by J. Raloff
Last week, the Food and Drug Administration announced that makers of low-fat, oat-rich cereals and other foods will be permitted to tout the ability of their products to lower serum cholesterol, a risk factor for heart disease.
Previously, the agency had allowed health claims for individual food components, such as calcium, or for natural food classes, such as "fruits and vegetables." The new ruling marks the first federally sanctioned health claim for a manufactured food.
In the gut, oat's soluble fiber -- beta-glucan -- forms a viscous gel that surrounds cholesterol-rich bile acids, limiting their reabsorption by the blood. The liver responds by making more bile acids and pulling more cholesterol from the blood. This explanation of oats' cholesterol-lowering ability, which has been documented in many studies (SN: 5/26/90, p. 330), spurred the Chicago-based Quaker Oats Co. to petition for the new health claim.
Yet even Quaker was surprised by the scope of FDA's ruling. Though studies by the company and others showed that foods rich in oats or oat bran can lower cholesterol -- even in people on a low-fat diet -- oat flour's ability to do that remains unproved, says Steven L. Ink, Quaker's nutrition director.
Because "we didn't have any data to specifically address the question," he says, FDA indicated last fall that it would not allow the health claim on products made with whole-oat flour. Yet when the ruling emerged last week, oat flour products, such as Cheerios by General Mills in Minneapolis, were included -- apparently, Ink points out, in response to unpublished data submitted to the agency by researchers at the University of Minnesota some 8 months after the formal comment period. Ink says that Quaker will work to confirm oat flour's anticipated effects -- "to make sure that all we've done thus far is not undermined by a question that was not thoroughly addressed."
In fact, data from David Jenkins of the University of Toronto have shown that beta-glucans are not all equal. Each fiber consists of a long chain of identical units; both the length of the chain and the number of cross-links it contains contribute to its viscosity -- and to its biological effects. Because milling into flour, cooking, pressure extrusion, and other food-processing techniques may shorten the chain, Jenkins says he encouraged FDA to endorse health claims "only for materials shown to be effective."
Jur Strobos, a Washington, D.C.-based consultant and former policy director at FDA, believes "the health claim system will rise or fall on the success of this particular health claim." If consumers believe it and eat accordingly, he expects the next petition to seek a health claim for soy protein, "which also has a strong cholesterol-lowering effect."