Vitamin D Patient Info Sheet

Vitamin D Supplementation

What is Vitamin D?

Vitamin D is a fat-soluble vitamin. It plays an important role in regulating calcium and phosphate in the body. This is important for bone health.

Where does Vitamin D come from?

Vitamin D comes from two sources, diet and sun exposure. The main dietary source is fish and fish oils. Meat, cheese and eggs contain smaller amounts of vitamin D. Milk and orange juice are often fortified with vitamin D to help with calcium absorption.

Sun exposure provides the largest source of vitamin D. Ultraviolet B (UVB) light produces vitamin D in the skin. 15-20 minutes of full body sun exposure produces 10,000 international units (IU) of vitamin D. Darker skin may require 5-10 times this long to get the same vitamin D production. Exposure limited to face and hands provides about 200-400 IU/d. Complete cloud cover reduces this by 50%. There is a maximum amount of vitamin D that can be made by skin in a day, and 10,000 IU/d (or lesser amounts for limited areas of skin exposure) cannot be exceeded by staying in the sun longer.

What is the link between Vitamin D and multiple sclerosis?

For more than 50 years, it has been recognized that multiple sclerosis is more common in northern locations. There have been many attempts to explain this distribution of the disease. One of the theories about what might cause multiple sclerosis is that people in the North have less vitamin D, which might cause or worsen the disease.

Do people with multiple sclerosis have low Vitamin D level?

As a group, people with multiple sclerosis have low vitamin D levels. However, not all people with multiple sclerosis have low vitamin D levels. Many people with multiple sclerosis have normal vitamin D levels, though the average for all people with multiple sclerosis is low.

Does this mean that low Vitamin D levels cause multiple sclerosis?

No. Though multiple sclerosis and low vitamin D levels tend to go together, it is not known whether the vitamin D contributed to the disease, whether the disease caused the low vitamin D levels, or whether some completely different factor caused both.

How might multiple sclerosis cause a low Vitamin D level?

Vitamin D is produced in the body by exposure to sunlight. Many people with multiple sclerosis are sensitive to the heat, and therefore they spend less time in the sun than normal people. This could lead to a low vitamin D level.

How might low Vitamin D cause or worsen multiple sclerosis?

Recently, vitamin D has been recognized to have effects on the immune system. Through these effects on the immune system, it might cause an increase in immune reactivity.

How might a completely different factor cause both?

There are many conditions that could contribute to both multiple sclerosis and a low vitamin D level. For example, some of the genes that control calcium and vitamin D metabolism also can affect the immune system.

Has Vitamin D been shown to alter the course of multiple sclerosis?

To date, studies have not been done to examine the effect of vitamin D on the development of multiple sclerosis, nor on the course of people who already have multiple sclerosis.

How is Vitamin D measured?

A blood test is used to measure vitamin D.

What is the normal level of Vitamin D?

Normal vitamin D levels are greater than 30ng/mL. However, in multiple sclerosis it is generally recommended that levels of about 100ng/mL be used.

Are there risks of taking Vitamin D?

Health risks from excessive Vitamin D are not usually seen at serum levels less than 200 ng/mL.
Too much vitamin D taken for long periods of time may lead to headaches, weight loss, and kidney stones, nausea, vomiting, anorexia/poor appetite, constipation, muscle weakness, and weight loss.

Vitamin D supplements have the potential to interact with several types of medications.

How can side effects be minimized?

Side effects can be minimized by checking vitamin D blood levels after starting the supplement, or after dosing changes. These levels should be checked 2-3 months after making a dose change.

Vitamin D availability

Over the counter vitamin D is available in several forms:
Vitamin D, 400, 700, 1000, 2000 IU tablets and capsules
Vitamin D + sesame oil 2000IU/drop (Biotics)