If there is a box of oat bran languishing in your cupboard, it could be time to dust it off and knock it open. A new analysis of 28 randomized controlled trials shows that oat fiber significantly lowers LDL (“bad”) cholesterol and total cholesterol in healthy individuals and in people with diabetes. Published this month in the American Journal of Clinical Nutrition, the analysis examined data from studies that gave 3 to 12.4 grams per day of oat beta-glucan (OBG), mostly in the form of oat bran, to participants for 2 to 12 weeks. OBG is the main soluble fiber in oats, and is the primary active component linked to oat’s cholesterol-lowering effects. Here’s what the analysis uncovered:
Compared to the control groups, those receiving OBG had significantly lower LDL (“bad”) cholesterol and total cholesterol.
Compared to healthy individuals, people with type 2 diabetes and those with higher baseline LDL cholesterol had significantly greater reductions of LDL cholesterol when consuming OBG. Nevertheless, the study data was not strong enough to draw a firm conclusion on this point.
OBG did not affect HDL (“good”) cholesterol or triglycerides.
OBG lowered cholesterol regardless of the dose or duration of the trial.
While the results are consistent with other findings on OBG and cholesterol, the new research is among the first to pool data from studies that looked at daily doses of OBG equal to or greater than 3 grams. One of the principal reasons for investigating this dosage level is that many health organizations recommend consuming OBG in amounts equal to or greater than 3 grams. However, the researchers found it curious that the effects of OBG were not linked to dose or duration. The likely explanation, as far as dose goes, is that there is a threshold above which increasing the dose of OBG does not produce any additional effect. That threshold is likely below 3 grams per day. Since the new analysis only looked at 3 or more grams per day, it did not find a dose-response relationship
Source: American Journal of Clinical Nutrition