Background: Evidence from epidemiological studies suggests that higher whole grain intake is associated with improvements in body weight measures. Evidence from randomized controlled intervention studies is controversial.
Objective: To assess the scientific evidence, using a descriptive systematic approach, related to the relationship/effects of whole grain on weight management.
Methods: Medicine Medical Subject Headings (MeSH) were used to search in Medline and Scopus, dating from 1980 to July 2013. Subsequently, 2 researchers assessed independently the resulting abstracts, using hierarchically targeted selection criteria.
Results: A moderate body of evidence from epidemiological studies consistently demonstrates that a higher intake of whole grains is associated with lower body weight, BMI, waist circumference, abdominal adiposity, and weight gain. The evidence from intervention studies is, in comparison, limited and less consistent. Current evidence fails to clearly demonstrate that whole grain intake can contribute to weight loss independent of hypocaloric diets. The lack of consistency in intervention studies may partly be explained by heterogeneity in study duration, types and amounts of whole grain foods included, population, and sample sizes.
Conclusions: Future epidemiological and intervention studies are needed to address the limitations observed in the current body of evidence, importantly using a consistent definition of whole grain foods, and the amount of whole grains consumed. Furthermore, studies need to be conducted on diets that potentially include single grains.