Salt intake is affecting your immunity
Table salt consists of sodium chloride. It supplies us with sodium, an important mineral that is essential for proper functioning of the human body. However, the American diet contains dangerously high amounts of sodium, almost 80 percent of which comes from processed and restaurant foods. The human diet, for millions of years, did not contain any added salt—only the sodium present in natural foods, which adds up to about 600–800 milligrams per day. The dietary intake of sodium in the United States today is about 3,500 milligrams per day.
Excess dietary salt is most notorious for increasing blood pressure.
Populations in pockets of the world that do not salt their food do not have elderly citizens with high blood pressure (also known as hypertension). Americans have a 90 percent lifetime probability of developing high blood pressure. So even if your blood pressure is normal now, if you continue to eat the typical American diet, you will be at risk.
Elevated blood pressure accounts for 62 percent of strokes and 49 percent of coronary heart disease. Notably, the risk for heart attack and stroke begins climbing with systolic pressures (the first number in the blood pressure reading) above 115—considered “normal” by most standards. Even if you eat an otherwise healthy diet, and your arteries are free of plaque, hypertension late in life damages the delicate blood vessels of the brain, increasing the risk of hemorrhagic stroke.
The American Heart Association, recognizing the significant risks of high blood pressure, has recently dropped their recommended maximum daily sodium intake from 2,300 milligrams to 1,500 milligrams.
Salt has additional dangerous effects that are not related to blood pressure. In the 1990s, it was found that the relationship between salt intake and stroke mortality was stronger than the relationship between blood pressure and stroke mortality; this result suggests that salt may have deleterious effects on the cardiovascular system that are not related to blood pressure. Likewise, high blood pressure causes kidney disease, but dietary sodium has damaging effects on the kidneys beyond the indirect effects of high blood pressure.
Further research has determined that long-term excess dietary sodium promotes excessive cell growth, leading to thickening of the vessel walls and altered production of structural proteins, leading to stiff blood vessels. In another study, higher sodium intake was associated with greater carotid artery wall thickness, an accurate predictor of future heart attacks and strokes—even in people without high blood pressure.
High salt intake is also a risk factor for osteoporosis, because excess dietary sodium promotes urinary calcium loss, leading to calcium loss from bones (and therefore decreased bone density). Daily sodium intakes characteristic of Americans have been associated with increased bone loss at the hip, and sodium restriction reduces markers of bone breakdown. Even in the presence of a high-calcium diet, high salt intake results in net calcium loss from bone.
Although postmenopausal women are most vulnerable to these calcium losses, high salt intake in young girls may prevent the attainment of peak bone mass during puberty, putting these girls at risk for osteoporosis later in life.
Salt is also the strongest factor relating to stomach cancer. Sodium intake statistics from twenty-four countries have been significantly correlated to stomach cancer mortality rates. Additional studies have found positive correlations between salt consumption and gastric cancer incidence. A high-salt diet also increases growth of the ulcer-promoting bacteria (H. pylori) in the stomach, which is a risk factor for gastric cancer.
Alarmingly, high sodium intake also correlates with death from all causes.
Reducing dietary salt is not only important for those who already have elevated blood pressure; limiting added salt is essential for all of us to remain in good health. Since natural foods supply us with 600–800 milligrams of sodium a day, it is wise to limit any additional sodium, over and above what is in natural food, to just a few hundred milligrams. I recommend no more than 1,000 milligrams total of sodium per day. That means not more than 200–400 milligrams over and above what is found in your natural foods.
It is also important to note that expensive and exotic sea salts are still salt. All salt originates from the sea—and so-called sea salts are still over 98 percent sodium chloride, contributing the same amount of sodium per teaspoon as regular salt. Sea salts may contain small amounts of trace minerals, but the amounts are insignificant compared to those in natural plant foods, and the excess sodium doesn’t magically become less harmful due to those minerals. A high-nutrient, vegetable-based diet with little or no added salt is ideal.
Salt also deadens the taste buds. This means that if you avoid highly salted and processed foods, you will regain your ability to detect and enjoy the subtle flavors in natural foods and actually experience heightened pleasure from natural, unsalted foods.
Since most salt comes from processed foods, avoiding added sodium isn’t difficult. Resist adding salt to foods, and purchase salt-free canned goods and soups. If you must salt your food, do so only after it is on the table and you are ready to eat it—it will taste saltier if the salt is right on the surface. Condiments such as ketchup, mustard, soy sauce, teriyaki sauce, and relish are all high in sodium. Use garlic, onion, fresh or dried herbs, spices, lemon or lime juice, or vinegar to flavor food. Experiment to find salt-free seasonings that you enjoy.