What is salt?
“Salt” is a mineral known as sodium chloride, which is 40% sodium and 60% chloride. It is by far the biggest dietary source of sodium, and the words “salt” and “sodium” are often used interchangeably.
Some varieties of salt contain trace amounts of other essential minerals like calcium, potassium, iron, and zinc. All of these minerals act as important electrolytes in the body, helping with fluid balance, nerve transmission, and muscle function.
The less refined a particular type of salt is, the higher the mineral content. What we know as “table salt” is highly refined to remove all other minerals, and usually has added iodine for thyroid support, plus an anti-caking agent.
Most foods naturally contain some salt, but salt is also frequently added to foods to improve their flavor. In fact, 75% of our salt intake comes from processed foods.
Historically, salt was used to preserve foods, as high amounts of salt can prevent the growth of bacteria that cause food to go bad.
Types of salt
Salt is harvested in two ways:
- from salt mines
- by evaporating sea water or other mineral-rich water
There are many different types of salt available, including pink Himalayan salt (its particular mineral content contributes to its color, and includes calcium, magnesium, potassium, copper, and iron), Celtic grey salt, fleur de sel from France, Hawaiian black salt (which gets its notable color from volcanic lava), and sea salt.
How much salt do we need?
Clearly, minerals and electrolytes are important, so we know we need some sodium, but how much? Health authorities recommend one teaspoon of added salt (2300 mg sodium) or less per day. Right now, 90% of US adults consume a lot more than that.
Make sure to read food labels to see how much salt is added to various foods. Some examples of foods that contain a lot of added salt:
- salted snack foods
- instant and canned soups
- processed meats
- pickled foods
- soy sauce
If you are prone to kidney stones, it’s recommended that your daily added sodium intake not exceed 1500 mg (read on to learn more about how salt affects the kidneys).
Benefits of sodium in your diet
Sodium is an essential mineral, and when eaten in moderation, it has many benefits in the body:
- regulates fluid levels
- prevents sunstroke
- relieves muscle cramps
- promotes oral health; using the old remedy of a saltwater gargle allows salt’s anesthetic properties to reduce tooth pain, strengthen gums, and reduce inflammation due to infection.
- supports healthy brain function
It’s important to maintain the right balance of salt to water ratio in the body. If your body loses too much salt compared to the ratio of water, a condition called hyponatremia can result. Think back to the Boston Marathon of 2002 when a runner died because she drank too much water without replacing the salt she lost through perspiration.
If you are highly active or sweat a lot, drink a lot of water and make sure you replace some of the salt you lose through sweating.
What can happen when we eat too much salt?
A high salt diet has been linked to stomach cancer, one of the leading causes of cancer worldwide. High amounts of salt can damage and inflame the stomach lining, exposing it to carcinogens. Too much salt can also increase the growth of H. pylori bacteria, which can lead to inflammation and gastric ulcers, thereby increasing the risk of stomach cancer.
Elevated sodium (which you’d find in a typical US meal, especially at a restaurant) suppresses arterial function. High amounts of sodium affect the function of the inner lining of your blood vessels, reducing their elasticity so they can’t stretch well with every pulse. They stiffen, and make it harder for the heart to pump blood. Eventually, the heart wears out, resulting in heart failure.
Salt also gets a bad rap when it comes to high blood pressure, with older studies showing that an increase in salt increases blood pressure across the board. But recent studies show that about a third of people who eat a higher salt diet do not experience high blood pressure. It appears to be the interaction between sugars/carbs and salt that really make the difference.
High insulin from high blood sugar and excess carbs makes you hold onto sodium. Excessive carb intake makes salt become more damaging. When carb intake is restricted, salt becomes more important.
Excess salt causes problems with the brain. Too much salt causes the sympathetic nervous system to overreact to stressful situations, pumping out chronically high levels of the stress hormone cortisol.
High salt intake can lead to a decrease in the filtration ability of the kidneys. This can lead to kidney disease, and if unchecked, ultimately to kidney failure. High sodium intake also means increased protein excretion by the kidneys, which can lead to both heart and kidney disease.
Kidney stones form when certain chemicals become concentrated enough in the urine to form crystals, which then grow into larger masses we call stones. Most stones occur when calcium combines with oxalate or phosphorus, but they can also form from uric acid which forms as the body metabolizes protein. Half of the people with a kidney stone who do not take preventive measures will get another one within seven years.
To avoid kidney stones:
- Drink plenty of water. Citrus helps too (lemon in your water, or fresh squeezed orange juice) because the citrate helps block stone formation.
- Get the calcium you need from foods. Too little calcium causes oxalate levels to rise, contributing to stone formation. Unfortunately, calcium supplements have also been linked to stones, so make sure your calcium comes from food. Contrary to popular belief, dairy is not the most bioavailable form of calcium (plus, it causes mucous production and inflammation in the body). To get more plant-based calcium, try eating a variety of seeds (pumpkin, sesame, sunflower, chia, etc.), sardines (which contain edible bones), beans and lentils, almonds, dark leafy greens, and dried figs.
- Reduce sodium intake. As we’ve already learned, sodium triggers stones because it increases calcium in the urine. Reduce your added sodium intake to 1500mg or less per day if you are prone to stones.
- Limit animal protein. Animal protein (including meat, eggs, and dairy) boost uric acid which contributes to stones. Consuming animal protein also causes a decrease in citrate, which prevents stones from forming.
How can we make sure we’re eating the right amount of salt?
Reduce processed foods. Remember: most processed foods contain a lot of added salt, and we get 75% of our excess salt from these foods. This goes for restaurant food as well. Minimize eating out, eat more whole foods, and cook from scratch.
If you are going to add some salt to your food, choose a more mineral-rich salt that has a broader mineral content than traditional table salt, which has been stripped of other minerals and only contains sodium chloride. See the list above for various types of salts, and remember that the color of the salt indicates that there are more minerals present.
You can also use trace mineral drops and add them to your drinking water to make sure you are replenishing essential minerals and micronutrients in addition to sodium.
Our taste buds are conditioned to want the flavor of salt because we are so overexposed to it, so when we eat natural foods, they may taste bland to us. Try doing a salt detox for a week to reset your taste buds to appreciate the subtle nuances and flavors in natural foods.
As with most aspects of health and nutrition, moderation is best: not too little, and not too much. Aim to stay under 2300 grams of sodium a day (under 1500 if stone-prone), and maybe just a pinch more if you are highly active and perspire a lot.