This week I am continuing my coverage of “The Vitamin D
Solution” by Dr. Michael Holick.

One of the most interesting chapters of the book was the one in which he discussed
autoimmune diseases -especially multiple sclerosis and type 1 diabetes.

Multiple sclerosis (MS) is a disease in which cells ofthe immune system attack the
nerves, leading to loss of muscle coordination, weakness and even loss of sight.

MS generally develops in middle age and is much more prevalent in women than in men.
There is also a genetic component to MS, with people of Scandinavian or Celtic
origin being more prone to developing MS.

But by far the strongest predictor of MS risk is sun exposure. People in North
America or Europe are five times more likely to develop MS than people who live in
the tropics, Even in North America people living above the 37th parallel are twice
as likely to develop MS as people who live below the 37th parallel.

And the most interesting part of it is that the risk of developing MS seems to be
determined by your sun exposure at an early age. Once you’ve reached the age
of 15 you can move anywhere in the world and your risk of MS will not be altered.
It has already been determined by your sun exposure before the age of 15.

Type 1 diabetes is caused by the immune cells attacking the pancreas and rendering
it unable to make insulin.
Once again sun exposure seems to play a significant role. Northern Finland,
for example, has the world’s highest incidence of type 1 diabetes. Since type 1
diabetes generally develops during childhood, the question of whether you could
decrease the incidence of type 1 diabetes by getting more sun exposure after age
15 is a moot point.

The mechanism of this effect is not known, but it is known that the thymus plays
an important role in destroying immune cells that could harm the body. This
function of the thymus is particularly important when we are young and recent
research suggests that it could be regulated by vitamin D.

The evidence that vitamin D could prevent MS is indirect, but there is clinical
evidence that vitamin D can prevent type 1 diabetes.

The Finnish government did a major study with 12,000 children in 1966 in which
they gave half of them 2,000 IU of vitamin D/day during their first year of life and
the other half a placebo.

The children who received the vitamin D supplement during their first year of life
were 80% less likely to develop type 1 diabetes than those who received the
placebo. And when they did the comparison with a subgroup of children who were
demonstrably D deficient (they developed symptoms of rickets), the vitamin D
supplementation decreased the risk of developing type 1 diabetes by 2.4 fold (240%).

However, with both type 1 diabetes and MS it appears that the die is cast early in
life. Dr. Holick and others have tried vitamin D therapy with patients that
have already developed MS or type 1 diabetes without success.

So what is the bottom line?

If you have already developed MS or type 1 diabetes, there is no evidence that
vitamin D supplementation can slow or reverse the disease (although it may reduce the
risk of osteoporosis and many other diseases).

However, one of the greatest gifts that you can give your children may be to make
sure that they get adequate levels of vitamin D from birth through adolescence. And
that is particularly important in light of studies showing that 50 – 70% of our children
may not be getting enough vitamin D.