by M.D. William Davis
Health care professionals have long thought vitamin D’s sole purpose was preserving bone health. Not anymore.
As a practicing cardiologist and long-time advocate of self-empowering strategies to reduce the risk of heart disease, I am excited about a growing body of research indicating vitamin D may do more than just help prevent osteoporosis.
Plaque buildup in the heart
Current research supports the concept that vitamin D may play a role in reducing plaque buildup and the risk of coronary disease. It shows that vitamin D deficiency contributes to conditions such as high blood pressure, poor insulin sensitivity, inflammation and other processes that underlie heart disease.
Italian researchers determined that the greater the vitamin D deficiency, the more carotid atherosclerotic plaque was present. The study’s authors concluded that low blood levels of vitamin D were an independent and strong predictor of atherosclerosis.
More heart attacks in winter
Several studies have demonstrated the striking seasonal variation of heart attacks: more frequent in winter and fewer in summer. The data connects this phenomenon to vitamin D.
Several large studies involving tens of thousands of people, including 3,400 participants in the Third National Health and Nutrition Examination Survey (NHANES III), have confirmed that low blood levels of vitamin D are associated with a doubling or tripling of heart attack risk.
Vitamin D and blood pressure
Blood pressure (BP) shows a consistent seasonal variation: lower BP in summer, higher BP in winter, consistent with the BP-reducing effect of vitamin D. BP is reduced modestly through vitamin D’s suppression of the blood pressure-raising hormone, renin, an effect similar to the ACE inhibitor class of prescription medications.
Vitamin D is crucial for the prevention of osteoporosis and fractures. Vitamin D exerts a far more potent effect than calcium. Intestinal calcium absorption quadruples when vitamin D levels are brought to normal levels.
Several clinical trials demonstrate a reduced incidence of hip fracture in the elderly with vitamin D at low doses of 400-800 IU per day.
Counteracting insulin resistance
Among the most exciting effects of vitamin D supplementation is the body’s enhanced sensitivity to insulin, which counteracts the poor responsiveness seen in pre-diabetes and diabetes. A large European study of 7,500 people demonstrated 72% less likelihood of diabetes in people with higher blood levels of vitamin D.
Raising blood vitamin D levels to the normal range reduces blood sugar, which, in turn, raises HDL (good) cholesterol and reduces triglycerides.
Cancer of the colon, prostate, bladder and breast
Numerous recent studies have demonstrated that winter, less sun exposure and low blood vitamin D levels are all associated with increased likelihood of cancer. Several studies have also shown improved survival when vitamin D is added to cancer therapies, particularly with cancer of the colon, breast, bladder and prostate. The Women’s Health Initiative of 36,000 women showed that low vitamin D supplementation of 200 IU per day was insufficient to yield any difference in breast cancer incidence vs. placebo. Higher doses seem to be required for cancer-preventing effects. A prospective Creighton University study of 1,179 participants receiving 1,100 IU of vitamin D per day demonstrated 35% reduced risk of cancer for every 10 ng/mL increase in vitamin D blood levels. An Emory University study demonstrated that 800 IU of vitamin D per day reduced pre-cancerous changes in colon tissue after six months.
Studies suggest vitamin D may reduce cancer risk through its role in reducing cell proliferation (i.e., cell multiplication that leads to cancer growth) and inducing differentiation (to restore more normal cell characteristics).
Getting enough vitamin D
Severe vitamin D deficiency affects 50% or more adults. Since your skin can make vitamin D from sun exposure, in places where sun exposure is minimal, deficiency can be as high as 90%. The elderly are more prone to deficiency since the capacity to activate vitamin D in the skin is lost as we age. However, simply living in a sunny climate provides no guarantee against deficiency. Studies in south Florida and Hawaii have demonstrated surprising levels of deficiency.
Other factors that increase need for vitamin D include sunscreen use, having dark skin, living in the northern U.S. and being overweight.
When supplementing with vitamin D, D3 is the preferred form, since it is far better absorbed than D2. In northern climates or sun-deprived lifestyles, 2,000 IUs per day is a reasonable starting dose. It’s wise to not exceed 2,000 IUs per day, in agreement with the Institute of Medicine’s recommendation of a safe upper limit, unless instructed to do so by your doctor and based on your blood level.
My artery plaque reversal plan
My clinic follows a multi-faceted approach to reversing coronary plaque. First, we document the quantity of plaque through a CT heart scan. Then we correct problem cholesterol levels like low HDL and high cholesterol and triglycerides, preferably with minimum medication.
We recommend fish oil—providing a minimum of 1,800 mg of omega-3 fatty acids, EPA and DHA—every day.
For endothelial health, we suggest 3,000-6,000 mg of L-arginine twice per day.
Emerging data, such as the Rotterdam Heart Study, suggest that vitamin K2 deficiency may play an important role in allowing coronary atherosclerotic plaque to grow. We suggest 1,000 mcg of vitamin K2 (the MK-4 or MK-7 forms) per day.
Magnesium plays an important role as a cofactor for the enzymes that help modulate insulin responses, maintain triglycerides, HDL, inflammatory responses and blood sugar, and prevent muscle cramps and heart rhythm abnormalities. To help regulate these common contributors to coronary plaque growth, we suggest about 400 mg per day.
As healthy people minimize their use of iodized salt, we also urge our patients to consider an iodine supplement, such as kelp tablets, to provide iodine, 500 mcg per day. This is important to maintain thyroid health, and crucial to maintain control over cholesterol values and heart disease risk.
We use supplements to raise blood levels of vitamin D to 60-70 ng/mL (150-175 nmol/L). Most people in the northern U.S. require 4,000-6,000 IU or more per day in winter and slightly less in summer.
Using this approach, we now have an impressive track record of reducing CT heart scan scores. Reductions of 20-30% in the first year are not uncommon. Excerpt: https://www.nutritionexpress.com/showarticle.aspx?articleid=1181