膳食纖維可能協助預防體重、腰圍增加

作者：Laurie Barclay  
出處：WebMD醫學新聞

　　January 6, 2010 — 根據一項在2009年12月16日線上發表於美國臨床營養期刊上的前瞻性研究結果，膳食纖維可能協助預防體重與腰圍增加。
　　
　　荷蘭Bilthoven國家公共衛生與環境機構的Huaidong Du與其同事們寫到，膳食纖維在預防肥胖上可能扮演角色。直到現在，仍然沒有太多關於不同來源的纖維在體重變化上角色的研究。
　　
　　這項研究的目的在於評估膳食纖維、穀類纖維、水果與蔬菜纖維以及體重、腰圍變化的關係。這個試驗族群包括89,432位歐洲受試者，年齡介於20~78歲，這些病患在試驗前沒有癌症、心血管疾病與糖尿病。使用經確效、國家特定、飲食頻率問卷來取得飲食資訊。平均追蹤時間為6.5年。在每個研究中心，校正後續追蹤時間、其他飲食變項、試驗前體態、流行病學、與生活型態因子後，進行多重線性迴歸，且以隨機效應分析合併估計。
　　
　　纖維總攝取量以及之後的體重與腰圍變化成反向關係。纖維總攝取量每天增加10公克，體重改變綜合估計為每年-39公克（95%信賴區間[CI]為每年-71~-7公克），腰圍變化為每年-0.08公分（95% CI為每年-0.11~-0.05公分）。
　　
　　來自穀類的纖維攝取每天增加10公克，體重變化每年-77公克（95% CI為每年-127~-26公克），腰圍變化為每年-0.10公分（95% CI為每年-0.18~-0.02公分）。水果及蔬菜纖維與體重變化並沒有相關。然而，攝取水果及蔬菜纖維和腰圍變化之間的關係，與總纖維攝取及穀類纖維所看到的相似。
　　
　　這項研究的限制包括用於收集後續追蹤體態學資料的方法不同，因為後續追蹤的體重與腰圍量測是自行通報的，而不是在6個研究中心其中4個進行。除此之外，只有在試驗前收集一次飲食資訊，這排除了研究纖維攝取與體重及腰圍變化的並存關係。
　　
　　研究作者們寫到，我們的發現可能支持了攝取較多膳食纖維在預防體重和腰圍增加上可能的好處，特別是穀類纖維。雖然在我們的研究中，以個體來看，觀察到的效果相當小，但是在我們的研究中，觀察到纖維對體重的效應在公共衛生上可能是有關連的。
　　
　　DiOGenes（Diet、Obesity與Genes）計畫贊助這項研究，這是項由歐洲社群贊助的計畫。研究作者們表示已無相關資金上的往來。


Dietary Fiber May Help Prevent Body Weight, Waist Circumference Gain

By Laurie Barclay
Medscape Medical News

January 6, 2010 — Dietary fiber may help prevent gain in body weight and waist circumference, according to the results of a prospective cohort study reported online in the December 16, 2009, issue of the American Journal of Clinical Nutrition.

"Dietary fiber may play a role in obesity prevention," write Huaidong Du, from the National Institute for Public Health and the Environment in Bilthoven, the Netherlands, and colleagues. "Until now, the role that fiber from different sources plays in weight change had rarely been studied."

The goal of this study was to evaluate the relationship of total dietary fiber, cereal fiber, and fruit and vegetable fiber with changes in weight and waist circumference. The study cohort consisted of 89,432 European participants, aged 20 to 78 years, without cancer, cardiovascular disease, and diabetes at baseline. Validated, country-specific, food-frequency questionnaires were used to obtain dietary information. Average duration of follow-up was 6.5 years. In each center studied, multiple linear regression analysis was performed, and estimates were combined with random-effect meta-analyses, after adjustment for follow-up duration; other dietary variables; and baseline anthropometric, demographic, and lifestyle factors.

There was an inverse association of total fiber intake with subsequent change in weight and in waist circumference. For each 10-g/day increase in total fiber intake, the pooled estimate was –39 g/year (95% confidence interval [CI], –71 to –7 g/year) for weight change and –0.08 cm/year (95% CI, –0.11 to –0.05 cm/year) for waist circumference change.

For each 10-g/day increase in fiber intake from cereals, there was a weight change of –77 g/year (95% CI, –127 to –26 g/year) and change in waist circumference of –0.10 cm/year (95% CI, –0.18 to –0.02 cm/year). Fruit and vegetable fiber was not associated with weight change. However, the association of fruit and vegetable fiber intake with change in waist circumference was similar to that seen for intake of total dietary fiber and cereal fiber.

Limitations of this study include difference in methodologies used to collect anthropometric data at follow-up because weight and waist circumference measurements at follow-up were self-reported instead of measured at 4 of 6 study centers. In addition, dietary information was collected only once at baseline, which precluded investigating the concurrent association between changes in fiber intake and changes in weight and waist circumference.

"Our finding may support a beneficial role of higher intake of dietary fiber, especially cereal fiber, in prevention of body-weight and waist circumference gain," the study authors write. "Although the observed effect was rather small in our study when judged on the individual level, the effect of fiber on weight change observed in our study may be of public health relevance."

The DiOGenes (Diet, Obesity, and Genes) project, which was supported by the European Community, supported this study. The study authors have disclosed no relevant financial relationships.
Am J Clin Nutr. Published online December 16, 2009