–AMA, AHA, ACC, etc voice support, but not everyone agrees.
After decades of discussion and inaction, the FDA today took a first concrete step toward reducing sodium levels in the general population: It issued draft guidance for voluntary sodium reduction targets for the food industry.
The FDA said that the new recommendations come from “leading experts and the overwhelming body of scientific evidence.” But other experts pointed out flaws in the supporting evidence and said the FDA unfairly dismissed evidence opposing its views.
The FDA wants to lower sodium consumption in the general population by targeting food manufacturers and restaurants. According to the FDA, most of the sodium in the U.S. diet comes from processed and prepared foods. The long-term goal is to gradually lower sodium intake from the average of about 3,400 mg/day to 2,300 mg/day. In the short-term, the FDA aims to reduce sodium intake to 3,000 mg/day.
The FDA said that it was “especially encouraging adoption by food manufacturers whose products make up a significant proportion of national sales in one or more categories and restaurant chains that are national and regional in scope.”
The proposed reductions are based on the clearly-established relationship between sodium intake and blood pressure. Reducing sodium will lead to lower blood pressure levels. An FDA press release said that “researchers have estimated lowering U.S. sodium intake by about 40% over the next decade could save 500,000 lives and nearly $100 billion in healthcare costs.”
The proposed FDA guidelines will be open for comments from stakeholders.
The FDA proposal was accompanied by supporting papers in both JAMA and the New England Journal of Medicine by CDC director Thomas Frieden and statements of support from the American Heart Association, the American Medical Association, the American College of Cardiology, and others.
A Salty Disagreement
But the FDA move did not enjoy universal support. The Salt Institute said that the “government’s war on salt is malpractice.”
“The government’s recommendations are so unnaturally low those consumption levels are unheard of in any country in the world,” it said. It cited three separate Cochrane Collaboration reviews that concluded “that there is insufficient evidence to warrant population-wide salt reduction.”
Michael Alderman, MD, of Albert Einstein College of Medicine in New York City, said the government’s case rests on the assumptions that there is a linear relationship between blood pressure reduction and a reduction in cardiovascular events and that there are no other physiological effects of very low sodium levels. The best current evidence, he said, suggests that an optimum sodium level is between 3 and 5.5 g/day.
“Before you submit 300 million people to an experiment you need to know what you’re doing,” said Alderman.
Another scientist, Andrew Mente, PhD, of McMaster University in Hamilton, Ontario, also expressed concern about the FDA proposal. He was the first author of a recent paper published in the Lancet that reached conclusions strongly different from the FDA. The study found that three out of four people had sodium levels between 3,000 and 6,000 mg a day, and that these levels were not associated with increased risk. “That tells you it should not be necessary to do a major overhaul,” he said.
Some people may be pushed down to suboptimal levels under the new guidelines, said Mente. The Lancet paper recommended that, without better studies, sodium restriction should be reserved for people who already have high blood pressure and who already consume high levels of salt.