The salt controversy

Is eating too much salt really harmful? Traditional medical advice and routine doctor visits may have convinced you that’s a definite “yes,” but the science is anything but uniform. So why isn’t this reflected in routine clinical practice?

The salt controversy does more than raise questions about how much salt is too much; it points to the very heart of a little-discussed problem: that much of the medical information we receive is not based on scientific consensus, despite the definitive and certain tone of the statements made by key voices, including our doctors .

We’ve all been told that we tend to eat “too much” salt and that too much salt is bad. Doctors, dieticians and health associations have long warned that excessive sodium consumption can impair kidney function, raise blood pressure, increase the risk of cardiovascular disease and even impair sleep quality.

Recognizing that, for most people, processed foods are a major source of sodium, the U.S. Food and Drug Administration (FDA) announced in October 2021 a new plan to encourage packaged food manufacturers to reduce sodium. added salt in their products. The FDA has set a new average salt intake goal of 3,000 milligrams per day, down 12% from the US average of about 3,400 milligrams per day.

However, the Dietary Guidelines for Americans, produced by the US Department of Health and Human Services and the US Department of Agriculture, recommend that adults limit their sodium intake even further, to less than 2,300 milligrams per day. or about 1 teaspoon of table salt.

New animal research reveals that excess salt can affect the mind as well as the body. According to some studies, too much salt can increase stress levels, thereby affecting behavior (at least in mice).

New search

One such recent study, carried out at the University of Edinburgh in Scotland and published this month in the journal Cardiovascular Research, found that, in mice, eating too much salt increased stress hormones in the body.

Researchers found that a high-salt diet increased levels of the stress hormone glucocorticoid by 75%. Moreover, not only did resting stress hormone levels increase in the mice, but their hormonal response to environmental stress was also double that of mice that ate a normal diet.

“We know that eating too much salt damages our heart, blood vessels and kidneys. This study now tells us that high salt in our foods also changes how our brains handle stress,” said study co-author Matthew A. Bailey, professor of kidney physiology at the Center for Cardiovascular Sciences from the University of Edinburgh, in a statement.

An article published this year in the journal Neuroscience & Biobehavioral Reviews reviewed a number of studies to quantify what is known about the effects of salt on animal behavior.

The review authors, from Kent State University in Kent, Ohio, wrote that although excessive salt intake is a well-known risk factor for cardiovascular disease, so far “relatively little has been explored about how it affects behavior, despite the ubiquity of salt in modern diets.

The research tested behavioral changes such as anxiety and aggression in mice fed a high-salt diet. Excessive salt intake in adult animals has been found to affect their spatial memory and their “fear expression”. High salt intake in early life has been shown to increase their locomotion and impede social and spatial behavior.

The study authors wrote that these results show that “close study of the effects of salt will likely uncover broader behavioral implications.”

Is salt really that bad?

James DiNicolantonio, Doctor of Pharmacy, opposes what he calls the “salt deficiency dogma” and believes that salt has been unfairly demonized.

He claims that our bodies push us to consume around 3,000 milligrams to 4,000 milligrams of sodium per day in order to stay in homeostasis, “an optimal state in which you put the least amount of stress on the body.”

DiNicolantonio told The Epoch Times that of the salt intake studies done on humans, each “has an inherent flaw.”

“Nearly all the studies don’t give exactly the same diet, the only difference being the level of salt intake,” he said. “In general, what [researchers] do is that they give more fruits and vegetables, [a diet] which happens to be lower in salt, and then they sort of extrapolate the benefits…and you can’t necessarily extrapolate that.

In his book “The Salt Fix: Why Experts Got It All Wrong and How Eating More Might Save Your Life,” DiNicolantonio, who is a cardiovascular research scientist at St. Luke’s Mid America Heart Institute in Kansas City, Missouri, argued that the great majority of us don’t need to watch our salt intake. He believes salt restriction is harmful and that too little salt can make us crave sugar, leading to weight gain and type 2 diabetes.

In fact, low-salt diets may have created America’s high blood pressure epidemic, DiNicolantonio wrote. In South Korea and other parts of the world, people regularly consume more than 4,000 milligrams of salt a day and yet have very low rates of heart disease and high blood pressure.

For most people, says DiNicolantonio, eating more salt can improve energy, sleep, fitness, and even fertility and sexual function. He argued that “until the dogma of low salt is successfully challenged, we will be stuck in this same perpetual loop that keeps our bodies starved of salt, addicted to sugar and ultimately deficient in many nutrients. essential”.

For animals, he pointed out, “there are no dietary guidelines, of course – no medical guidelines to create a conscious effort to limit salt intake.” Except for those with certain medical conditions, DiNicolantonio said we don’t have to worry about “overloading salt” because our bodies handle any excess. A low-salt diet “indicates a crisis for the body, not a recipe for optimal health,” he writes.

An ongoing controversy

Researchers from Columbia University and Boston University in 2016 conducted a “meta-knowledge analysis” of what they called “the salt controversy.” The analysis, published in the International Journal of Epidemiology, looked at 269 reports published between 1978 and 2014 that examined the effects of sodium intake on cerebrovascular disease or mortality.

Researchers found that 54% of reports supported the hypothesis that reducing dietary salt leads to population health benefits. A third (33 percent) did not support this hypothesis, and 13 percent were inconclusive.

So while scientists have long disagreed about the benefits of reducing salt intake, public health messages about salt don’t appear to reflect that uncertainty, the researchers noted.

“The gap between the uncertainty in the scientific literature about the potential benefits of salt reduction in populations and the certainty expressed by decision makers involved in developing public health policy in this area is shocking,” they said. writing.

“Assuming that all parties involved have the best interests of science and public health in mind, this controversy raises questions about the production of population health science knowledge and how that production influences public health practices.”

The researchers found that the authors of the report were 50% more likely to cite articles that reflected their point of view, whether or not they thought salt reduction was beneficial. Moreover, only a few prolific researchers produced most of the work in the field and seemed unaffected by the work of researchers who came to different conclusions.

“We found that the published literature bears little imprint of an ongoing controversy but rather contains two almost distinct and disparate lines of research, one supporting and the other contradicting the hypothesis that salt reduction in populations will improve clinical outcomes,” the authors wrote.

Public health officials, it seems, may have chosen to amplify the findings of just one part of all the research produced on this topic, rather than acknowledge that there is a long two “sides” in the salt controversy.

Practical advice

DiNicolantonio offered practical advice for those concerned about salt intake.

“If you’re someone who eats a whole diet of mostly whole, nutritious foods – meat, vegetables, fruit – you’re going to be consuming a very low amount of salt and you’ll probably have to add some back in to bring you back down to a normal intake,” he said.

“While if you’re someone who eats mostly processed foods…you’re probably getting enough salt already,” he said.

“Salt is an essential mineral. There will be an amount that will not be enough, like any mineral. There will be an amount that will be too much, like any mineral, and there will be an optimal intake. The optimal intake seems to be a normal salt intake. So not high, not low, but allowing your body to consume the salt it naturally craves, which is basically how we deal with water cravings.