Are You Minding Your Vitamin D?
For years, experts have documented low or inadequate vitamin D levels among a majority of Americans. And that’s a problem, say some, because vitamin D is important for a broad range of health effects. Also called the sunshine vitamin, vitamin D is a hormone made in the body when sufficiently strong sunlight strikes bare skin. Just 10 to 15 minutes of summer sun, for instance, is enough to generate all the vitamin D you need in a day, in most of North America.
Vitamin D is also available in some foods, such as eggs, fortified dairy, and fish, and a few vegetable sources, such as kale or mushrooms. Still, studies have repeatedly shown that most of us are walking around with too little of this crucial hormone. And it’s costing us.
Two important new studies published this month conclude that higher vitamin D levels are protective against heart disease, cancer, and death from all causes. One study noted that supplemental vitamin D3 may also reduce the risk of diseases such as multiple sclerosis, autoimmune disorders (such as rheumatoid arthritis), and infections. These effects are under discussion, but vitamin D’s ability to protect against cardiovascular disease and cancer is now undeniable. Low vitamin D status is linked to a whopping 35% greater risk of dying from heart disease, and a 14% greater risk of dying from cancer.
To put things in perspective, consider this: Data gathered from more than one million people suggests that about 13% of all deaths in the United States are attributable to low vitamin D levels. Thirteen percent! That’s a lot of deaths in a country of more than 300 million people. Those deaths might have been prevented by boosting vitamin D levels, say researchers.
A second study concluded there is “suggestive evidence” that high vitamin D is linked to lower risks of various diseases, such as type 2 diabetes, depression, high blood pressure, low birth weight, stroke, heart disease, obesity, etc. These were meta-analyses; the kinds of ambitious studies that examine data generated by many different studies and draw overarching conclusions based on statistical analysis of their findings. Although the latter study did not go so far as to suggest supplementation, the implication is clear: Unless you’re certain that your own levels are high, it’s at least worth considering having your levels checked. If less than optimal, it’s worth considering boosting your vitamin D status. Supplemental vitamin D3 is inexpensive and widely available. And sunshine will soon be available for free in most of the country. (Spring is finally here!)
Fish such as tuna and salmon are good sources of lean protein, heart-healthy omega-3 fatty acids and dietary vitamin D. In any event, making sure your levels of vitamin D are adequate seems like a no-brainer if you’re interested in boosting your overall health and decreasing your chances of dying from heart disease or cancer.
Chowdhury R, et al. Vitamin D and risk of cause specific death: systematic review and meta-analysis of observational cohort and randomised intervention studies. BMJ 2014;348:g1903. Theodoratou E, et al. Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational studies and randomised trials. BMJ 2014;348:g2035