Vitamin D: Yes, But…
A year and a half ago I wrote in this space about getting vitamin D safely from the sun and now we need to talk about getting vitamin D safely without the sun! I’m writing this column on the shortest and darkest day of the year. When there is mid-day sun, I cast a shadow that seems ten feet tall! If you read the earlier column, you might remember the special tip about sunlight’s ability to help with vitamin D. Sunlight only encourages our skin to produce vitamin D when the sun is high enough in the sky so that the shadow you cast is shorter than you are. If I could stand the cold, I could stand naked for hours at mid-day without getting a tan, a sunburn, or any vitamin D.
Vitamin D: Yes….. Vitamin D has a function in almost every cell in the body. Most famously, adequate vitamin D levels help our bodies absorb calcium that we need to keep our bones healthy. While that function of D is well understood, we suspect many other functions that we can only begin to understand. Women with higher vitamin D levels have a lower risk of cancer. Adequate vitamin D is associated with a reduced risk of Alzheimer’s disease. Treating chronic pain patients with vitamin D reduces their need for pain medication. Folks with adequate vitamin D are less at risk for multiple sclerosis and other auto-immune diseases, though there’s no good evidence that after-the-fact supplementation can reverse the disease.
I’ve been checking vitamin D levels in my practice for about 20 years and most folks at this latitude need to supplement with 4000 i.u. daily of vitamin D3, taken as liquid rather than as capsules. The liquid should be taken directly or dropped onto food that’s heading for your mouth. An optimal level of 40-65 ng/mL is what folks living at the equator seem to achieve naturally if they spend a moderate amount of time outside, and that seems to be a good level for general health. The conventionally recommended dose (600 i.u.) has been inadequate in all but one person I’ve tested over 20 years. (I imagine folks living in Hawaii or Los Angeles need less: they get more days of overhead sun per year than Oregonians!)
You can get some vitamin D from fatty fish or from the lard of pasture-raised (sun-exposed) pigs, but you’d have to eat multiple servings daily to reach adequate levels. Different people’s ability to produce and maintain vitamin D levels varies considerably. Ideally: test your levels with a 25(OH)D test twice annually and adjust your intake as needed. Second choice: go with the 4000 i.u. You’re still more likely to under-dose rather than over-dose. Documented over-dose cases are both exceedingly rare and not surprising, usually occurring after months of excessively high daily doses of 20-40,000 i.u.
Yes, …but! There are two cautions with taking vitamin D regularly, and they both concern vitamin D’s ability to increase calcium absorption. With optimal vitamin D levels you will absorb plenty of calcium from a well-balanced diet. There is no need and may be harm in supplementing with calcium beyond the amount in a good multi-vitamin. The risk of excess calcium is that it deposits in places other than bone: the arteries of your heart, the blood vessels of your brain, and perhaps your inflamed tendons. So the second caution is that when you are taking vitamin D, you would be wise to also take vitamin K2 which directs calcium to the bones and keeps it away from other parts of the body that are better off without calcium deposits. A good form of vitamin K2 would be daily doses of fermented foods (kraut from the refrigerator section or cheese) or vitamin K2 as MK7, 100-200 mcg daily. Folks taking the drug Coumadin need to discuss vitamin K2 with their doctors as they need to be monitored.
So yes on vitamin D drops, but no on calcium, and particularly important if you are boosting D (and thus calcium absorption) get some vitamin K2 from either food or supplement.
Read more of Dr. Deborah’s healthy insights at www.DrDeborahMD.com.