Effects of brown and golden flaxseed on the lipid profile, glycemia, inflammatory biomarkers, blood pressure and body composition in overweight adolescents.

Background: Flaxseed is a promising alternative to reduce the risk of diseases associated with body weight excess because it is rich in a-linolenic acid, lignans, and dietary fiber. Flaxseed (Linum usitatissimum) can be found in brown and golden varieties; however, questions have arisen as to whether the variety may influence the health effects.

Objective: The objective of this study was to compare the effects of brown and golden flaxseeds on lipid profile, glycemia, blood pressure, inflammatory status,body weight, and body composition in overweight adolescents.

Methods: Seventy-five overweight adolescents (33 boys, 42 girls; age 13.7 ! 2.1 y), from Alegre-ES, Brazil, were randomized to one of the three groups (n ¼ 25) on a parallel, single-blind clinical trial. They received 28 g/d of brown flaxseed (BF), golden flaxseed (GF), or the equivalent amount of wheat bran (Control, CG) in different preparations at school from Monday to Friday for 11 wk. Blood pressure, anthropometric evaluation, and the analyses of blood total cholesterol, lipoproteins, glucose, and inflammatory markers were performed at the beginning and at the end of the intervention. The data were analyzed by ANCOVA at 5% significance.

Results: The groups who consumed brown and golden flaxseed showed significant reduction in diastolic blood pressure. Brown and golden flaxseed did not differentially affect plasma lipid responses, plasma glucose and inflammatory profile, although all groups (BF, GF, and CG) showed increased levels of TNF-a.

Conclusions: The adolescents consumed about half the daily amount provided, which may not have been sufficient to exert the health benefits of flaxseed reported in the literature, concerning the lipid profile, inflammation biomarkers and body composition.