I’m sure you’ve heard that diets high in sodium can increase your risk of high blood pressure, which in turn raises your risk of heart disease, stroke, and other cardiovascular problems. But, new research indicates that sodium overload can hurt way more than just your ticker. It can also weaken your immune system!

I’m sure you’ve heard that diets high in sodium can increase your risk of high blood pressure, which in turn raises your risk of heart disease, stroke, and other cardiovascular problems. But, new research indicates that sodium overload can hurt way more than just your ticker. It can also weaken your immune system!

Specifically, a study published in Science Translational Medicine, found that a diet high in salt (sodium chloride) can make it more difficult for the immune system to fight off certain bacteria.

Health Risks related to Salt

Interestingly, older research has shown that too much salt intake actually facilitates healing of skin that’s infected with parasites. But in this most recent study, researchers in Germany discovered that elevated sodium levels had the opposite effect, worsening E. coli infections in the kidneys of mice.

To see if other organ systems were similarly affected, the researchers infected the mice with another bacterium—Listeria. They discovered that the mice that were on a high-sodium diet had a much more significant body-wide infection than the mice that were on a regular diet. The researchers noted that the livers and spleens of the high-sodium mice had between 10 and 100 times more bacteria than the control mice.

A key reason for this impaired ability to fight infections has to do with immune cells called neutrophils. A type of white blood cell, neutrophils are responsible for attacking and killing harmful microbes (bacteria, viruses, fungi, etc.).

Back to the kidney connection…your kidneys are able to detect excess sodium in your bloodstream and help balance levels by excreting that extra sodium when you urinate. This entire process, though, raises levels of other compounds, such as hormones called glucocorticoids and the waste product urea.

Both glucocorticoids and urea inhibit the action of neutrophils. This means harmful bacteria aren’t neutralized and are able to continue to infect and make you sick.

Limit Your Salt, Protect Your Heart Health & Immune Function

It would stand to reason that reducing salt intake would be a simple thing to do. But in reality, the Centers for Disease Control and Prevention says that 9 out of 10 Americans consume far more salt than the recommended amount every day. The general recommendation is 2.3 grams of sodium per day, which is the equivalent of about one level teaspoon of salt.

Sadly, the typical American diet, rich in processed/fast food, is very heavy in salt. This latest study emphasizes yet again why a healthy diet is one of the most important things you can do to get and stay healthy.

How To Reduce Your Salt Intake?

While a strong immune system is on everyone’s mind right now, if there’s one goal you should make for yourself, starting right now, it’s to try and lower your sodium intake.

Here are some simple ways you can do just that:

• Limit your consumption of processed food. Anything in a box or a can is likely to have a lot of salt, unless it’s labeled as “low sodium,” “reduced sodium” or “no added salt.” If you need to buy something in a box, can, or jar, check the label to see how much sodium it has, and plan your meals appropriately so that you stay in the 2.3- grams-of-sodium-per-day guideline.

• Prepare the majority of meals you eat with fresh, whole foods and natural ingredients. Fresh fruits and veggies are naturally very low in sodium. The Mediterranean and Nordic diets tend to be great options if you want to keep salt intake low without sacrificing flavor and fun/interesting options.

• Buy fresh meat and poultry instead of cured, salted, smoked, or processed varieties, which have a lot of added salt—a known factor in higher risk of developing cardiovascular disease.

• Cook most of your meals at home instead of eating out or ordering takeout from your preferred app-based delivery service. I know this is hard, especially with some restaurants opening back up and many of us are weary of cooking yet another meal at home. However, most restaurant meals (and especially fast food) are notoriously high in salt.

• If you do eat out, split your meal in half—eat one half there and take the rest home to enjoy for lunch the next day. And make eating out an occasional treat, rather than a frequent occurrence.

• When cooking, use spices to add flavor instead of salt.

Considering we’re still in the middle of a pandemic, protecting your body’s immune function is of the utmost importance. And keeping your sodium levels and other risk factors in check may prove to be an essential way to do that.

Last Updated: May 21, 2021