Investigation of the impact of blueberries on metabolic factors influencing health

•Blueberries consumed on a daily basis have been shown to significantly reduce weight loss and body fat levels in humans.•Blueberry phenolics and antioxidants have been found to have remarkably high bioaccessibility values.•Blueberries are associated with a 2 times more reduction of insulin resistance which reduces the risk of diabetes.•The biggest health beneficial contribution of blueberries has been determined to be the lowering of LDL cholesterol. In this study, ingestion of blueberry fruit by overweight and obese individuals, who were participating in medical nutrition therapy, was investigated. The study was designed to determine the impact on body weight and metabolism (glucose, HbA1c, TSH, total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, ALT, AST, uric acid, insulin, insulin resistance, hemoglobin) of obese patients over a 12week period of time. Clients were selected based upon their participation in the clinical study as well as measurements which included: body weight, fat, fluid, muscle ratio, and biochemical parameters. The study was conducted with 54 adults (blueberry n=27 and control n=27). Midway through the study, the clients in the blueberry group replaced 50g of carbohydrates with a 50g serving of blueberries. Blueberry fruit is one of the important antioxidant resources due to the content of anthocyanins and phenolic substances. While positive changes were observed in all values in both groups, significant differences in the intervention group were observed in BMI, insulin levels, insulin resistance, LDL, total cholesterol, and uric acid levels. Those differences were observed between baseline and 12th week values. In the 12th week, weight loss (kg) and body fat reduction (%), in the blueberry group was determined to be 11–14% more in males and 3–1.4% more in females, from the control group. Total cholesterol was changed at the beginning 187.29±34.36mg/dL; 203.19±41.10mg/dL for control and for blueberry group. At end of the trial, values had changed between 178.59±29.42mg/dL; 173.20±33.26mg/dL for control and blueberry groups respectively. LDL and total cholesterol (18.3–14.75%) values were found statistically significant at the end of 12weeks in the group which added blueberries to replace carbohydrates.