Improve your cholesterol with oats – and without

Oats contain a soluble fiber known as beta-glucan, which is the substance believed to be primarily responsible for oats' cholesterol-lowering effects. Currently the United States Food and Drug Administration allows products containing a minimum specific amount of oat bran or rolled oats to bear labeling similar to that found on oatmeal: "3g of soluble fiber daily from oatmeal, in a diet low in saturated fat and cholesterol, may reduce the risk of heart disease."

Researchers in Australia decided to compare two levels of beta-glucan intake to see if an even lower level of daily intake might have the same cholesterol-lowering effects (Brit J Nutr 2012;107(7):1037-1047). They recruited 87 middle-aged men and women who were overweight and had mildly increased cholesterol levels but were otherwise healthy. For six weeks all of the participants followed a reduced-fat and low-saturated-fat diet that was designed to maintain their current weight. In addition, they were provided with breakfast cereals and snack bars that they were required to eat daily.

What the participants did not know was that they had been randomly assigned to one of three test groups. One group's breakfast cereal and snack bars did not contain any oat products (the control group). A second group's breakfast cereal and snack bars provided a total of 3.2 grams of beta-glucan per day (this was known as the "high oat" group), and the third group's cereal and snack bars provided 1.5 grams of beta-glucan per day (the "low oat" group).

The participants' cholesterol levels, along with their glucose and insulin levels, were tested at the start of the study, after three weeks, and again at the end of the six-week study.

The researchers had expected to find that those whose diets were supplemented with the oat products had improved their cholesterol scores more than those in the control group. However, to their surprise all of the participants improved their cholesterol scores. Even more surprising was that while those in the control group improved their LDL cholesterol by about 5.5%, those in the oat groups improved their LDL cholesterol only slightly more - about 8.5%.

What this means for you

There are really two conclusions here. Certainly this study suggests that the amount of beta-glucan required to affect cholesterol scores is less than we had previously thought. The more important conclusion, however, is that improving your diet by reducing saturated fat and eating higher quality calories can have significant effects on your cholesterol - with or without oatmeal.

First posted: April 11, 2012