The Salt Myth – How Much Sodium Should You Eat Per Day?
“Salt is what makes things taste bad when it isn’t in them.” – Unknown
Sodium is one of those things that everyone “knows” is unhealthy… kind of like saturated fat.
The government has been warning us about it for decades and has spent a massive amount of resources warning us about the “dangers” of it. The reason they do so, is that sodium is believed to increase blood pressure, a common risk factor for heart disease and stroke. These are the two most common sources of death in middle- and high income countries.
The major health organizations recommend that we cut back on sodium:
- United States Department of Agriculture (USDA): 2300 mg.
- American Heart Association (AHA): 1500 mg.
- Academy of Nutrition and Dietetics (AND): 1500 to 2300 mg.
- American Diabetes Association (ADA): 1500 to 2300 mg.
So… there is definitely a consensus among these organizations that we should aim for less than 1500 mg of sodium per day, and definitely not more than 2300 mg. Keep in mind that salt contains both sodium and chloride. Only 40% of the weight of salt consists of sodium, so you can actually eat 2.5 times more salt than sodium. 1500 mg of sodium amounts to 0.75 teaspoons or 3.75 grams of salt per day, while 2300 mg amounts to one teaspoon or 6 grams of salt per day.
Most people today are eating much more than that. The average intake of sodium is about 3400 mg, most of it coming from processed foods. If these health organizations have their way, all of us need to make drastic changes in our food choices, start reading labels and start to actively restrict the amount of sodium in our diets. I have to say, I’m skeptical… these health organizations do have a track record of getting things wrong in the past, such as the misguided low-fat dietary guidelines.
So is sodium really that bad? Do the studies show that reducing sodium intake actually leads to improved health? And more importantly… if there are benefits to sodium restriction, are they important enough to be worth the obvious reduction in pleasure we will derive from our (now tasteless, salt-free) foods?
Let’s find out…
Sodium – What is it and Why do we Care?
Sodium is a crucial electrolyte in the body. Many foods contain small amounts of sodium naturally, but most of the sodium in the diet comes from salt. Salt is made of sodium (40% by weight) and chloride (60% by weight).
What sodium does in the body is to bind water and maintain intracellular and extracellular fluids in the right balance. It is also an electrically charged molecule, and along with potassium helps maintain electrical gradients across cell membranes, which is critical for nerve transmission, muscular contraction, and various other functions.
The body can NOT function without sodium. Period. The more sodium we have in our bloodstream, the more water it binds. For this reason, sodium is thought to increase blood pressure (which it does, but only mildly).
If blood pressure is elevated, the heart has to work harder to push the blood throughout the body and there is increased strain on the arteries and various organs.
High blood pressure (hypertension) is a major risk factor for many serious diseases, like heart disease, stroke and kidney failure.
Reducing Sodium Can Mildly Lower Blood Pressure
It is definitely true that reducing sodium can lower blood pressure, but the effect isn’t as strong as you may think. In a massive Cochrane review of 34 randomized controlled trials, salt restriction was shown to reduce blood pressure:
- Individuals with elevated blood pressure: A reduction of 5.39 mm Hg systolic and 2.82 mm Hg for diastolic.
- Individuals with normal blood pressure: A reduction of 2.42 mm Hg systolic and 1.00 mm Hg for diastolic.
Be aware that these numbers are only averages. Some people may have seen impressive reductions, while others little to no effects. As with most things in nutrition, the results depend on the individual.
Sodium Restriction… Does it Even Work?
Doctors and nutritionists tell us to cut back on sodium because they believe that it will reduce our risk of serious diseases. However, it’s important to keep in mind that blood pressure itself doesn’t kill anyone directly. It’s a risk factor, not necessarily a cause of disease. Even though some intervention successfully lowers a risk factor, it doesn’t mean that this automatically reduces the risk of disease, especially if the intervention causes other adverse effects that outweigh the benefit. When studies examine the effects of sodium restriction on actual disease, instead of just some marker, no statistically significant effects are found.
Another Cochrane review of 7 randomized controlled trials (the gold standard of research) noted that there is no effect on mortality or cardiovascular disease, even in individuals diagnosed with high blood pressure!
Other studies confirm these findings. There is no benefit to sodium restriction when it comes to preventing heart disease or death.
Too Little Sodium Can Cause Downright Harm
The health authorities do have an excellent track record of getting things wrong. They’ve given us a lot of bad advice in the past, such as telling us to cut back on saturated fat and eat 50-60% of calories as carbohydrates.
It looks like the advice on sodium is bad advice too. Not only is it probably useless for the majority of people, these guidelines may even cause downright harm.
Multiple studies show that salt restriction causes adverse effects on health:
- Increased LDL and Triglycerides: In a massive review, low sodium diets were found to cause an increase in LDL (the “bad” cholesterol) by 4.6% and an increase in triglycerides by 5.9%.
- Insulin resistance: In one study, just 7 days on a low sodium diet increased insulin resistance, a leading cause of obesity, diabetes and metabolic syndrome.
- Type II Diabetes: A study found that in patients with type II diabetes, less sodium was associated with an increased risk of death.
- Hyponatremia: In athletes, a low sodium intake can cause hyponatremia, a sodium deficiency which can be very dangerous.
The Importance of Other Dietary Factors
There are many lifestyle factors that can influence blood pressure to an even greater degree than sodium restriction. Some of them include the minerals magnesium and potassium, which you should be getting if you eat plenty of animals and plants.
Another way is to indulge in a bit of dark chocolate every now and then. A low-carb diet lowers insulin levels, which causes the kidneys to excrete excess sodium from the body. Low-carb diets are an excellent way to reduce blood pressure and improve health. And last but not least, exercise is a very powerful way to reduce blood pressure and will improve your health in more ways than you can imagine. It seems fairly ridiculous to me to blindly focus on sodium, when there are so many other lifestyle factors that can have a much stronger effect.
How Much Sodium is Optimal?
If your doctor has recommended that you limit sodium for whatever reason, then by all means continue to do so. However, for people who are generally healthy and want to stay healthy, there doesn’t seem to be any reason to be even remotely concerned about moderate intakes of sodium.
Studies actually show that the effects of sodium may follow a J-shaped curve. Too little and too much are both harmful, the sweet spot is somewhere in between. Also be aware that if you’re on a low-carb diet, your sodium requirement may go up. It is probably best to consume unrefined varieties of salt, such as sea salt and Himalayan pink salt. They also contain various trace nutrients that may be important.
Given that most people get most of their sodium from processed foods and that studies on sodium restriction don’t show any benefit, then I’d like to propose this radical approach to optimizing your sodium intake.
No obsessive counting of milligrams required:
- Eat real food.
- Add salt whenever appropriate to make your food taste good.
- That’s it.
Types of Salt: Himalayan vs Kosher vs Regular vs Sea Salt
“Salt is what makes things taste bad when it isn’t in them.” – Unknown
Salt is arguably the most important ingredient in cooking. Without it, most meals would taste bland and unexciting. However… not all salt is created equal and there are many “types” to choose from.
We have Himalayan Pink Salt, Kosher Salt, Sea Salt, Celtic Salt (to name a few)… and then we have plain old refined table salt. Not only do they differ in taste and texture, but there are also some differences in mineral and sodium content.
This article explores the most popular salt types… then at the end, gives you a direct comparison of their nutritional properties to help you make the right choices. But first, let’s take a look at what salt is and why it’s such a controversial ingredient among health experts.
What is Salt and How Does it Affect Health?
Salt is a crystalline mineral made of two elements, sodium (Na) and chlorine (Cl). Sodium and chlorine are absolutely essential for life in animals, including humans. They serve important functions like helping the brain and nerves send electrical impulses. Most of the world’s salt is harvested from salt mines, or by evaporating sea water or other mineral-rich waters.
Salt is used for various purposes, the most common of which is adding flavor to foods. Salt is also used as a food preservative, because bacteria have trouble growing in a salt-rich environment. The reason salt is often perceived as unhealthy (in large amounts), is that it can bind water in the bloodstream and raise blood pressure. But even though studies have suggested that lowering salt intake can reduce blood pressure by 1-5.4 mm/Hg, there is no evidence that lowering salt prevents heart attacks, stroke or death.
The great majority of sodium in the Western diet comes from processed foods. If you eat mostly whole, unprocessed foods then you don’t need to worry about adding some salt to your meals.
Bottom Line: Salt is made of two minerals, sodium and chloride, which are essential for human life. Too much salt can raise blood pressure, but there is very little evidence that eating less salt can improve health.
Refined Salt (Regular Table Salt)
The most commonly used salt is plain old table salt. This salt is usually highly refined. It is heavily ground and most of the impurities and trace minerals are removed. The problem with heavily ground salt is that it can clump together. For this reason, various substances called anti-caking agents are added so that it flows freely.
Food-grade table salt is almost pure sodium chloride, or 97% or higher.
Here’s an important point… iodine is often added to table salt. This was a successful public health preventative measure against iodine deficiency, which was (and still is) common in many parts of the world and a leading cause of hypothyroidism, mental retardation and various health problems. Therefore, if you choose not to eat regular iodine-enriched table salt, then make sure you’re eating some other foods that are high in iodine, like fish, dairy, eggs and seaweed.
I personally take kelp tablets (seaweed) a few times per week because I rarely eat iodized salt. They are very high in iodine.
Bottom Line: Refined table salt is mostly just sodium chloride, with substances called anti-caking agents added in order to prevent clumping. Iodine is often added to table salt.
Sea salt is made by evaporating seawater. Like table salt, it is mostly just sodium chloride. However, depending on where it is harvested and how it was processed, it usually does contain some amount of trace minerals like potassium, iron and zinc. The darker the sea salt, the higher its concentration of “impurities” and trace nutrients will be. However, keep in mind that due to the pollution of oceans, sea salt can also contain trace amounts of heavy metals like lead.
Sea salt is often less ground than regular refined salt, so if you sprinkle it on top of your food after it has been cooked, it may have a different mouthfeel and cause a more potent “flavor burst” than refined salt.
The trace minerals and impurities found in sea salt can also affect the taste, but this varies greatly between different brands.
Bottom Line: Sea salt is made by evaporating seawater. It is very similar to regular salt, but can contain small amounts of minerals. It can also contain trace amounts of heavy metals if it is harvested from a polluted sea.
Himalayan Pink Salt
Himalayan salt is harvested in Pakistan. It is mined from the Khewra Salt Mine, the second largest salt mine in the world. Himalayan salt often contains trace amounts of iron oxide (rust), which gives it a pink color.
It does contain small amounts of calcium, iron, potassium and magnesium. It also contains slightly lower amounts of sodium than regular salt.
A lot of people prefer the flavor of himalayan salt compared to other types of salts, but personally I haven’t been able to notice a difference. The main difference seems to be the color, which can give a meal a nice look if you sprinkle it on top after it has been cooked.
Bottom Line: Himalayan salt is harvested from a large salt mine in Pakistan. It has a pink color due to the presence of iron oxide. It also contains trace amounts of calcium, potassium and magnesium.
Kosher salt is called “kosher” because it is useful for the Jewish religion. Jewish law requires blood to be extracted from meat before it is eaten. Kosher salt has a flaky, coarse structure that is particularly efficient at extracting the blood.
The main difference between regular salt and kosher salt is the structure of the flakes. Chefs find that kosher salt, due to its large flake size, is easier to pick up with your fingers and spread over food.
Kosher salt will have a different texture and flavor burst, but if you allow the salt to dissolve in the food, then there really isn’t any difference compared to regular table salt. However, kosher salt is less likely to contain additives like anti-caking agents and iodine.
Bottom Line: Kosher salt has a flaky structure that makes it easy to spread on top of your food. There is very little difference compared to regular salt, although it is less likely to contain anti-caking agents and added iodine.
Celtic salt is a type of salt that originally became popular in France. It has a greyish color and also contains a bit of water, which makes it quite moist. Celtic salt contains trace amounts of minerals and is a bit lower in sodium than plain table salt.
Bottom Line: Celtic salt has a light greyish color and is quite moist. It is made from seawater and contains trace amounts of minerals.
Differences In Taste
Foodies and chefs primarily choose their salt based on taste, texture, color and convenience. The impurities, including the trace minerals, can affect both the color and taste of the salt. The size of the salt can also affect how the salty flavor hits the tongue. Salt with a larger grain size can have a stronger flavor and last longer on your tongue.
However, if you allow the salt to dissolve in the food, then there shouldn’t be any major taste difference between plain refined salt and the other “gourmet” types of salt. If you like to use your fingers to sprinkle salt on food, then dry salts with a larger grain size are much easier to handle.
Bottom Line: The main difference between the salts is the taste, flavour, color, texture and convenience.
Minerals in Different Types of Salt
There is one study that compared the mineral content of different types of salt. The table below shows the comparison between Table Salt, Maldon Salt (a typical sea salt), Himalayan Salt and Celtic Salt:
As you can see, celtic salt has the least amount of sodium and the highest amount of calcium and magnesium. Himalayan salt contains a bit of potassium. However… keep in mind that these really are tiny amounts. For example, the 0.3% content of Magnesium for celtic salt implies that you would need to eat 100 grams of salt to reach the recommended daily amount. For this reason, the mineral content of the various salts is actually not a compelling reason to choose one salt over the other. These amounts really are negligible compared to what you get from food.
Which Salt is The Healthiest?
I looked long and hard and couldn’t find a single study actually comparing the health effects of different types of salt. However… if such a study were done, I highly doubt they would find a major difference. Most of the salts are similar, consisting of sodium chloride and tiny amounts of minerals. The main benefit of choosing more “natural” types of salt is that you avoid additives and anti-caking agents that are often added to regular table salt.
At the end of the day, salt is salt… its main purpose is to add flavor, not nutrition.