Effect of n-3 fatty acids supplementation during life style modification in women with overweight.

OBJECTIVE: The marine n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) exert numerous beneficial effects on health, but their potency to defend against development of peripheral insulin resistance of healthy person with overweight remains poorly characterized. We aimed to evaluate the effect of a combination intervention using EPA + DHA and the lifestyle modification (LSM) in women with overweight. METHOD: In a parallel-group, three-arm, randomized trial (UMIN Clinical Trials Registry - R000031131), 34 women were assigned to a 12-week-intervention using corn oil (1.5 g/day; placebo); LSM and corn oil (1.5 g/day; LSM); or LSM and EPA + DHA concentrate (1.5 g/day, containing ~ 0.6 g EPA + DHA; LSM & n-3). At baseline and after intervention, anthropometric measurements including bioelectrical impedance analysis, spiroergometry, 24-hours dietary recall, and various metabolic markers, adiponectin and cytokines were evaluated in serum using standard procedures. Data from 29 women were used for the final evaluation. Wilcoxon two-sided rank-sum test was used to inspect the differences between LSM and LSM & n-3, and placebo groups, with a p-value of ≤ 0.05. All computations were performed with MATLAB Statistics Toolbox. RESULTS: In comparison with placebo, LSM and LSM & n-3 decreased body weight, waist circumference, and body fat, and increased VO2max/kg. LSM & n-3 increased adiponectin levels in comparison to LSM. Fasting insulin, IL8, and cholesterol were decreased by LSM, but were unchanged by LSM & n-3. IL6 was not affected in LSM & n-3, while it was increased in LSM. Other inflammatory markers, as well as leptin, LIF, follistatin, BDNF, and fasting triacylglycerol were not significantly affected by any of the interventions. CONCLUSION: Besides preventing a modest negative effect of LSM on IL6 and adiponectin level, the combination of LSM and EPA + DHA supplementation could be probably used to improve the functional capacity of adipose tissue in women with overweight.

Chromium Supplementation Reduces Resting Heart Rate in Patients with Metabolic Syndrome and Impaired Glucose Tolerance.

Chromium (Cr) is considered as an important mineral, involved in biochemical reactions in human metabolic pathways. Organically bound Cr supplementation has been suggested to improve glycemia especially in patients with type 2 diabetes mellitus, but there are conflicting reports on efficacy. Effect of Cr is not clear in prediabetes status. Seventy patients with metabolic syndrome and impaired glucose tolerance (IGT), who are observed and treated in the Center of Preventive Cardiology of the University Hospital in Pilsen, were included in the prospective, randomized, double-blind, and placebo-controlled clinical study. Effect of Cr-enriched yeast (200 µg of elementary Cr in the morning and 100 µg in the evening) on glucose, lipid metabolism, fat tissue hormones, oxidative stress, and DNA damage markers was analyzed. There were no significant changes in glucose and lipid parameters, oxidative stress, or other laboratory markers. Only resting heart rate was significantly reduced in patients treated by Cr yeast, reflecting reduced sympathetic activity. This could represent an important cardiovascular risk reduction in patients with high cardiometabolic risk.

Effect of chromium-enriched yeast on fasting plasma glucose, glycated haemoglobin and serum lipid levels in patients with type 2 diabetes mellitus treated with insulin.

Chromium is required for a normal insulin function, and low levels have been linked with insulin resistance. The aim of this study was to follow the effect of chromium supplementation on fasting plasma glucose (FPG), glycated haemoglobin (HbA1c) and serum lipids in patients with type 2 diabetes mellitus (DM2) on insulin therapy. Eleven randomly selected patients with DM2 on insulin therapy were supplemented with a daily dose of 100 µg chromium yeast for the first supplementation period of 2 weeks. In the second supplementation period, the chromium dose was doubled and continued for the next 6 weeks. The third phase was a 6-week washout period. After each period, the levels of FPG and HbA1c were compared with the corresponding values at the end of the previous period. Serum triglycerides, total HDL and LDL cholesterol values after supplementation were compared with the baseline values. FPG decreased significantly after the first period of chromium supplementation (p < 0.001), and a tendency to a further reduction was observed after the second supplementation period. Similarly, HbA1c decreased significantly in both periods (p < 0.02 and p < 0.002, respectively). Eight weeks after withdrawal of chromium supplementation, both FPG and HbA1c levels returned to their pre-intervention values. The serum lipid concentrations were not significantly influenced by chromium supplementation. Chromium supplementation could be beneficial in patients with DM2 treated with insulin, most likely due to lowered insulin resistance leading to improved glucose tolerance. This finding needs to be confirmed in a larger study.