Flaxseed Reduces Total and LDL Cholesterol Concentrations in Native American Postmenopausal Women.

Key Findings:

Dietary recommendations have for decades identified that a reduction in fat intake is necessary to lower risk of coronary heart disease (CHD). Research has moved to the findings that it is the type of fat, but not total amount of fat, which impacts blood cholesterol levels. Replacing saturated fat with unsaturated fat has been found in epidemiologic studies and controlled clinical trials to more effective in lowering risk of CHD than easting less fat overall. Increased consumption of n-3 fatty acids from fish or plant sources lowers risk of CHD as reported in numerous prospective cohort studies and secondary prevention trials. More recent national dietary guidelines now focus on different types of fat. Further the authors argue against recommendations for a low-fat diet for weight loss as long-term clinical trials have not supported a relationship between low fat and weight reduction. Further research is required to determine the optimal mixture of different fatty acids in lowering the risk of CHD.

Abstract:

The objective of the study was to investigate the extent to which the daily incorporation of approximately 30 g of flaxseed, a rich source of lignans, omega-3 fatty acids, and fiber, for a period of 3 months into the diet of Native American postmenopausal women positively affects their lipid profiles. Fifty-five mild to moderately hypercholesterolemic (5.1 to 9.8 mmol/L) Native American postmenopausal women were randomly assigned to control (A), flaxseed (B) or flaxseed additional oat bran fiber (C) groups. Overnight fasting venous blood was collected at baseline and at the end of the treatment period to analyze lipid parameters. Dietary flaxseed supplementation lowered total cholesterol and low-density lipoprotein cholesterol (LDL-C) by approximately 7% and 10%, respectively. However, the levels of high-density lipoprotein (HDL) and triglyceride remained unaltered. No changes were observed in other clinical and hematological parameters. The results of the present study indicate that Native American postmenopausal women benefit from regular consumption of flaxseed by reducing their risk of cardiovascular disease as seen from lowered LDL-C and total cholesterol levels. (Author’s abstract)