Salt is one of the substances placed near the top of modern medicine's blacklist. Before answering your question, it is useful to look at the history of salt so that the issue can be understood properly.

When we examine the history of salt, we learn that wars were fought over salt among various communities. Great civilizations rose by controlling salt production and became wealthy and developed through the salt trade (1). Many ancient settlements, if you notice, are located close to salt deposits.

In ancient Greek culture, captives were reportedly exchanged for salt, and the expression “not worth his salt” is said to come from this practice. Roman soldiers were once paid in salt. In fact, the Latin word “salarium,” associated with salt, is the root of the modern English word “salary.”

In some parts of the world salt was so valuable that European explorers were said to trade a cup of gold dust for a cup of salt during their expeditions. This may sound exaggerated, but in regions where salt was scarce it was considered as valuable as gold and was even called white gold.

The source article states that the Qur'an regards salt, together with the sword and bread, among substances of great sanctity, and attributes to the Prophet Muhammad a saying addressed to Ali recommending beginning and ending a meal with salt and describing salt as a remedy for many ailments.

The preserving quality of salt is also emphasized in the Bible. Jesus is quoted as calling his apostles and followers “the salt of the earth.” The article interprets this metaphor as meaning that, just as salt protects food from spoilage, religious leaders should protect humanity from the sins of the world.

Does salt really raise blood pressure?

Most doctors and the media agree that excessive salt consumption may lead to high blood pressure and therefore contribute to cardiovascular disease.

A positive relationship between dietary salt and high blood pressure was first reported about a century ago in studies conducted by French physicians (2, 3).

Another positive relationship is observed between high blood pressure and cardiovascular mortality. By combining these two relationships, modern medicine tried during the last century to develop the hypothesis that dietary salt could lead to cardiovascular deaths. Let us now examine how accurate these assumptions are.

In the 1970s, Lewis Dahl of Brookhaven National Laboratory showed that salt could cause high blood pressure in rats (4). However, when the study is examined, the sodium load given to the rats, relative to their body weight, is described as equivalent to about 500 grams for a human. The article argues that humans could not tolerate such a load even with high water intake.

Despite this, in 1977 a committee formed by the U.S. Senate recommended that Americans cut their salt consumption by half, based on this research.

The study most relied upon by medical authorities is the INTERSALT study, published in 1988 and involving more than 10,000 people in 52 countries (5). It found a positive, though weak, correlation between dietary salt and high blood pressure. In other words, the study was interpreted as showing that blood pressure rises as salt consumption increases. The article questions how accurately this result should be interpreted.

Medical authorities that accepted the positive relationship reported in INTERSALT, the article says, did not give enough attention to the fact that 48 of the 52 study centers did not show a relationship between salt and high blood pressure. The article notes that this information was present in the published abstract.

The remaining four groups that strongly influenced the overall result—groups with both low dietary salt and generally low blood pressure—were described as traditional communities in countries such as Brazil, Kenya and New Guinea. The article asks whether their lower blood pressure might also be related to less stress, little inactivity or obesity, minimal packaged-food consumption and much greater intake of raw fruit and vegetables rather than salt intake alone.

For INTERSALT to have been more informative, the article argues, comparisons would have needed to control other lifestyle factors. It cites research on an indigenous group living on the San Blas islands of Panama (6), saying that people who previously had little access to salt moved about 50 years earlier to an island where salt intake was higher, yet their blood pressure reportedly remained unchanged.

In summary, the article argues that, contrary to common interpretation, INTERSALT did not establish a relationship between salt consumption and hypertension. It criticizes medical authorities for continuing to present the study otherwise.

A 2004 Cochrane Collaboration analysis of 11 studies is described as finding that long-term salt restriction reduced systolic blood pressure by about 1.1 mmHg and diastolic pressure by about 0.6 mmHg (7), changes the source article characterizes as very small.

The article therefore asks whether it is worth following low-salt diets for such small reductions in blood pressure. It argues that salt restriction may have disadvantages and links it to a range of chronic conditions, including diabetes and cardiovascular disease.

Could you explain some of these harms?

One study is described as showing more myocardial infarctions among hypertensive patients whose salt intake was restricted than among those whose intake was not restricted (8). Another study is cited as finding higher mortality among people with lower salt intake (9). The article argues that such studies are often overlooked.

It also cites a study published in the American Journal of Medicine in 2006, described in the source as following 78 million people for 14 years, and says that cardiovascular mortality was higher among those consuming less salt (10).

The article says that a more recent Cochrane review reported similar findings (11).

This meta-analysis examined controlled studies in which salt restriction lasted more than six months. According to the article, mortality did not differ between salt-restricted and unrestricted groups among either normotensive or hypertensive participants. It adds that mortality was reported to be higher among patients with heart failure who were placed on salt restriction.

A study published two years earlier, in 2011, is also cited as reporting that low salt intake increased mortality from heart disease (12).

Is salt consumption also related to diabetes?

Yes. The article cites a 2010 Harvard study as showing more insulin resistance and diabetes among people with lower salt intake (13).

It also cites a 2011 study in people with type 2 diabetes as reporting higher mortality from both cardiovascular and other causes among those with lower salt intake (14). The article argues that restricting salt could therefore sometimes have the opposite of the intended effect on blood pressure.

Professor, what other harms can salt restriction cause?

The article says researchers have shown that processes related to salt taste, motivation and emotion overlap in the limbic forebrain. It therefore suggests that changes in salt balance may contribute to mood and behavioral disorders and even to the development of Alzheimer's disease.

One study is described as finding that salt-restricted rats stopped engaging in activities they had previously enjoyed (15). The article compares this with anhedonia in depression and suggests that salt may have an antidepressant-like role, speculating that this may help explain why some people strongly crave salt.

The article lists loss of appetite, reduced concentration, attention problems, fatigue, headache, sleep disturbance, feelings of exhaustion, altered taste, thirst, falls and fractures among possible effects of salt deficiency, and says these symptoms are rarely attributed to low salt by clinicians.

Many elderly patients are told not to go outside in hot weather. The article says that if these people are also restricting salt, they may faint and may suffer heart attacks.

In the 2002 Boston Marathon, the article states that 29% of runners developed low sodium (16), which also affected performance. It therefore argues that demanding physical activity requires salt as well as water.

The article also links low salt intake with bone fractures and osteoporosis. It cites a study comparing serum sodium in 364 elderly patients with fractures and the same number without fractures (17): low blood sodium was reportedly present in 4.1% of those without fractures and in more than twice that proportion, 9.1%, among those with fractures.

Traditional communities with high salt consumption

Traditional communities have consumed salt whenever they could obtain it. The article gives the Fala nomads of Tibet as an example of a group consuming especially large amounts of salt. Their diet is described as consisting mainly of milk, cheese, antelope, yak and butter, with almost no fruit or vegetables, but abundant salt. The nomads are said to believe salt keeps them healthy, and the article states that their blood pressure is lower than ours and that they live very long lives (18).

Is the quality of salt important too?

Yes. The article argues that many opinion leaders in human health focus mainly on limiting the quantity of salt but pay much less attention to salt quality, including whether the salt is natural or processed.

Does that mean the refined salt we buy from grocery stores and supermarkets is poor quality? We use refined salt in cooking, but use rock salt when making pickles or brining fish because it is cheaper. Is there a problem with refined salt? Which is better: refined salt or rock salt? Could you explain their characteristics?

Certainly. The article states that 93–94% of global salt production goes directly to industry. It says salt is used in the manufacture of plastics, soda, softeners, detergents, polishes and oils, and that chemical separation processes require sodium chloride (NaCl). The other elements present in natural salt crystals are described as undesirable for certain industrial processes (19).

According to the article, these elements are removed during refining, leaving mainly NaCl. It says that the portion of refined salt not used by industry is directed to the food sector and argues that contaminants may enter the salt during refining. It also raises concerns about the cleanliness of the source area, citing pollution around Tuz Gölü in Türkiye.

The article states that there are major differences between refined and natural salts. It describes refined salt as about 97.5% sodium chloride, with the remaining 2.5% including iodine and anti-caking or moisture-absorbing agents. It names calcium carbonate, magnesium carbonate and aluminium hydroxide among these substances and says they make the salt flow more freely.

It further claims that salt is exposed to temperatures around 650°C during refining and that this changes its chemical structure. The article describes refined salt as consisting of separated crystals and argues that metabolizing it requires additional energy. It also says that excess sodium draws water from cells and associates this process with dehydration and higher blood pressure, stating that 23 grams of water are drawn for every extra gram of sodium.

From a scientific point of view, the article says that natural salt crystals have a distinctive structure. Unlike many other crystals, it describes the atomic structure of salt as electrical rather than molecular and presents this as a factor behind its properties (20).

What minerals does natural salt contain that refined salt does not?

The source article states that natural salt is 84% sodium chloride and that the remaining 16% consists of minerals such as lithium, phosphorus, selenium, magnesium, calcium and vanadium. It further claims that, excluding noble gases, 84 naturally occurring elements are present in natural salt crystals and that the human body likewise contains 84 elements. On that basis, it argues that natural salt supplies mineral needs. It also cites a study from Texas associating lithium-poor water with higher rates of several forms of crime and suicide (21). These are the claims presented in the original article.

Why does refined salt damage our body?

The article argues that the body treats refined salt as an aggressive toxin and tries to eliminate it quickly. It says that processing and excreting excessive salt places a burden on the kidneys and the rest of the excretory system, and it associates refined salt with water retention (edema), heart failure and cellulite.

It further claims that refined salt that cannot be excreted recrystallizes and is stored in joints and bones, and links it with arthritis, gout, gallstones and kidney stones. The article describes this as a way the body spreads potential harm over time.

Is sea salt beneficial too?

The article notes that rock salts are essentially ancient sea salts formed in earlier geological periods. It therefore says unrefined sea salt may have characteristics similar to rock salt, but argues that much of the sea salt sold commercially is refined, may be exposed to environmental contaminants and can be more expensive than rock salt.

How can we tell whether a salt has been refined?

The source suggests a simple household test: if salt flows very freely, it may be refined. It recommends adding one teaspoon of salt to half a tea glass of grape vinegar, waiting five to ten minutes and observing whether the vinegar foams upward and becomes cloudy. The article claims that such a reaction indicates the salt is not natural.

Is Himalayan salt higher quality than our rock salt?

No, according to the article. It describes both as salts from ancient seas formed roughly 200–300 million years ago and says some Turkish deposits are even older. It jokes that those who want to spend more can, of course, use Himalayan salt.

Is Türkiye rich in natural salt resources?

Yes. Salt caves exist in several provinces, especially Çankırı, Iğdır and Kastamonu, and the crystal rock salt extracted from them is described in the article as a natural gift. The Çankırı Salt Cave is one of Türkiye's major rock-salt reserves and is believed to have been used for about 5,000 years, possibly since the Hittite period.

How much salt should we consume per day?

Up to this point, the article has argued that excess salt does not play as large a role in the development of high blood pressure as commonly claimed. It says public campaigns may overstate salt restriction and expresses concern that blindly following very restrictive advice may sometimes do more harm than good.

The author says that, provided attention is paid to quality and quantity, salt should not be regarded as an enemy but as an ancient companion. Salt is described as indispensable to life, and the article notes that about three quarters of the Earth's surface is covered by salty seas.

The article also states that much of the human body consists of water and salts. It describes salt as important for fluid balance, nerve signaling, muscle contraction and the movement of nutrients into cells.

It cites estimated daily salt consumption of about 18 grams per person in Türkiye and about 10 grams in the United States, calling both amounts high. The source then gives a claimed daily renal salt-filtering capacity of 5–7 grams, depending on sex, age and individual characteristics, and says this may be higher in people who drink more water and consume rock salt.

The article says that in a modern diet only about one quarter of salt intake comes from table salt, while three quarters comes from salt and sodium compounds added to processed foods.

It lists monosodium glutamate, sodium benzoate, sodium bicarbonate, sodium nitrate and sodium saccharin as examples of sodium compounds in shelf-stable foods. Because these do not all taste salty, the article argues that people may consume large amounts of sodium without realizing it and says many such additives may be undesirable.

It also claims that food manufacturers may exceed recommended sodium levels. As an example, it says authorities recommend no more than 500 mg of sodium per 100 g of food, while some processed meats such as salami and sausage may contain around 800 mg per 100 g.

Why is salt added to processed foods?

Before refrigeration, salting was one of the main ways to preserve food because salt inhibits many spoilage organisms. Although refrigeration and chemical preservatives have reduced this need, the article notes that packaged foods still often contain large amounts of salt.

Why?

Salt does more than extend shelf life. The article argues that highly processed foods would be bland without it and that salt is a cheap way to add flavor. It also acts as a stabilizer, helping ingredients in packaged foods remain together.

So we are consuming a lot of sodium without realizing it?

Exactly, according to the article.

After all this information, let me ask again: how many grams of salt should we consume each day?

The source states that the U.S. FDA recommendation at the time was not to exceed 2.4 grams per day and that the American Heart Association used an upper limit of 1.5 grams. It criticizes both organizations for not distinguishing between refined and unrefined salt.

The author then gives his own view: 5–7 grams of salt per day, based on the claimed daily filtering capacity of the kidneys. He adds that this capacity may be higher in people who drink more water and consume rock salt, even reaching 15 grams according to the article.

The article further suggests that people who use rock salt and avoid refined foods can season to taste, while also recommending at least two liters of water per day and increased water intake if more salt has been consumed.

Why, then, do authorities tell us to restrict salt?

The article says many physicians recommend a reduced-salt diet for the treatment and prevention of hypertension, regardless of whether a person is ill. It argues that they do this in good faith but may not realize, in the author's view, that the recommendation can be mistaken.

At first glance salt restriction in people with high blood pressure appears logical: more salt in the blood can draw water from cells into the circulation, increasing fluid volume and blood pressure. But, the article argues, the body is not a closed system; the kidneys can excrete excess salt when sufficient water is consumed.

When salt is low, the article explains, the renin–angiotensin–aldosterone system becomes activated. It says this hormonal system constricts blood vessels and reduces urinary sodium loss, retaining sodium. On this basis, the author argues that very low salt intake may itself promote vasoconstriction and increase blood pressure.

In the author's view, a patient's sodium requirement should be assessed by monitoring blood sodium, giving a reference range of 136–145 mEq/L and an ideal around 140. The article suggests reducing salt if values exceed 145 mEq/L and also discusses urinary sodium as a more sensitive indicator. It cautions that lowering sodium further in patients whose sodium is already low can be dangerous.

In salt-losing disorders such as adrenal insufficiency and cystic fibrosis, the article says higher salt intake may be required. It also argues that excessive restriction can adversely affect the kidneys and blood pressure and therefore requires caution.

In conditions such as congestive heart failure and kidney failure, where excretion of water and salt is impaired, the article says salt intake should be reduced. It states that treatment should be adjusted under medical supervision using blood and urinary sodium measurements.

Professor, there is a salty solution called “sole” that is said to be very beneficial. Is that true?

The article defines sole as a mixture of water and crystal salt. It says “sol” means sun in Latin and describes sole metaphorically as liquefied sunlight. It then gives an ion-based explanation in which positive and negative ions of water and salt surround one another and the geometric structures of salt and water change to form a new three-dimensional structure.

It further claims that this crystalline structure shares nature's resonance frequency and vibration pattern, that it can increase the body's conductivity, shift body pH toward the alkaline side and help eliminate heavy metals.

How can we prepare this sole?

The source gives the following method: place salt crystals in a glass container, fill it with water, and after 24 hours check whether the salt has dissolved. If all the salt dissolves, add more crystals; if crystals remain, the solution is described as saturated at about 25%. It recommends replenishing crystals and water as the solution is used. The article then instructs taking one teaspoon of this solution each morning on an empty stomach, diluting it in a glass of drinking water, and drinking 8–10 glasses of water through the day. It also claims the concentrated solution has a disinfecting effect and can be stored for a long time at room temperature.

I have also heard that sole is used for skin cleansing.

Yes, the article says. It suggests diluting 50 mL of concentrated sole in one liter of water, applying the solution with cotton, allowing it to dry and then rinsing with clean water. For the back and décolletage, it suggests soaking and wringing out a cotton shirt, wearing it while damp, allowing it to dry, and then showering with clean water. The source claims this may also help itching and insect bites.

Does salt have other uses related to human health?

Yes, the article says—for example, salt bath water.

For a salt bath, the source suggests dissolving 0.5–1 kg of crystal salt in a bathtub at approximately body temperature and remaining in the water for at least 20 minutes (11). It then suggests drying with a towel without rinsing and attributes detoxifying, moisturizing, anti-itch, relaxing and fatigue-reducing effects to the bath, comparing it with seawater.

For a 1% salt solution, the article suggests dissolving one level teaspoon (1 gram) of salt in a standard tea glass (100 mL) of water. It says this concentration is close to physiological saline and suggests using it to rinse the nose and sinuses, and even irritated eyes. It also says the same solution can be used as a gargle for sore throat.

What about Çankırı salt lamps—what do they do besides decoration? The article says crystal lamps are hand-carved to preserve the unique natural shape and crystal structure of rock salt and claims that crystal salt lamps improve air quality by producing negative ions (12).

The article claims that salt has a vibration frequency similar to the human body and says that brain electrical activity is around 8 Hertz, asserting that crystal salt lamps emit the same frequency.

It further claims that watching television exposes people to frequencies around 100–160 Hertz and that prolonged exposure can cause irritability. It suggests that salt lamps can reduce alleged harm from television and computers and says radioactive waste is stored in salt deposits as an example of salt's relationship with radiation.

The article describes rock salt as a natural ionizer and claims salt lamps improve air quality by producing negative ions. It also claims they reduce the harmful effects of positive ions associated with modern electrical devices. Although it notes that salt lamps are not medical devices, the source attributes benefits for fatigue, stress, asthma attacks, allergies, headaches, skin problems, humidity, odors, sleep, blood pressure and psychological problems.

It also claims that negative ions remove dust, pollen, animal dander, mold spores, odors and smoke from the air and links removal of positive ions with conditions such as hay fever, asthma, depression and chronic fatigue. The article says chloride ions in rock salt neutralize positively charged ions in the air and presents crystal salt lamps as a natural, low-maintenance alternative to manufactured ionizers.

REFERENCES

  1. Mark Kurlansky. Salt: A World History / Turkish edition: İnsanlığın Tuzlu Tarihi – Aykırı Yayıncılık, Istanbul, 2003
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  7. Alderman MH, Madhavan S, Cohen H, Sealey JE, Laragh JH. Low urinary sodium is associated with greater risk of myocardial infarction among treated hypertensive men. Hypertension. 1995;25(6):1144-52.
  8. Alderman MH, Cohen H, Madhavan S. Dietary sodium intake and mortality: the National Health and Nutrition Examination Survey (NHANES 1). Lancet1998; 351 : 781-785.
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  10. Cohen HW, Hailpern SM, Fang J, Alderman MH. Sodium intake and mortality in the NHANES II follow-upstudy. Am J Med. 2006;119(3):275.e7-14.
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  12. Stolarz-Skrzypek K, Kuznetsova T, Thijs L, Tikhonoff V, Seidlerová J, Richart T, Jin Y, Olszanecka A, Malyutina S, Casiglia E, Filipovský J, Kawecka-Jaszcz K, Nikitin Y, Staessen JA; European Project on Genes in Hypertension (EPOGH) Investigators. Fatal and nonfatal outcomes, incidence of hypertension and blood pressure changes in relation to urinary sodium excretion. JAMA. 201;305(17):1777-85.
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  20. http://www.iyibilgi.com/haber.php?haber_id=160003
  21. Schrauzer GN, Shrestha KP, Flores-Arce MP. Lithium in scalp hair of adults, students and violent criminals. Effects of supplementation and evidence for interactions of lithium with Vitamin B and other trace elements. Biological Trace Element Research, 1992(2): 161–76.
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Prof. Dr. Ahmet Aydın

Istanbul University Cerrahpaşa Faculty of Medicine

Department of Pediatrics

Head of the Division of Nutrition and Metabolism

Born in Istanbul in 1953. He graduated from Hobyarlı Ahmet Paşa Primary School in Istanbul, Samsun Anatolian High School and Ankara Science High School.

He graduated from Cerrahpaşa Faculty of Medicine in 1977 and completed his specialization in Pediatrics at the same faculty in 1982. Between 1982 and 1986 he completed military service in Çorlu and compulsory public service in Eskişehir. After returning to Cerrahpaşa Faculty of Medicine, he became an associate professor in 1988, head of the Division of Metabolism and Nutrition in 1993, and a professor in 1994.

Married with one child, Aydın authored six books on various subjects and more than 100 articles published in Türkiye and abroad.