Study Investigates Health Benefits of Barley

By Jim Core
May 29, 2003

Diets high in barley were found to lower total cholesterol levels, according to early results from a long-term Agricultural Research Service study. At the ARS Diet and Human Performance Laboratory in Beltsville, Md., research chemist Kay Behall is studying how eating foods prepared with grains such as barley and oats might reduce risk factors associated with excess weight, type 2 diabetes mellitus and cardiovascular disease.

Eating barley-containing foods improved several cardiovascular risk factors. For example, in a study of male participants, researchers found increasing whole grain foods in a healthy diet could reduce high blood pressure.

A diet higher in soluble fiber also had the greatest effect on reducing total and low-density lipoprotein (LDL) cholesterol levels--the bad cholesterol. Levels of high-density lipoprotein (HDL)--the good cholesterol--either increased or did not change, resulting in an improved total LDL/HDL ratio. Early findings from a female study found results were more pronounced in post-menopausal women than pre-menopausal women.

Significant reductions in blood pressure have previously been reported in other high-fiber grain diet studies. It is known that soluble fiber found in oats can reduce cholesterol. Since barley contains similar fiber, the researchers decided to examine its impact in a healthy diet.

At the Diet and Human Performance Laboratory, part of ARS' Beltsville Human Nutrition Research Center, Behall and a recently retired colleague, Judith Hallfrisch, conducted several studies to see if eating a diet high in soluble fiber promotes glucose or hormone changes, resulting in reduced insulin resistance. Insulin resistance is a diminished sensitivity in body tissues to the action of insulin, which is to bring glucose into those tissues as a source of energy. When the human body has increased insulin resistance, the pancreas may try to compensate by secreting more insulin, which, over time, may exhaust the pancreas' ability to produce insulin.

The ARS scientists have been investigating whether eating barley and oats can reduce the body's glycemic response (a measure of a food's ability to elevate blood sugar) and hyperinsulinemia (when the body produces too much insulin in response to a meal), independent of weight loss. In other words, they want to see if the grains will have a positive effect on health, even if people are not losing weight.

ARS is the U.S. Department of Agriculture's chief scientific research agency.

Read more about this research in the May issue of Agricultural Research magazine.