A 57-year-old loophole in the law has allowed food manufacturers to add nearly 1,000 ingredients into foods without consulting the Food and Drug Administration about their safety, according to a new investigation by the Center for Public Integrity (CPI).

"That means people are consuming foods with added flavors, preservatives and other ingredients that are not at all reviewed by regulators for immediate dangers or long-term health effects," wrote CPI.

The heart of the problems lies in the food industry's ability to essentially regulate itself by determining on its own which additives are safe.

Take lupin, for example, a legume from the same family as peanuts. It's considered a major food allergen in Europe and must be labeled as such on packaged foods.

The FDA, responsible for regulating 80 percent of the country's food supply, has known about lupin's potential adverse health effects since at least 2008, and previously told one Australian-based food company that simply listing lupin on ingredient labels would not be a sufficient enough warning, as the ingredient "failed to meet the standards for general recognition of safety." The company eventually withdrew its application and decided not to sell the additives in the U.S.

But per the loophole, companies are still not legally required to identify lupin as an allergen on products sold in the U.S.

It can be found on the ingredient list of products in supermarkets around the nation in the form of lupin flour, lupin protein, and lupin fiber, but many people have no idea of its potentially life-threatening side effects.

This is because manufacturers are able to "deem an additive to be 'generally recognized as safe' - or GRAS - without the agency's blessing, or even its knowledge," CPI reported.

To deem a food as GRAS, a company is supposed to establish that the additive is commonly considered safe by scientific experts, but as CPI notes, "some ingredients defy consensus, as consumers, scientific groups and sometimes even the FDA have pointed out."

Regardless, companies often declare ingredients safe without reporting the results of critical toxicity tests, according to researchers.

Just as alarming is the fact that food safety decisions are "often made by a small group of scientific experts repeatedly hired by companies or consultants with a financial incentive to market new ingredients," CPI found. "Several of these scientists previously served as scientific consultants for tobacco companies during the 1980s and 1990s, when the tobacco industry fought vigorously to defend its products."

Michael Taylor, the FDA's deputy commissioner for foods, told the Washington Post last year, "We simply do not have the information to vouch for the safety of many of these chemicals."

Industry scientists and lawyers scoff at the idea of reforming the GRAS loophole to increase government oversight, saying such reforms could stall innovation, cripple the FDA and result in additives taking years to get approval.

Other popular GRAS additives include trans fats, which have been linked to heart disease, stroke and Type 1 diabetes; methyl eugenol, which displayed carcinogenic activity in rats; carrageenan; mycoprotein; and some green tea extracts.