I used to think nothing of going to the health-food store a couple of times a year and grabbing one of the bottles of “high potency” multivitamin and mineral supplements. I would take these religiously for about four days, occasionally for the next week, then forget about them completely. I was partially drawn in by the advertisements claiming that the product was “loaded with antioxidants to stimulate the immune system.” Yikes.
I am a fan of antioxidants, especially those that we get through food. For those of us who might eat things that don’t so closely resemble food as they do a bunch of chemicals or laboratory formulations to taste good, it might be a good idea to consider an antioxidant supplement, as they really help us in so many ways. However, it is very important that this supplement not contain huge amounts of any of the antioxidants, including selenium, as this theoretically could stimulate the already overactive immune systems of those of us with multiple sclerosis (MS). Again, this is theoretical…
Why Should We Care About Selenium?
The results are mixed. In one Finnish study, the selenium levels in the blood of people with MS was lower than in that of people without MS, and in another study low selenium levels were found in the erythrocytes (red blood cells) of people with MS. However, other studies have found normal, or even higher, levels of selenium in the blood of people with MS.What Is It For?
Selenium is an essential mineral that is found in trace amounts in the body. It is an antioxidant. Some experts think that “oxidative stress” caused by free radicals plays a role in MS.How Does It Work?
Here’s a quick explanation: When the cells in our bodies use oxygen, they naturally produce free radicals. Free radicals are unstable molecules that are missing an electron. They can cause damage to cells in our bodies as they seek to “steal” electrons from other molecules. Antioxidants are substances that can prevent or slow the oxidative damage to our body, by “donating” one of their molecules to make the free radical stable.How Effective Is It?
In one study of animals with EAE, the animal model of MS, selenium supplementation worsened their disease and increased mortality. A small (18 people), short (5 weeks) study examined the effects of selenium supplementation on people with MS. It improved the levels of selenium in the erythrocytes, but failed to show any clinical benefit. Again, the study was too small and too short to yield any definitive conclusions.Usual Dosage/How Taken
Selenium can be taken in pill or capsule form (either alone or in combination with other antioxidants) in dosages up to 200 micrograms daily. The Recommended Dietary Allowance is 55 mcg for adult women and 75 mcg for men.Dietary sources of selenium include:
- Brewer’s yeast
- Wheat germ
- Shellfish (lobster, shrimp, scallops, oysters)
- Fish (salmon, red snapper, swordfish, tuna, halibut, flounder)
- Garlic
- Some nuts (walnuts, Brazil nuts) and seeds (sunflower seeds)
- Grains
Side Effects
High doses of selenium (more than 400 micrograms) can cause:- Dizziness
- Nausea
- Fatigue
- Hair loss
- Tooth decay
- Kidney damage
- Liver damage
Potential Interactions and Warnings
Some antioxidants can stimulate the immune system. MS is an autoimmune disease, meaning that parts of the immune system are already too active. Therefore, it is theoretically possible that increasing immune activity by using antioxidants can stimulate MS disease activity. While this has not been seen directly, it is something to remember when considering antioxidant therapy.
Taking antioxidants in combination (selenium with vitamins C and E and beta-carotene) seems to decrease the effectiveness of niacin and simvastatin (Zocor). It is possible that this could also apply to atorvastatin (Lipitor), fluvastatin (Lescol), lovastatin (Mevacor), and pravastatin (Pravachol).
Price
The cost of supplemental selenium tablets is extremely low, usually less than 20 dollars per year.Other Uses of Selenium
In general, selenium is needed for the proper functioning of the immune system and for the production of prostaglandins, substances that reduce blood pressure and inflammation. Low levels of selenium may cause atherosclerosis (plaque buildup in arteries which can lead to heart attack and/or stroke) to worsen and can lead to premature aging. Selenium deficiencies have also been linked with certain types of cancer.Additional Information/Points
Antioxidants and the Blood-Brain Barrier: Some experts point out that in order for supplemental therapies to work directly to slow MS progression (as some people like to claim), they would need to cross the blood-brain barrier, which most antioxidants do not do in the case of an intact blood-brain barrier.
Glutathione Peroxidase and MS: Many of the benefits of selenium are related to its role in the production of the enzyme glutathione peroxidase, an enzyme responsible for detoxification in the body. People with MS tend to have lower levels of glutathione peroxidase, which have led some to speculate that people with MS have a problem metabolizing or using selenium to make this enzyme. However, studies have confirmed that that the reduced glutathione peroxidase activity found in red blood cells of people with MS is not related to the selenium concentration in their bodies, but probably due to genetic factors.
My Bottom Line
Am I going to take selenium? I probably won’t go out of my way to take a selenium supplement. However, I will take a multivitamin and mineral supplement that contains a moderate amount of selenium (as well as moderate amounts of other antioxidants).Sources:
Schwarz S, Leweling H. Multiple sclerosis and nutrition. Mult Scler. 2005 Feb;11(1):24-32.
Bowling, Allen C. Complementary and Alternative Medicine and Multiple Sclerosis. 2nd ed. Demos Publishing: New York. 2007.
Mazzellaa, GL, et al. Blood Cells Glutathione Peroxidase Activity and Selenium in Multiple Sclerosis. Eur Neurol. 1983;22:442-446.
MedlinePlus. Selenium. U.S. National Library of Medicine and National Institutes of Health.
