Voedingsvezels tegen overgewicht*
Uit een Europese studie onder ruim 89.000 personen van 20-78 jaar blijkt dat extra inname van
vezelrijke voeding kan helpen tegen overgewicht en een dikke buik. Tegen overgewicht hielp hoofdzakelijk extra voedingsvezels van granen. Voor een kleinere taille hielpen zowel voedingsvezels van
granen als van groenten en
fruit.
Dietary Fiber May Help Prevent Body Weight, Waist Circumference Gain
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 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. Abstract
Clinical Context
Dietary fiber, obtained from edible portions of plant foods that are resistant to digestion and absorption in the human small intestine, undergoes complete or partial fermentation in the large intestine. Different physiologic mechanisms have been proposed by which dietary fiber may facilitate control of body weight.
Based on results of well-controlled intervention studies and large cohort studies, dietary fiber does appear to improve body weight regulation. However, the physiologic effects of fiber may vary based on its origin or sources, with cereal, fruit, and vegetable fiber potentially having different effects.
Study Highlights
· The goal of this study was to determine whether the intake of dietary fiber, in total and by food sources, is associated with long-term change in weight and waist circumference.
· The study cohort was a population-based, prospective sample of 89,432 Europeans in 5 different countries.
· Age range was 20 to 78 years, and participants were free of cancer, cardiovascular disease, and diabetes at baseline.
· Dietary data were collected with use of validated, country-specific, food-frequency questionnaires.
· Average duration of follow-up was 6.5 years.
· At 4 of 6 study centers, weight and waist circumference measurements at follow-up were self-reported instead of measured.
· Multiple linear regression analysis was performed at each of the 6 centers studied.
· After adjustment for follow-up duration; other dietary variables; and baseline anthropometric, demographic, and lifestyle factors, estimates were combined with use of random-effect meta-analyses.
· There was a moderate to large amount of heterogeneity across study centers, but the reason for this was not completely known.
· Total fiber intake was inversely associated with subsequent change in weight and waist circumference.
· For each 10-g/day increase in total fiber intake, the pooled estimate was –39 g/year (95% 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 a 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.
· 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.
· The investigators concluded that higher intake of dietary fiber, especially cereal fiber, may help prevent gain in body weight and waist circumference.
· However, these findings do not exclude the possibility that fruit and vegetables protect against weight gain through other factors, such as reduced dietary energy density and/or reduced total fat intake.
· The investigators also suggest that the effect of fiber on weight change may be of public health significance, although individual effects were small.
· A weight change of 39 g/year (for 10 g/day of fiber intake) represents approximately one third of the mean weight change in this study population (115 g/year).
· Assuming that the average absolute real annual weight gain is 400 g, a 10-g/day increase in total dietary fiber intake would prevent approximately 10% of weight gain.
· Limitations of the study include among-center differences in methodologies used to collect anthropometric data at follow-up.
· Dietary intake was evaluated once at baseline. The concurrent association between changes in fiber intake and changes in weight and waist circumference therefore could not be determined.
Clinical Implications
· In a large, prospective, European cohort, total fiber intake was inversely associated with subsequent change in weight and waist circumference. The effect of fiber on weight change may be of public health significance, although individual effects were small.
· The association was largest for cereal fiber intake. Fruit and vegetable fiber was not associated with weight change. 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. (Maart 2010)
