MS and Dietary Sodium: What You Should Know

Research is finally beginning to look at the role of diet in multiple sclerosis, which is a very good thing! Several studies are looking at various aspects of diet. One area being studied is dietary sodium and it’s impact on the immune system — and what that means for folks with MS.

You may be familiar with the fact that a high sodium diet increases the risk of having high blood pressure. Salt plays a role in balancing the sodium and water in the body; too much sodium can cause your body to retain water, which places extra burden on your blood vessels, and heart and can lead to high blood pressure.

So, the only reason to limit sodium intake is to protect against high blood pressure and the strain it puts on the heart, right?  Not really.  A high sodium diet has been linked to a number of other health concerns including osteoporosis and stomach cancer.  And, remember that high blood pressure is one of the common comorbidities (the presence of more than one disease or condition in the same person at the same time) associated with multiple sclerosis. Evidence shows that individuals with MS that have comorbidities experience decreased quality of life and and an increase in disability. If you have MS, you have a number of motivations to reduce your dietary sodium intake!

But there is more…

Recent research suggests that diets high in sodium may increase relapse rate and MRI disease activity in individuals with Multiple Sclerosis. In mice, a high salt diet has been shown to lead to a more severe form of experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. The results of a human observational study in Argentina suggest that a higher sodium intake is associated with increased clinical and radiological disease activity in patients with MS. Something I found interesting about this study is that the average daily sodium intake for the study population was 4120±1600 mg/day.  That’s a lot of salt! The RDA for sodium is 2300 mg/day and the American Heart Association encourages a goal of 1500 mg/day.

Researchers at Brigham and Women’s Hospital in Boston is currently conducting research to evaluate the association between sodium and TH17 cells in human subjects and determine if salt intake has the same adverse impact in humans that it does in mice.. TH17 cells are immune system cells that help to protect the body against pathogens. They do not attack pathogens directly but rather they secrete inflammatory cytokines such as interleukins.  Study  subjects will have levels of TH-17 and various hormones measured on low salt diet, low salt diet with intravenous normal saline, and high salt diet. You can read more about this research here.

Do you know how much sodium you are eating?

Probably not. Many people think that if they just eliminate the salt shaker from the kitchen they will be sufficiently reducing their salt intake but… 77% of sodium intake comes from processed, packaged and restaurant foods.  Some salt occurs naturally in foods but foods that are highly processed or are otherwise packaged for your convenience contain significantly higher amounts of sodium.

The American Heart Association released an infographic titled “75% of Americans Want Less Sodium in Processed and Restaurant Food,” which you can view in full in this PDF.

Reducing sodium intake is a good idea for everyone including people with MS — perhaps even especially people with MS. Cutting way back on heavily processed and convenience food products is a good place to start but salt is everywhere and it can add up quickly. Download and print out this handy sodium tracker (PDF) from the American Heart Association to help you get a better understanding of where your sodium intake comes from each day as well as to see how your current diet compares to the RDA.

What is the DASH Diet?

The DASH Diet is an eating pattern intended to prevent and lower high blood pressure but is appropriate for everyone to follow — including folks with MS. It was actually named the best overall diet of 2015 by U.S. News and World Report. “DASH” stands for “Dietary Approaches to Stop Hypertension”, and is a flexible, balanced and sustainable eating plan that is based on research  by the National Heart, Lung, and Blood Institute (NHLBI). These studies showed that DASH lowers high blood pressure and improves levels of blood lipids (fats in the bloodstream), which reduces the risk of developing cardiovascular disease. It is a healthy approach to eating that can help to maintain optimal health. If you are looking for a dietary guideline that will help you be healthier and focus on reducing your dietary sodium intake consider the DASH eating pattern.

The DASH Diet:

• Emphasizes vegetables, fruits, and fat-free or low-fat dairy products
• Includes whole grains, fish, poultry, beans, seeds, nuts, and vegetable oils
• Limits sodium, sweets, sugary beverages, and red meats

In terms of nutrition content, the DASH Diet is:

• Low in saturated and trans fats
• Rich in potassium, calcium, magnesium, fiber, and protein
• Lower in sodium than the typical American diet

Daily Nutrient Goals Used in the DASH Studies (for a 2,000-Calorie Eating Plan)

* 1,500 mg of sodium was a lower goal tested and found to be even better for lowering blood pressure. It worked very well for people who already had high blood pressure, African Americans, and middle-aged and older adults.*

Tips for reducing dietary sodium intake

• Read the nutrition label to help you choose lower sodium options. A good rule of thumb: If salt is listed in the first five ingredients, the item is too high in sodium.

• Sometimes it can be confusing to know what all of the claims on the label mean. Whats the difference between low sodium and no added salt? What is the difference between low sodium and reduced sodium? It can be tricky.  You will need to compare products and use the information on this chart to better understand the various health claims:

• A product that provides 5%DV (120 mg) or less of sodium per serving is low.
• A product that provides 20%DV (480 mg) or more of sodium per serving is high.
• Cook more meals at home. That way you are in control of what is in your food and how it is seasoned. 
• If you are purchasing a convenience product opt for the lowest sodium option available. Frozen dinners, pizza, packaged baking mixes, canned soups and broths and salad dressings can be high in sodium.
• Eat lots of vegetables and fruits which are naturally low in sodium. Fresh or frozen are best; canned veggies should be rinsed well to remove a lot of the salt.
• If you are a meat eater, opt for fresh poultry, fish or lean meats rather than canned, smoked or other highly processed varieties which can be high in sodium.
• Limit cured foods such as bacon and ham
• Limit foods packed in brine such as pickles, olives and sauerkraut
• Eat less cheese which can be high in sodium.
• Nuts are a great snack but opt for unsalted varieties.
• When dining out, ask for your meal to be cooked without added salt (when possible) and ask for gravy, sauces, and dressings served on the side. This request should be made realistically. For example, it is unlikely that a restaurant specializing in BBQ Ribs & fries or has a drive thru attached to the building will be able to alter the sodium in your food very drastically.
• Limit or avoid drive thru restaurants.
• Skip the salt when cooking. Keep it off the counter and the dining table. Use spices, herbs, garlic, vinegar, lemon juice, pepper etc to season your foods.

FYI: The Recommended Daily Allowance (RDA) for sodium is 2300 mg. 1 teaspoon of table salt contains 2300 mg of sodium.

• Cook rice, pasta and hot cereals without salt. Cut back or avoid “instant” or “flavored” rice, cereal or pasta products.
• Avoid seasonings with salt in it (example “garlic salt” vs “garlic powder”). Chili powder is another seasoning that often contains salt but doesn’t need to.
• Mrs Dash is an easy to find product available in several flavor combinations that will help you to learn to love the “taste of taste” again.

The American Heart Association has a lot of great nutrition information on their website, and here is one last resource from them, The Salty 6 (PDF).

Lastly, it is important that you know that ANY BIG CHANGE takes time.

Be kind to yourself. Cut back a little at a time to allow your taste buds an opportunity to make the change. Your taste for salt will lessen over time, really.

• Farez M., Fiol M., Gaitán M., Quintana F., Correale J. Sodium intake is associated with increased disease activity in multiple sclerosis. J Neurol Neurosurg Psychiatry. 2015 Jan;86(1):26-31. doi: 10.1136/jnnp-2014-307928. Epub 2014 Aug 28.
• Kleinewietfeld M., Manzel A., Titze J., Kvakan H., Yosef N., Linker R. A., Hafler D. A. Sodium chloride drives autoimmune disease by the induction of pathogenic TH17 cells. Nature (2013) 496: 518–522.
• National Heart, Lung and Blood Institute. What is the DASH eating Plan? https://www.nhlbi.nih.gov/health/health-topics/topics/dash
• Wu C., Yosef N., Thalhamer T., Zhu C., Xiao S., Kishi Y., Kuchroo V. K. Induction of pathogenic TH17 cells by inducible salt-sensing kinase SGK1. Nature (2013) 496: 513–517.