If you think you know everything you need to know about vitamin D, think again.
In fact, the very act of thinking may be more influenced by vitamin D than we previously realized.
Let me explain.
There’s no question that vitamin D plays a critical role in the health of your bones. In fact, low levels of this hormone-like vitamin can actually cause osteomalacia, a disorder of impaired bone mineralization. And a flood of recent research has shown that low levels of vitamin D are associated with significantly increased risk for a wide range of diseases including cancer, vascular disease, infectious conditions, autoimmune disease, osteoporosis, mood disorders, type 2 Diabetes and even obesity!
Now get ready for another claim for this magnificently important vitamin: brain health.
Researchers writing in the Archives of Internal Medicine wanted to know if there was any relationship between low levels of vitamin D in the blood and any increased risk of substantial cognitive decline or dementia, an association that had not yet been fully investigated.
They looked at 858 adults 65 years or older and assessed their cognitive performance using a standard test called the MMSE (Mini-Mental State Examination) as well as two other widely used assessment techniques. The tests assess the ability to plan and organize as well as attention and overall cognitive skill.
The results were dramatic.
Compared to those who had sufficient levels of vitamin D in their bloodstream, those who were deficient (levels of <25 nmol/L) were found to have a whopping 60% greater risk of substantial cognitive decline on the MMSE (and about a 30% greater risk of cognitive decline using one of the other assessment tools).
“Low levels of vitamin D were associated with substantial cognitive decline in the elderly population studied over a 6-year period, which raises important new possibilities for treatment and prevention”, concluded the researchers.
I now consider vitamin D- along with omega-3 fatty acids- to be among the most important supplements to take on a daily basis. Best of all, vitamin D is one of the most inexpensive, readily available and easy to take (the pill form is the size of a tic-tac and there’s now a terrific emulsion formula that gives you 2000 IUs per drop(!) and that you can add to any drink).
Apparently I’m not alone. Just last month new updated guidelines on recommended vitamin D intake were published in the online issue of the Canadian Medical Association Journal. The new guidelines recommend daily supplements of 400 to 1000 IUs for adults under 50 without osteoporosis or conditions affecting vitamin D absorption. For adults over 50, supplements between 800 and 2,000 IUs are now recommended.
I think they’re being overly cautious, as conventional medical organizations tend to be. I personally take 8,000 IUs daily (8 drops of the emulsion or 4 “tic-tac” size gels) every single day. At that level there’s no known level of toxicity (your body can easily make 10,000 IUs when you spend a couple hours in the sun), and the benefit list seems to grow longer every single day.
{ 6 comments… read them below or add one }
Hello,
There is a simple formula offered by Dr. Robert Heaney as to daily need of vitmin D in international units (iu)
75iu/kg/d
This translates to 75 iu of vitamin D3, per kilogram of body weight, daily.
Vitamin D is not a static number, it varies based on a number of criteria.
So far this is the best personal formula out there. After 90 days have serum levels of vitmain D tested and adjust to stay in the target range of 40-60 ng/ml. As your weight changes you need to adjust your daily vitamin D.
I would respectfully add that in the opinion of most vitamin D experts I respect, 40 is way too low for optimal levels. I’d prefer to see 60-75, 80
Nonetheless by that formula, 75 iu per kg of body weight translates to ABOUT 5000 IUs a day for a 150 pound person, not a bad target, though I personally take more.
warmly
jb
I hear so much good about vitamin D and people that are taking large amounts, but I seem to be different that the norm, as I have to be careful how much I take. If I don’t take enough I don’t get much sleep and the same if I take too much I don’t sleep and lay awake most of the night.
Dr. Jonny,
In light of the talk on vitamin D, it would be interesting to see a future posts on your thoughts about current “best practice”/evidence-informed guidelines for K2 intake, either through food (particularly challenging in this day and age) or supplemental sources.
Thank you for all of the wonderful information that you so graciously share.
Jonny:
I take one drop of the emulsified vitamin D in my green drink every morning. I also put a drop in my wife’s protein drink, and in my 8 & 9 year old’s Omega Swirl. Should I increase those? I am a type 2 diabetic, by the way.
You should be fine with the 2,000 IUs daily. I personally take more, but even 2,000 IUs puts you well ahead of what most folks are getting. (Personally I’d go with 2 drops)
warmly
jb
{ 1 trackback }