Memory and Vitamin D

Vitamin D is a hot topic lately.  One of the latest studies is called InCHIANTI, done it Italy (are you surprised?).  The study looked at people who were older with normal memories.  It checked their Vitamin D levels, and then watched over several years to see who got dementia.  Those people with low vitamin D levels were six times more likely to have memory problems… fascinating.    One of my buddies runs a nursing home and is on a big vitamin D checking spree.  She checks vitamin D levels on all her nursing home patients.  Almost all of them are low. 

So what is going on?  Some researches think that brains have to have vitamin D to work well.  Other researchers say that a low vitamin D level is a marker of low physical activity, poor mobility and higher amounts of fat.  The theory is that people who don’t go outside and exercise and are fatter have a lot more memory problems and health problems.  So it is like saying if you wear smaller shoes you will have small feet.  But what really happens is that only people with small feet wear small shoes.   Perhaps giving people vitamin D won’t make memory problems go away.  We know giving people small shoes won’t shrink their feet.  We don’t really know yet what happens when you give people vitamin D when their levels have been low.  That will be a great study when it comes out.

The new recommended daily amounts of vitamin D3 will probably be about 1200 IU to perhaps as high as 2000 IU.  This is much higher than the current amount of 400 IU daily.  It looks like this amount is quite safe.  It also looks like unless you are outside more than 3 hours a day, every day, there is a good chance your levels will be low.  This might be one of the few vitamins people need.

Archives of Internal Medicine 2010;170:1135-1141, 1099-1100