WHEN HOLLY Anderson began taking "starch blockers"--those concentrated forms of isolated kidney bean protein which manufacturers claim inhibit carbohydrate (and thus calorie) absorption--she assumed the Food and Drug Administration had prior knowledge of the sales.

She stopped taking the pills after two weeks, when she read that the FDA had asked manufacturers to withdraw the product. No matter, she hadn't lost any weight. But, she says, "they should have caught it before [starch blockers] went on the market."

For a long time, the FDA didn't even know the product was being sold. The manufacturers consider their product a food, so they never told the FDA about it. "We've never approved it," says FDA spokesman Bruce Brown, "because no pre-market approval is required for foods."

There is, however, an approval process for drugs, and the FDA officials, according to Brown, contend starch blockers are an unapproved new drug. The FDA "asserts positively that starch blockers are being advertised to alter normal body function," says Brown. "That definitely is a clue to their status as a drug . They believe it might be intended to affect the function of the body, as it is supposed to cut down on carbohydrate absorption." In addition, the FDA questions "both the safety and effectiveness and have concern about reports we have received on adverse side effects. The severity and number of reports has increased" since the July 1 announcement that starch blockers must be removed from the market.

It's all a question of semantics. The Food, Drug and Cosmetic Act says that drugs are, among other things, "articles intended for use in the diagnosis, cure, mitigation, treatment or prevention of disease in man or other animals" and "articles (other than food) intended to affect the structure or any function of the body of man or other animals."

To approve a drug, the FDA must be convinced that the product is not only safe but effective. This process requires experimenters or manufacturers to submit reams of data from both animal and human studies. It involves a lengthy and expensive process.

Food includes "articles used for food or drink for man or other animals, chewing gum, or articles used for components of any such articles." Because the FDA doesn't have to approve foods before they are marketed, it "has no way of knowing when a new food is introduced," says Brown, and many manufacturers of starch blockers believe their product is a food.

Pharmicist Robert Lemon, president of one company which makes several different starch blockers, says his products "nutritionally inhibit the absorption of starch" and compares them to isolated soy protein. Soy protein (often used to simulate meat products) is eaten by people who want to lower their intake of fat, calories and cholesterol, says Lemon. "The only difference is that we use isolated kidney bean protein, rather than soy . . . "

"I suggest that FDA officials read their regulations. If they want to classify this substance as a drug then they better go back and change the law because that's the only way they're going to do it."

Because anyone who wants to begin selling food can do so without FDA approval, says Brown, the possibilities are, in theory, limitless. Speaking about food sales generally, Brown says, "If you chose to make a buck as your number one priority and you are not concerned about the long-term credibility of the firm," you can sell about anything if you call it a food.

"This is precisely the way quacks operate," says Brown, whose FDA-designated specialty is "quackery." "They know that the Food Drug and Cosmetic Act is cumbersome for us to administer. They will manufacture something at high markup and sell it quickly." They sell their product while the FDA builds a case and then "literally disappear," says Brown." However, he cautions, there is no information to suggest that's happening in the case of starch blockers.

"There are only 7,000 of us and there are a lot more food entrepreneurs than that. If nobody tells us the products are out there, we're not going to know until somehow the product or the company comes to our attention," Brown contends. In the case of starch blockers, several people called with complaints of nausea, vomiting and diarrhea; many inquiries came from consumers, doctors and even Capitol Hill, and a mass media campaign created a very visible product.

At least 16 companies filed suit against the FDA on July 9 in reaction to the FDA's written order to more than 200 companies that they withdraw their products from the market and submit experiment data and specific information about the contents.

"Clearly our concern is that we've seen no tests. We are getting complaints. We want the world to know that we've not approved the product," says Brown. "Our position is not adversarial to the product," he continues, and although the medical theory supporting starch-blockers is not new, the FDA has seen no evidence as to whether or not they they are effective. "We, like the public at large, stand to benefit if the product works."