To find out whether a supplement will provide specific benefits, it is necessary to understand how the immune system works in MS and how a specific vitamin or mineral will impact the immune system. As MS is an autoimmune disease in which the immune system appears to be attacking the body and causing damage to the CNS, any supplement that claims to boost or improve the immune system should be avoided. Additionally, in evaluating vitamins and minerals for use as potential symptomatic and/or disease-modifying treatments, it is important to look at evidence for the effectiveness and safety of these substances.
Dosing is an important factor with vitamin or mineral supplements. Vitamins or minerals taken at a certain dose may be beneficial. However, taken at a higher dose, the same vitamin or mineral may be harmful. So, it is very important to work with your doctor and other members of your care team to determine which supplements you should take and what the proper dose should be.
Basics about vitamins and minerals
Vitamins are chemicals that our bodies need to maintain health. Except for vitamin D, which is a hormone produced in the skin when exposed to sun, we typically get our daily requirement of vitamins from dietary sources (foods and drinks). Vitamin D can also be obtained from some foods.
Minerals are inorganic substances. Like vitamins, our bodies need certain minerals to stay healthy and we can get these from dietary sources. The Food and Nutrition Board of the National Academy of Sciences has defined the recommended daily allowance (RDA) of different vitamins and minerals that we need to consume on a daily basis. There is general agreement that we should get the RDA of basic vitamins and minerals to stay healthy. There is controversy, however, about whether we should take more than the RDA of certain vitamins and minerals. It is understood that getting too much of some vitamins and minerals may be dangerous to health. This is why it’s important to talk to your doctor before you take any vitamin or mineral supplement (or any other type of supplement).
Vitamins and minerals in MS
A variety of vitamins, minerals, and other related supplements have been evaluated for use as symptomatic and disease-modifying treatments for people with MS. The most important of these include vitamin D and vitamins and minerals with antioxidant effects, such as vitamins C and E and selenium.
Vitamin D supplements are potentially important for people with MS from both the perspective of symptom management and disease-modifying effects. Vitamin D is recognized as an important factor in maintaining bone density and people with MS are at increased risk for bone loss (osteopenia and osteopororsis) for many reasons, including corticosteroid use, decreased sun exposure, and loss of mobility.
Results from several studies suggest that increased blood levels of vitamin D (as well as high intake of the vitamin) may be associated with a decreased likelihood of developing MS and a decreased risk of exacerbations and disability progression in people with MS. More studies are needed to determine a clear relationship between vitamin D and MS and for more definitive evidence as to whether vitamin D supplementation truly has disease-modifying effects. Albeit, people with MS may choose to take vitamin D supplements at modest amounts of 1,000 to 2,000 international units (IU) daily. The generally accepted safe upper limit for daily vitamin D intake is 4,000 IU, however higher amounts may be recommended based on your specific circumstances.. If you would like to use vitamin D supplements, talk to your doctor first. Your doctor can give you a blood test to find out your blood level of vitamin D and, if it’s below normal, your doctor may suggest a daily supplement amount to bring your levels up to normal.
The idea behind taking antioxidant vitamins, which include vitamin A (usually taken as beta-carotene, which is a safer form of the vitamin), and vitamins C and E, is that these vitamins reduce damage caused by free radicals. A free radical (also called an oxidant) is a molecule in the body that has an unpaired electron. These molecules are very unstable because they are constantly trying to pair their unpaired electron. This causes them to react with other substances in the body, resulting in oxidative damage. The RDA of antioxidant vitamins can be obtained by eating 3 to 4 servings of vegetables and 2 to 4 servings of fruits every day. The safety of taking antioxidant vitamin supplements in amounts exceeding the RDA has not been established in people with MS and there is a theoretical risk that these vitamins may stimulate the immune system, which is already overactive in MS.
Vitamins C and E, in combination with selenium, have been tested in a small study conducted in people with MS. Although the combination was well tolerated, the study was too small to make any determination about effectiveness.
It is also thought that vitamin C may be useful in helping prevent urinary tract infections, which can occur commonly in people with MS. The idea behind this is that vitamin C may help to make urine more acidic, which in turn makes it more difficult for bacteria to colonize the urinary tract. However, evidence indicates that vitamin C does not acidify urine. Therefore, there is some controversy about whether intake of high amounts of vitamin C is beneficial for a person with MS. Evidence does support the use of cranberry (in pill or juice form) to acidify urine and protect against urinary tract infections.
Vitamin E, which is available in vegetables, nuts, meats, vegetable oils, and fruits, prevents oxidative damage in the body. If you are taking polyunsaturated fatty acid (PUFA) supplements or consume a diet high in PUFA, which is thought to be beneficial in MS, your requirements for vitamin E will go up. Before you start increasing PUFA intake, talk to your doctor about how this will increase your need for vitamin E.
Vitamin A is an important vitamin for eye health as well as normal cell growth throughout the body. Sources of vitamin A include liver, eggs, and cod liver oil. Vitamin A is a fat soluble vitamin which is stored in the body and may accumulate over time. Therefore, you should avoid taking too much of this vitamin. The RDA for men and women ranges from 2,300 to 3,000 international units (IU) and daily intake should not exceed 10,000 IU. If you are pregnant, you should not consume high amounts of vitamin A because intake of excessive amounts of this vitamin may result in birth defects. Pregnant women should limit vitamin A intake to the safer form of the vitamin found in fruits and vegetables called beta-carotene.
B complex vitamins, which contain vitamin B6 (pyridoxine), are taken to increase energy. Natural sources of vitamin B6 include many different foods, such as fish (salmon and tuna), vegetables, chicken and pork, beans, and bananas. The RDA for vitamin B6 is 1.3 milligrams for adults ages 19-50 years and high amounts of the vitamin (such as 1,000 milligrams) can cause numbness, tingling, or pain. These symptoms are reversible once supplementation is decreased.
Claims have been made that vitamin B12 (cobalamin) is an effective treatment for MS. However, there is little evidence to support these claims. Deficiencies in vitamin B12, which can lead to MS-like neurological symptoms, are typically found in only a small number of people with MS. In patients who have low levels of vitamin B12, a supplement should be used. Natural sources for vitamin B12 include meat, poultry, shellfish, eggs, and dairy products.
The mineral selenium has antioxidant effects and sources include legumes, seafood, whole grains, lean meats, and dairy products. Supplementation of the mineral selenium is potentially useful in MS because of the antioxidant properties of this substance. Selenium is contained in antioxidant enzymes (thioredoxin reductase and glutathione peroxidase) which are active in reducing certain oxidized molecules in the body. Selenium (in combination with vitamins C and E) was tested in a small study conducted in people with MS. Although the combination was well tolerated, the study was too small to make any determination about effectiveness.
Adequate intake of calcium, which is the most abundant mineral in the body, is important to maintain the health of bones and teeth, and the regulation of vital body processes. An old hypothesis that high calcium intake (consumption of large amounts of milk or other dairy products) during childhood, with a sudden decrease in consumption at adolescence, can cause MS is not supported by much evidence. Dietary sources of calcium include dairy products, leafy vegetables, and eggs. People with MS are at increased risk for bone loss, so adequate calcium intake is crucial (RDA for adults: 1,000 to 1,200 milligrams). Calcium taken in excess amounts may result in toxic effects. To avoid this risk, calcium intake should not exceed 2,000 milligrams per day for those over 50 years of age and 2,500 milligrams for those 19 to 50 years of age.
Zinc is used in many different processes in the body (RDA for men: 11 mg; women: 8 mg). There have been few systematic studies of zinc in MS. Results from some studies have shown that people with MS have low levels of zinc, while other studies have shown the opposite. These latter studies have suggested that zinc may work to activate the immune system and that zinc supplementation may worsen MS. High intake of zinc can result in copper deficiency, which may result in MS-like neurologic symptoms.