Almost everyone believes that lowering salt in the diet can lower a person’s blood pressure, but despite that belief and decades of warnings from government agencies, health organizations, and our doctors, Americans still eat about 1,000 mg of sodium a day more than the recommended limit of 2,300 mg. So this summer the U.S. Food and Drug Administration responded by unveiling “guidance” for how the food industry could lower sodium in their products over the next decade. As well-intentioned as the plan might be, it has many problems.
First, the mission of the FDA is supposed to be protecting consumers from dangers in the food supply - not protecting us from our own choices.
Second, while the FDA call them “voluntary guidelines,” the reality is that manufacturers will be under immense pressure to comply. After all, the agency that is the gatekeeper, and possibly the single biggest impediment, between their products and the market.
Most importantly, the FDA plan—even if it successfully reduced sodium in the food supply—is unlikely to result in a healthier population. In the meantime, the focus on salt overshadows better approaches to lowering blood pressure and improving health.
Evidence shows that most human beings consume salt within a relatively narrow range and that our sodium intake has remained more or less stable for at least the last fifty years. That’s pretty amazing considering how much more processed (and heavily salted) foods we consume today compared with previous generations. When you consider our proven inability to reduce our own sodium intake, despite constant warnings, and the worldwide consistency in sodium intake, despite cultural differences, that’s a strong indicator that we don’t merely decide to eat more or less salt. Rather, we are unconsciously and physiologically driven to eat a certain amount of sodium. This means that even if the FDA succeeds in lowering salt in the food supply, people will probably just add it back into their food or add in other salty foods to their diet.
But, let’s say the FDA plan works and we all end up eating less salt. It’s unclear that this would result in better health for the majority of people. While most of us accept the idea that lowering salt in the diet will lower blood pressure, the actual scientific research shows that only a small percentage of the population—an estimated 17 percent—are “salt sensitive” or will see blood pressure rise with increased dietary sodium. For everyone else, even significant sodium reduction will have no measurable effect on blood pressure.
You might be thinking: well, it can’t hurt to cut out some salt…right? The troubling answer is: that’s not clear, either. Emerging evidence suggests that populations with diets that have lower-than-average sodium are at a higher risk for worse health outcomes (as are those with higher-than-average sodium levels). Why might groups with lower sodium in their diet be more likely to die? Unknown. But we must demand that regulators proceed with serious caution before making blanket recommendations regarding salt or trying to push the entire population toward behavioral changes that have unknown risks.
Perhaps worst of all, the FDA’s sodium reduction plan, with all its accompanying hype, reinforces the idea that salt is the be-all, end-all of hypertension prevention. While salt restriction can certainly be an effective way for some people to lower their blood pressure, for most people it will have no effect. On the other hand, there is strong evidence that losing weight or increasing potassium in the diet are just as effective at lowering blood pressure as moderate salt restriction. In addition to being effective, these approaches to hypertension risk reduction might be easier for people to adhere to, especially for those who find salt restriction difficult. Unfortunately, while most people know that eating more fruits and vegetables would be good, few realize that doing so might lower their risk of hypertension, heart attack, and strokes. This ignorance is, in part, due to the government’s continued myopic focus on salt. Rather than perpetuating public health policy that has failed for nearly forty years, we urged the FDA to focus instead on protecting the food supply from real threats and to allow the appropriate health agencies and physicians to advise the people on nutrition that makes our lives longer and healthier.