The FDA is coming down hard on diet pills in the the most popular month for weight loss. The agency  has more than doubled its list of dangerous diet products, warning consumers not to ingest them. The agency is also seeking recalls. The FDA says some of the products contain unlisted ingredients.

One is rimonabant, which the agency is not approved for marketing in the United States. In October 2008, Sanofi-aventis, which legally sells rimonaban in Europe under the brand name Acomplia agreed to stop marketing the product. The FDA has identified another unlisted diet pill ingredient, phenolphthalein, a suspected cancer-causing agent. The health risks of some ingredients include seizures, strokes and heart attacks, the FDA says.

The makers and sellers of the 69 products are at risk, first with regulators for not disclosing the ingredients and second with consumers who may fall ill. There is also a threat to makers of wholesome diet products. The FDA says that some of the targeted products are advertised with words such as "natural" and "herbal."

Agency action places a cloud over all dietary supplement companies by casting suspicion on labels, products and manufacturers. Firms that produce and sell untainted products may become targets of fast-spreading, erroneous rumors. The best responses: Put a message all over your Web site; tell your customers, retailers and distributors that your products are safe; and prepare for the calls and e-mails.