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Vitamin D, Biotin & Omega-3

Dietary Studies in MS

Researchers are beginning to make significant connections around diet and MS.

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In this article

Vitamin D

Vitamin D is a hormone and has many functions in the body:

  • promotes the absorption of calcium, necessary for bone health
  • supports immune response to infections
  • helps to limit inflammation and regulate the immune system
Low Vitamin D is common and deficiency of Vitamin D (very low levels in the blood) may cause thin bones and increase the risk for fractures. Low Vitamin D may cause muscle weakness and a deficiency may increase your risk for certain types of cancer, heart disease and even mood disorders. 

Several epidemiological studies (studies of populations) have shown that low Vitamin D is one of several risk factors that can contribute to the development of MS. Other studies have suggested that low Vitamin D may be associated with more MS activity.  However, it has not been established that correcting low Vitamin D impacts the MS disease course. Vitamin D and MS continues to be an active area of research.

Our best source of Vitamin D is sun exposure (about 15 minutes/day) – which allows our body to make its own Vitamin D by absorption through the skin. But with less time in the sun due to skin cancer risk, and the use of sunscreens, sun exposure is often limited. Also, for some, heat exposure can temporarily make MS symptoms feel worse. Food sources of Vitamin D include oily fish (such as salmon or tuna), beef liver, egg yolks, pork, fortified foods such as milk and juices. It is difficult to get sufficient Vitamin D from food, so most people who have low Vitamin D take a supplement.

It is possible to get too much Vitamin D from supplements, and too much can cause side effects – such as kidney stones, kidney failure, bone loss, fatigue, dizziness, confusion, vomiting and nausea. Your supplement dose needs to be individualized and ideally based upon your blood level of Vitamin D. Work with your MS provider or your primary care provider to determine the dose that you should take.


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Vitamin D and MS

Research into the role Vitamin D plays in MS is growing.


Biotin is considered a form of vitamin B, and is a component of enzymes in the body that help break down certain substances. It also activates certain enzymes that help the body produce myelin – the substance wrapped around many nerves in the central nervous system. Biotin, also known as vitamin H, is usually obtained from food.

Because of the role in myelin production, high-dose Biotin (MD1003) was thought to be a promising treatment for progressive MS and early clinical trials had positive results. However, the largest clinical trial of MD1003 involving people with primary and secondary progressive MS who did not have recent relapses failed to reverse disability or improve walking speed in those who took MD1003 versus placebo. The study authors reported treatment with MD1003 led to inaccurate laboratory tests for other health conditions and that commercially available high-dose biotin should not be used to treat progressive MS.

NOTE: In November 2017, the US Food and Drug Administration (FDA) issued a Safety Communication to let the public and healthcare providers know that biotin can significantly interfere with certain lab tests, causing falsely high or falsely low test results that may go undetected. They issued a second Safety Communication in November 2019 to remind the public and healthcare providers about biotin interference with lab tests. Work with your healthcare provider and laboratory to help prevent adverse events. If you suspect or experience a problem with a laboratory test while taking biotin, the FDA encourages you to report the problem through the MedWatch Voluntary Reporting Form.


Fat is an essential nutrient for the body. While some fats are deemed “bad,” others, such as polyunsaturated fats, actually help lower cholesterol and the risk of heart disease. These polyunsaturated fats — and the omega-3 fatty acids they contain — have been the focus of MS studies with some evidence pointing to benefits for relapsing-remitting MS.

Fishy benefits?

Two placebo-controlled clinical trials studied supplementation with omega-3 fatty acids. A large, two-year study followed 312 people with MS. The group taking daily 10 grams of fish oil (which contains omega-3 fatty acids) had less disability progression and fewer relapses than those taking the “dummy pill.” The difference was not “statistically significant,” but there was a trend favoring the fish oil group.

Getting a dose

  • Omega-3 fatty acids are found in certain fatty fish, such as salmon, mackerel, herring and sardines, and in fish oil products.
  • Smaller amounts are found in a few other sources, such as canola oil, flaxseed, and walnuts.
  • Fish oil supplements, in pill or liquid form, are the richest sources of omega-3 fatty acids. A daily intake of up to 3 grams is usually considered safe.

The cautions

  • The safety and effectiveness of omega-3 supplementation in combination with Copaxone®, Avonex®, Betaseron®, or Rebif® have received only limited study. It is possible, though unlikely based on current evidence, that omega-3 fatty acid supplements could decrease their effectiveness. Omega-3 fatty acids have not been studied with Novantrone® or Tysabri®.
  • Drug interactions may occur with anticoagulant medications such as warfarin (Coumadin®), enoxaparin (Lovenox®), heparin, aspirin, and other drugs with aspirin-like effects such as clopidine (Ticlid®) and clopidogrel (Plavix®).
  • Omega-3 fatty acids may also decrease the effectiveness of insulin, oral diabetes medicine, and high blood pressure medications.

To take or not to take?

Reasonable doses of fish oil supplements are generally safe as long as there are no medical issues restricting its use (see cautions above). While there is a scientific rationale for taking omega-3 fatty acids and some hints of effectiveness, omega-3 fatty acids should never be used instead of the conventional MS medications or treatments. If one is considering taking omega-3 fatty acids, this decision should be discussed with a health professional.


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