This claim has repeatedly appeared in various professional journals, dietary recommendations, and other colorful publications over the past few decades. No dietary advice has ever been so deeply ingrained, prompting millions of people to put away their salt shakers and embark on a low-sodium diet. In reality, however, the relationship between salt and high blood pressure has been controversial from the very beginning. This large-scale anti-salt movement began in 1972, when a published academic article described an experiment conducted on rats. When researchers added a certain amount of salt to the rats' feed, their blood pressure rose. However, the rats used in this experiment were a breed that is extremely sensitive to salt. Moreover, the amount of salt given to these rats, when converted for human consumption, was equivalent to one pound of salt per day! Yet many nutrition and medical professionals were grateful for these experimental results and promoted them to the public.
Another study that had a decisive impact on the salt debate and health policy was the so-called "Intersalt Study" (1988). In this study, medical researchers compared 52 populations from different regions around the world. The results of the evaluation were astonishing: if a relationship had to be found between salt intake and high blood pressure, it was this: as salt intake increased, people's blood pressure actually decreased! In this study, the population with the highest salt intake was residents of Tianjin, China, with an average daily intake of 14 grams. Yet their blood pressure was not higher than that of residents in Chicago, USA, whose average daily intake was only 6 grams.
This should have been the end of the matter. But perhaps losing face is a big deal for scholars, as they continued to spread warnings about salt everywhere. When they ran out of options, they resorted to statistics. Within the framework of the "Intersalt Study" report, they provided data on four ethnic groups. These groups consumed almost no salt, and no increase in blood pressure was found among them. Only by considering these four "exceptions" together could a rather weak link be established between salt intake and blood pressure levels. Because these groups had lifestyles completely different from the average person, and other factors played a significant role in their lives, the results of this study did not attract much interest in the academic community. Nevertheless, it became the guiding principle for health policy throughout the Western world.
By calling on the public to reduce salt intake, preventive medicine experts achieved their goal: high blood pressure is a risk factor for cardiovascular diseases, so more people would turn to them for help. But interestingly, compared to smoking, people are more readily willing to accept advice to reduce salt consumption, even though experiments have proven that quitting smoking brings absolute benefits to the body and helps to continuously improve health. Now, more and more experimental results are being made public, through which it can be learned that reducing salt intake has neither lowered blood pressure in the general population nor extended human lifespan. Only under many restrictive conditions does reducing salt intake have a slight effect on those with high blood pressure.
The myth of "deadly salt" has been debunked. Now scientists are asking the question: "Are the disadvantages of reducing salt intake greater than the benefits?" For example, in the elderly, the advice to abandon salt can put them at risk. It can impair their cognitive abilities and suppress the sensation of thirst, leading to reduced fluid intake in their bodies. Two new studies have shown that restricting salt intake increases mortality and promotes cardiovascular diseases—and the less salt people eat, the higher the risk. It is certain that after reducing salt, the body's cholesterol levels, especially harmful LDL cholesterol, have risen. Many patients who consume less salt and also eat a cholesterol-lowering diet still frequently visit the clinic for various illnesses.
Health policy makers and doctors always try to connect things as simply as possible. As Bill Helene, director of the U.S. Public Health Service's Preventive Medicine Department, said: "People always ask us, 'Is it okay for me to do this or that?' Well, listen up, we can't answer that question until the results of the experiments are in. But the experiments might take five years, and no one is willing to wait that long. People want to know the answer right away... This leads us to be frequently forced to associate with certain viewpoints, and even to represent certain views, even though these viewpoints don't have very scientific reasons." Perhaps for this very reason, we are still burdened with the accusation of excessive salt consumption every day—despite the fact that this accusation goes against science.