Consumption of yacon flour improves body composition and intestinal function in overweight adults: A randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND & AIMS: Yacon root is a natural source of fructooligosaccharides (FOS), and it has been studied for its potential effect as a functional food. However, FOS in the in natura root are rapidly hydrolyzed. Thus, the use of dehydrated products such as flour ensures stability of FOS. The effect of chronic consumption of yacon flour on body composition, food intake and of biochemical variables concentration has not yet been evaluated in humans. Thus, we evaluated the effects of yacon flour consumption on these variables associated with excess body weight. METHODS: Twenty-six adults (31.3 ± 8.5 years) with excess weight (30.4 ± 2.4 kg/m2, 40.16 ± 6.7% body fat) participated in this randomized, double-blind, six-week study. Subjects were randomly allocated to one of the experimental groups (control (n = 13) or yacon flour (n = 13)), received the prescription of energy-restricted diets (- 500 kcal/day) and daily consumed a breakfast drink not containing or containing 25 g of yacon flour (0.1 g of FOS/kg body weight). At the beginning and at the end of the study, biochemical analyses (glycemia, insulinemia, lipid profile and liver function markers), anthropometrics (weight, waist, hip and neck circumference and sagittal abdominal diameter), body composition (lean mass, total body fat, trunk fat, android fat and gynoid fat), blood pressure, intestinal function, and food intake were assessed. RESULTS: Daily yacon flour consumption was well tolerated, did not cause adverse gastrointestinal effects, increased dietary fiber consumption, promoted greater body weight, waist circumference, waist to height index, sagittal abdominal diameter, and body fat reduction, besides improving bowel function in comparison to the control group. CONCLUSIONS: Yacon flour served as a natural fiber supplement and proved to be an effective adjuvant to be used in nutritional strategies to control excess body weight.

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 » 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.