CASE STUDY: BENECOL MARGARINE.

Active Ingredient: Stanol esters, which are extracted from pine tree pulp.

The Promise: Benecol lowers cholesterol.

Does It Work? In a well-designed study sponsored by the Finnish company that developed the margarine, 102 people with mildly elevated cholesterol (235 or higher) who ate three pats of Benecol every day for a year lowered their cholesterol by an average of ten percent.(1) Cholesterol didn't fall in 51 people who were given a similar margarine without stanol esters.

The Controversy: Last December, Benecol's U.S. distributor, McNeil Consumer Products (a division of Johnson & Johnson) said that it planned to market the margarine as a dietary supplement. That way, it could avoid having to ask the Food and Drug Administration (FDA) to approve the cholesterol-lowering stanol esters as a food additive. Additives must undergo extensive safety tests before they can be used. McNeil wanted Benecol to hit store shelves before a rival product, Take Charge--a cholesterol-lowering margarine manufactured by Unilever's Lipton division that uses a stanol-like ingredient extracted from soybeans.

Not so fast, said the FDA. Benecol is a food, not a supplement. In late January, McNeil arranged with the FDA to declare that stanol esters are a "Generally Recognized As Safe" food ingredient. That would let Benecol be marketed as a food without having to do food-additive testing on the esters.

So far, the FDA hasn't gone after other foods that call themselves supplements--Hain Kitchen Prescription Soups, for example. They all appear to be illegal. According to the Dietary Supplement Health and Education Act (DSHEA), a supplement cannot be "represented for use as a conventional food...."

Is It Safe? The company's studies were far too small to tell. For example, if Benecol caused some harm to one out of every 100 people, the research wouldn't have picked it up. And the studies didn't look at what happens to people who use more than three pats a day, either because they think more will lower their cholesterol further or because they run out of other margarine.

The Bottom Line: Benecol appears to lower cholesterol levels. And despite the unanswered safety questions, it has been far better tested than the vast majority of functional foods.

(1) N. Eng. J. Med. 333:1308, 1995.