens.

Results: 80% of children ate fresh fruit (and 68% vegetables) at least twice a day. The intake of grapes, oranges, apples, and fresh tomatoes—the main local products in Crete—had no association with atopy but was protective for wheezing and rhinitis. A high consumption of nuts was found to be inversely associated with wheezing (OR 0.46; 95% CI 0.20 to 0.98), whereas margarine increased the risk of both wheeze (OR 2.19; 95% CI 1.01 to 4.82) and allergic rhinitis (OR 2.10; 95% CI 1.31 to 3.37). A high level of adherence to the Mediterranean diet was protective for allergic rhinitis (OR 0.34; 95% CI 0.18 to 0.64) while a more modest protection was observed for wheezing and atopy.

Conclusion: The results of this study suggest a beneficial effect of commonly consumed fruits, vegetables and nuts, and of a high adherence to a traditional Mediterranean diet during childhood on symptoms of asthma and rhinitis. Diet may explain the relative lack of allergic symptoms in this population.

Friday, June 29, 2007

Are people who regularly eat breakfast cereals slimmer than those who don't?

Sarapan - terutama dengan sereal - terbukti dapat menjaga berat badan ideal. Bagi yang ingin menjaga berat badan, lebih baik sarapan daripada menghindarinya yang akan menyebabkan rasa lapar intens.
 
 

Are people who regularly eat breakfast cereals slimmer than those who don't? A systematic review of the evidence

Nutrition Bulletin, Volume 32, Number 2, June 2007 , pp. 118-128(11) (doi: 10.1111/j.1467-3010.2007.00638.x). Blackwell Publishing

de la Hunty, A.; Ashwell, M.

 

Abstract:

Summary

There is growing evidence that people who eat breakfast regularly tend to be slimmer than those who skip breakfast. However, this is not a consistent finding and it is not true for all types of breakfast. Also the relationship with breakfast can disappear in studies when adjusted for breakfast cereal consumption, suggesting it is breakfast cereal that is driving the association. This systematic review, therefore, looked specifically at the relationship between breakfast cereal consumption and weight.

A systematic search of the literature identified nine references looking at the relationship between the consumption of breakfast cereals and BMI as an outcome measure.

Five of the nine included studies were in adults. These studies consistently showed that people who eat breakfast cereals regularly tend to have a lower BMI and are less likely to be overweight than those who do not eat breakfast cereals regularly. Although not all of the results were statistically significant, they all point in the same direction. There was no evidence that regular breakfast cereal consumers have lower daily energy intakes than infrequent consumers.

Four of the nine included studies were in children. As for adults, the evidence from the included studies is consistent that children who eat breakfast cereals regularly tend to have a lower BMI and are less likely to be overweight than those who eat breakfast cereals infrequently. There was no evidence that children who consume breakfast cereals regularly have lower energy intakes than infrequent cereal consumers.

This systematic review considered whether the relationship between breakfast cereal consumption and weight is likely to be mediated either through lower energy intakes or higher energy expenditures. We found no clear evidence for this or for any other proposed mechanism. The relationship could arise out of confounding by lifestyle factors.

There is consistent evidence of an association between breakfast cereal consumption and a healthy weight, but limited evidence for any proposed mechanism that would point to it being a causal relationship.

Monday, June 18, 2007

Fw: Low-carbohydrate, high-protein diet and long-term survival in a general population cohort

European Journal of Clinical Nutrition. 2007;61:575 - 581. May 2007. ©2007
Nature Publishihg Group.
Low-carbohydrate - high-protein diet and long-term survival in a general
population cohort,
A Trichopoulou, T Psaltopoulou, P Orfanos, C-C Hsieh, and D Trichopoulos

Diet rendah karbohidrat tinggi protein (RKTP) banyak digunakan untuk
menurunkan berat badan. Para ahli di Yunani ingin mengetahui hubungan diet
RKTP dengan kesehatan.

Dilakukan penelitian kohort terhadap >23.000 laki2 dan perempuan sehat
berusia 20-86 tahun.

Orang yang pola dietnya tinggi karbohidrat mempunyai risiko mortalitas yang
lebih rendah. Sebaliknya mereka yang diet tinggi protein mempunyai risiko
mortalitas lebih tinggi.

Sehingga disimpulkan bahwa diet RKTP dalam jangka panjang meningkatkan
risiko kematian.


Abstract


Objective:

We have evaluated the effects on mortality of habitual low
carbohydrate-high-protein diets that are thought to contribute to weight
control.


Design:

Cohort investigation.


Setting:

Adult Greek population.


Subjects methods:

Follow-up was performed from 1993 to 2003 in the context of the Greek
component of the European Prospective Investigation into Cancer and
nutrition. Participants were 22 944 healthy adults, whose diet was assessed
through a validated questionnaire. Participants were distributed by
increasing deciles according to protein intake or carbohydrate intake, as
well as by an additive score generated by increasing decile intake of
protein and decreasing decile intake of carbohydrates. Proportional hazards
regression was used to assess the relation between high protein, high
carbohydrate and the low carbohydrate-high protein score on the one hand and
mortality on the other.


Results:

During 113 230 persons years of follow-up, there were 455 deaths. In models
with energy adjustment, higher intake of carbohydrates was associated with
significant reduction of total mortality, whereas higher intake of protein
was associated with nonsignificant increase of total mortality (per decile,
mortality ratios 0.94 with 95% CI 0.89 -0.99, and 1.02 with 95% CI
0.98 -1.07 respectively). Even more predictive of higher mortality were high
values of the additive low carbohydrate-high protein score (per 5 units,
mortality ratio 1.22 with 95% CI 1.09 -to 1.36). Positive associations of
this score were noted with respect to both cardiovascular and cancer
mortality.


Conclusion:

Prolonged consumption of diets low in carbohydrates and high in protein is
associated with an increase in total mortality.

Friday, April 20, 2007

Konsumsi daging meningkatkan risiko kanker payudara

Para ahli di Inggris melakukan penelitian kohort terhadap lebih dari 35 ribu wanita berumur 35-69 tahun selama lebih dari 3 tahun. Mereka menemukan bahwa konsumsi daging berhubungan dengan kanker payudara.

Wanita premenopaus dengan tingkat konsumsi daging tertinggi mempunyai risiko 20% lebih tinggi untuk terjadinya kanker payudara dibanding kelompok vegetarian. Sedangkan wanita pasca menopause dengan tingkat konsumsi daging olahan (processed meat) tertinggi mempunyai risiko 64% lebih tinggi untuk terjadinya kanker payudara dibanding kelompok vegetarian.

Kesimpulan wanita (pra dan pasca menopause) dengan tingkat konsumsi daging tinggi menghadapi peningkatan risiko kanker payudara.

Abstract

Meat consumption and risk of breast cancer in the UK Women's Cohort Study

E F Taylor, V J Burley, D C Greenwood and J E Cade

British Journal of Cancer (2007) 96, 1139-1146.
doi:10.1038/sj.bjc.6603689

We performed a survival analysis to assess the effect of meat consumption and meat type on the risk of breast cancer in the UK Women's Cohort Study. Between 1995 and 1998 a cohort of 35 372 women was recruited, aged between 35 and 69 years with a wide range of dietary intakes, assessed by a 217-item food frequency questionnaire. Hazard ratios (HRs) were estimated using Cox regression adjusted for known confounders. High consumption of total meat compared with none was associated with premenopausal breast cancer, HR=1.20 (95% CI: 0.86-1.68), and high non-processed meat intake compared with none, HR=1.20 (95% CI: 0.86-1.68). Larger effect sizes were found in postmenopausal women for all meat types, with significant associations with total, processed and red meat consumption. Processed meat showed the strongest HR=1.64 (95% CI: 1.14-2.37) for high consumption compared with none. Women, both pre- and postmenopausal, who consumed the most meat had the highest risk of breast cancer.

Tuesday, March 27, 2007

Diet Atkins Efektif untuk Menurunkan Berat Badan

Seiring peningkatan insiden kelebihan berat badan dan obesitas muncul pula berbagai teori diet untuk menurunkan berat badan.

Untuk menilai efektifitas diet terhadap penurunan berat badan dan variabel metabolisme para ahli membandingkan 4 macam spektrum diet, mulai dari diet rendah karbohidrat tinggi lemak (Atkins) sampai diet tinggi karbohidrat rendah lemak.

Partisipan menjalankan diet yang ditentukan selama 12 bulan sambil dilakukan monitoring. Setelah 12 bulan ternyata kelompok diet Atkins mengalami penurunan berat badan yang paling besar dibanding diet yang lain. Demikian pula untuk profil lipid, persen lemak tubuh, rasio pinggang panggul, kadar insulin, kadar gula darah dan tekanan darah, kelompok diet Atkins lebih baik dibanding diet yang lain.

Sehingga dapat disimpulkan bahwa diet rendah karbohidrat tinggi protein dan lemak efektif untuk menurunkan berat badan, namun demikian benefit dan risiko jangka panjang masih memerlukan penelitian lebih lanjut.

Namun harus diingat bahwa penelitian ini dilakukan pada wanita premenopause di USA dengan pola diet yang memang rendah karbohidrat. Untuk populasi orang Indonesia hasilnya belum tentu sama.


Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight
and Related Risk Factors Among Overweight Premenopausal Women
The A TO Z Weight Loss Study: A Randomized Trial

Christopher D. Gardner, PhD; Alexandre Kiazand, MD; Sofiya Alhassan, PhD;
Soowon Kim, PhD; Randall S. Stafford, MD, PhD; Raymond R. Balise, PhD;
Helena C. Kraemer, PhD; Abby C. King, PhD

JAMA. 2007;297:969-977.

Context Popular diets, particularly those low in carbohydrates, have challenged current recommendations advising a low-fat, high-carbohydrate diet for weight loss. Potential benefits and risks have not been tested adequately.

Objective To compare 4 weight-loss diets representing a spectrum of low to high carbohydrate intake for effects on weight loss and related metabolic variables.

Design, Setting, and Participants Twelve-month randomized trial conducted in the United States from February 2003 to October 2005 among 311 free-living, overweight/obese (body mass index, 27-40) nondiabetic, premenopausal women.

Intervention Participants were randomly assigned to follow the Atkins (n =77), Zone (n = 79), LEARN (n = 79), or Ornish (n = 76) diets and received weekly instruction for 2 months, then an additional 10-month follow-up.

Main Outcome Measures Weight loss at 12 months was the primary outcome. Secondary outcomes included lipid profile (low-density lipoprotein, high-density lipoprotein, and non-high-density lipoprotein cholesterol, and triglyceride levels), percentage of body fat, waist-hip ratio, fasting insulin and glucose levels, and blood pressure. Outcomes were assessed at months 0, 2, 6, and 12. The Tukey studentized range test was used to adjust for multiple testing.

Results Weight loss was greater for women in the Atkins diet group compared with the other diet groups at 12 months, and mean 12-month weight loss was significantly different between the Atkins and Zone diets (P<.05). Mean 12-month weight loss was as follows: Atkins, -4.7 kg (95% confidence interval [CI], -6.3 to -3.1 kg), Zone, -1.6 kg (95% CI, -2.8 to -0.4 kg), LEARN, -2.6 kg (-3.8 to -1.3 kg), and Ornish, -2.2 kg (-3.6 to -0.8 kg). Weight loss was not statistically different among the Zone, LEARN, and Ornish groups. At 12 months, secondary outcomes for the Atkins group were comparable with or more favorable than the other diet groups.

Conclusions In this study, premenopausal overweight and obese women assigned to follow the Atkins diet, which had the lowest carbohydrate intake, lost more weight and experienced more favorable overall metabolic effects at 12 months than women assigned to follow the Zone, Ornish, or LEARN diets. While questions remain about long-term effects and mechanisms, a low-carbohydrate, high-protein, high-fat diet may be considered a feasible alternative
recommendation for weight loss.

Trial Registration clinicaltrials.gov Identifier: NCT00079573

Tuesday, March 20, 2007

Suplemen Antioksidan Meningkatkan Mortalitas

Suplemen antioksidan yang mengandung salah satu atau kombinasi dari
selenium, betakaroten, vitamin A, vitamin E dan vitamin C, banyak digunakan
untuk pencegahan berbagai penyakit.

Para ahli ingin mengetahui efek suplementasi antioksidan terhadap mortalitas
(kematian) penggunanya dengan melakukan meta-analisis.

Hasil penelitian ternyata penggunaan betakaroten, vitamin A dan vitamin E
dapat meningkatkan mortalitas. Sedangkan untuk vitamin C dan Selenium perlu
penelitian lebih lanjut.

Dengan demikian dapat disimpulkan bahwa pemberian suplementasi vitamin
sekalipun perlu hati-hati karena dapat membawa efek yang tidak diinginkan.

Mortality in Randomized Trials of Antioxidant Supplements for Primary and
Secondary Prevention

JAMA. 2007;297:842-857.
Goran Bjelakovic, MD, DrMedSci; Dimitrinka Nikolova, MA; Lise Lotte Gluud,
MD, DrMedSci; Rosa G. Simonetti, MD; Christian Gluud, MD, DrMedSci

Context Antioxidant supplements are used for prevention of several diseases.


Objective To assess the effect of antioxidant supplements on mortality in
randomized primary and secondary prevention trials.

Data Sources and Trial Selection We searched electronic databases and
bibliographies published by October 2005. All randomized trials involving
adults comparing beta carotene, vitamin A, vitamin C (ascorbic acid),
vitamin E, and selenium either singly or combined vs placebo or vs no
intervention were included in our analysis. Randomization, blinding, and
follow-up were considered markers of bias in the included trials. The effect
of antioxidant supplements on all-cause mortality was analyzed with
random-effects meta-analyses and reported as relative risk (RR) with 95%
confidence intervals (CIs). Meta-regression was used to assess the effect of
covariates across the trials.

Data Extraction We included 68 randomized trials with 232 606 participants
(385 publications).

Data Synthesis When all low- and high-bias risk trials of antioxidant
supplements were pooled together there was no significant effect on
mortality (RR, 1.02; 95% CI, 0.98-1.06). Multivariate meta-regression
analyses showed that low-bias risk trials (RR, 1.16; 95% CI, 1.05-1.29) and
selenium (RR, 0.998; 95% CI, 0.997-0.9995) were significantly associated
with mortality. In 47 low-bias trials with 180 938 participants, the
antioxidant supplements significantly increased mortality (RR, 1.05; 95% CI,
1.02-1.08). In low-bias risk trials, after exclusion of selenium trials,
beta carotene (RR, 1.07; 95% CI, 1.02-1.11), vitamin A (RR, 1.16; 95% CI,
1.10-1.24), and vitamin E (RR, 1.04; 95% CI, 1.01-1.07), singly or combined,
significantly increased mortality. Vitamin C and selenium had no significant
effect on mortality.

Conclusions Treatment with beta carotene, vitamin A, and vitamin E may
increase mortality. The potential roles of vitamin C and selenium on
mortality need further study.

Author Affiliations: The Cochrane Hepato-Biliary Group, Copenhagen Trial
Unit, Center for Clinical Intervention Research, Copenhagen University
Hospital, Rigshospitalet, Copenhagen, Denmark (Drs Bjelakovic, L. L. Gluud,
Simonetti, and C. Gluud and Ms Nikolova); Department of Internal Medicine,
Gastroenterology and Hepatology, University of Nis, Nis, Serbia (Dr
Bjelakovic); and Divisione di Medicina, Ospedale V. Cervello, Palermo, Italy
(Dr Simonetti).

Wednesday, January 31, 2007

Konsumsi ikan, buah dan sayuran menurunkan insiden tromboemboli v ena

Penelitian ini dilakukan secara prospektif selama 12 tahun terhadap hampir
15 ribu orang dewasa.

Hasil penelitian menunjukkan bahwa konsumsi ikan, buah dan sayuran dapat
menurunkan insiden tromboemboli vena. Sedangkan konsumsi daging dan produk
olahannya justru meningkatkan insiden tromboemboli vena.

Kesimpulan dari penelitian ini adalah meningkatkan konsumsi ikan (sebagai
sumber protein hewani, pengganti daging), buah dan sayuran dapat menurunkan
insiden tromboemboli vena.

Circulation. 2007;115:188195. January 16, 2007 © 2007 American Heart
Association, Inc.
Greater Fish, Fruit, and Vegetable Intakes Are Related to Lower Incidence of
Venous Thromboembolism.
The Longitudinal Investigation of Thromboembolism Etiology,
Lyn M. Steffen, Aaron R. Folsom, Mary Cushman, David R. Jacobs, Jr, Wayne D.
Rosamond.

Background- Little is known about the role of dietary intake in the
development of deep vein thrombosis or pulmonary embolus (venous
thromboembolism [VTE]). Homocysteine, factor VIII, and von Willebrand factor
levels, risk factors for VTE, are influenced by dietary intake. We tested
the hypothesis that foods rich in B vitamins and n-3 fatty acids are
negatively associated and meat intake is positively associated with
incidence of VTE.

Methods and Results- In a prospective study over 12 years, 14 962
middle-aged adults participating in the Atherosclerosis Risk in Communities
study were followed up for incident VTE. All hospitalizations were
identified, and 196 VTEs were validated by chart review. A food frequency
questionnaire assessed dietary intake at baseline and year 6. In separate
proportional hazards regression analyses, risk of developing VTE was
computed across quintiles of selected nutrients, major food groups, and the
Western diet pattern, with adjustment for demographic and lifestyle factors,
body mass index, and diabetes. Hazard ratios and 95% confidence intervals of
VTE incidence across quintiles of fruit and vegetable intake were 1.0
(reference), 0.73 (0.48 to 1.11), 0.57 (0.37 to 0.90), 0.47 (0.29 to 0.77),
and 0.59 (0.36 to 0.99) (Ptrend=0.03). Eating fish 1 or more times per week
was associated with 30% to 45% lower incidence of VTE for quintiles 2 to 5
compared with quintile 1, suggestive of a threshold effect. Hazard ratios of
VTE across quintiles of red and processed meat intake were 1.0, 1.24 (0.78
to 1.98), 1.21 (0.74 to 1.98), 1.09 (0.64 to 1.87), and 2.01 (1.15 to 3.53)
(Ptrend=0.02). Hazard ratios were attenuated only slightly after adjustment
for factors VIIc and VIIIc and von Willebrand factor.

Conclusions- A diet including more plant food and fish and less red and
processed meat is associated with a lower incidence of VTE.

Friday, January 19, 2007

Bawang merah dan bawang putih dapat mencegah kanker

American Journal of Clinical Nutrition, Vol. 84, No. 5, 1027-1032, November
2006. © 2006 American Society for Nutrition. Onion and garlic use and human
cancer. Carlotta Galeone, Claudio Pelucchi, Fabio Levi, Eva Negri, Silvia
Franceschi, Renato Talamini, Attilio Giacosa and Carlo La Vecchia

Masyarakat Asia banyak menggunakan bawang merah (Allium cepa) dan bawang
putih (Allium sativum) dalam makanan sehari2. Tentang khasiat bawang merah
dan bawang putih juga telah banyak diteliti di China. Para ahli di Italia
mengadakan penelitian untuk membuktikan khasiat bawang merah dan bawang
putih.

Mereka mendapatkan bahwa kelompok orang yang banyak mengkonsumsi bawang
merah dan bawang putih dapat menurunkan risiko terjadinya kanker rongga
mulut, kanker tenggorokan, kanker esofagus, kanker kolorektal (usus besar),
kanker larynx, kanker payudara, kanker prostat, dan kanker ginjal.

Kesimpulan konsumsi bawang merah dan bawang putih terbukti dapat menurunkan
risiko kanker.

Abstract

Background: Interest in the potential benefits of allium vegetables, in
particular, onion (Allium cepa) and garlic (Allium sativum), has its origin
in antiquity, but the details of these benefits are still open to
discussion.

Objective: We investigated the role of allium vegetables in the etiology of
various neoplasms. Previous data are scanty and are based mainly on Chinese
studies.

Design: Using data from an integrated network of Italian and Swiss
case-control studies, we analyzed the relation between frequency of onion
and garlic use and cancer at several sites. We calculated odds ratios (ORs)
by using multivariate logistic regression models that were adjusted for
energy intake and other major covariates.

Results: Consumption of onions varied between 0-14 and 0-22 portions/wk
among cases and controls, respectively. The multivariate ORs for the highest
category of onion and garlic intake were, respectively, 0.16 and 0.61 for
cancer of the oral cavity and pharynx, 0.12 and 0.43 for esophageal cancer,
0.44 and 0.74 for colorectal cancer, 0.17 and 0.56 for laryngeal cancer,
0.75 and 0.90 for breast cancer, 0.27 and 0.78 for ovarian cancer, 0.29 and
0.81 for prostate cancer, and 0.62 and 0.69 for renal cell cancer.

Conclusions: This uniquely large data set from southern European populations
shows an inverse association between the frequency of use of allium
vegetables and the risk of several common cancers. Allium vegetables are a
favorable correlate of cancer risk in Europe.

Friday, January 12, 2007

Biaya kesehatan untuk anak obes lebih mahal

Bagi para orang tua yang masih menginginkan anaknya bertubuh gemuk, temuan
terbaru ini layak disimak.

Para peneliti di USA menemukan bahwa biaya kesehatan untuk anak dengan
obesitas lebih mahal dibanding anak normal, karena lebih sering mengunjungi
dokter dan melakukan pemeriksaan laboratorium.

Hal yang sama berlaku juga pada orang dewasa dengan obesitas. Disebutkan
pula bahwa 80% anak usia 12 tahun dengan obesitas akan berlanjut menjadi
obesitas dewasa.

Health Care Expenditures Significantly Higher For Children With Obesity
Sarah E. Hampl, M.D., et al.
Arch Pediatr Adolesc Med. 2007;161:11-14

Children and adolescents who are obese or overweight have higher health care
utilization and a significantly higher average of health care charges than
their healthy-weight peers, according to a report in the January issue of
Archives of Pediatrics & Adolescent Medicine, one of the JAMA/Archives
journals.

According to background information in the article, 30 percent of children
in the United States are obese or overweight with six in ten having at least
one risk factor for cardiovascular disease and 25 percent having more than
two risk factors for the disease. The authors note that more than 80 percent
of obese 12-year-olds will carry their overweight status into adulthood.

Sarah E. Hampl, M.D., and colleagues at Children's Mercy Hospitals and
Clinics and the University of Missouri-Kansas City School of Medicine
analyzed data from 8,404 patients age 5 to 18 who attended a primary care
clinic in the Midwest for well-child care visits during 2002 and 2003. Body
mass index (BMI) was calculated with patients' height and weight
information. Four weight categories were used in the study: patients with a
BMI in the 95th percentile or higher for their age and sex with a discharge
diagnosis of obesity, patients with a BMI in the 95th percentile or higher
for their age and sex without a diagnosis of obesity, patients with BMI
between the 85th and 94th percentiles classified as overweight and patients
with BMIs lower than the 85th percentile classified as healthy weight.

Health care resource utilization was measured for each category and included
the number of health care visits and blood tests that occurred within a year
from each patient's initial visit. Health care expenditures were determined
by charge data obtained through the billing system of health care resources.
Factors associated with the diagnosis of obesity were also examined.

Based on the patients' BMI, 17.8 percent were overweight and 21.9 percent
were obese. Of the obese children, only 42.9 percent had a discharge
diagnosis of obesity, suggesting a significant rate of underdiagnosis. "When
obesity was present, being female, older and insured by Medicaid were
associated with a higher probability of having diagnosed obesity," the
authors write.

A significantly higher rate of utilization of laboratory services by
overweight and obese children was found when compared to their
healthy-weight peers. This increase was most notable for children with
diagnosed obesity. "We speculate that this increase reflects primary care
provider compliance with expert committee recommendations for laboratory
evaluation of obese children and adolescents," the authors write. "Compared
with their healthy-weight peers, children with overweight, diagnosed obesity
and undiagnosed obesity had significantly higher charges, with the highest
for the diagnosed obesity category," with an average adjusted difference of
$172.

"This finding is perhaps reflective of primary care provider intent to
detect and treat comorbid conditions. This trend of increased health care
utilization, observed even in children younger than 10 years, is similar to
the trends seen in adult patients," the authors conclude. "Efforts to
continue to educate primary care providers regarding the diagnosis of
obesity and early interventions to address obesity in children are
warranted."