People have been searching for a miracle drug--a single compound that could cure all that ails us--for hundreds of years. And the search hasn't been terribly successful. But over the past decade or so, science may have gotten as close as it ever has to that ever-elusive miracle drug. Best of all, it's either free or pretty close to free. The name of this magical compound? Vitamin D.
What Happens When You Don't Get Enough
Insufficient levels of vitamin D in the blood are associated with a variety of negative health outcomes.
Irritable Bowel Syndrome (IBS) - Researchers at the University of Sheffield (in the UK), were doing a study of patients with IBS and found that 82 percent of them had "insufficient levels" of the vitamin. IBS affects about 10-15 percent of the population and can be debilitating to those who suffer with it. Low levels of vitamin D have been found in people suffering from other gastrointestinal conditions, including inflammatory bowel disease. "It was clear from our findings that many people with IBS should have their vitamin D levels tested," said Dr. Bernard Corfe, the study's lead researcher, in a university press release. "And the data suggests that they may benefit from supplementation with vitamin D."
Cognitive Decline - Researchers from Rutgers University and the University of California, Davis, studied nearly 400 people ages 60-90 and found that seniors who don't get enough vitamin D "experience more rapid cognitive decline over time" than those who do get enough. "[O]n average, people with low vitamin D declined two to three times as fast as those with adequate vitamin D," wrote Joshua Miller, one of the study's lead authors and a professor of nutritional science at Rutgers. Those findings held true regardless of race or ethnicity.
Macular Degeneration - Age-related macular degeneration (AMD) affects more than 10 million Americans and is the leading cause of legal blindness. Researchers at the University of Buffalo found that people who already have a high genetic risk of developing the disease and who have low levels of vitamin D are 6.7 times more likely to develop AMD than those with the same genetic risk and normal D levels.
Prostate Cancer - Men with low levels of vitamin D are four to five times more likely to develop aggressive prostate cancer than those with normal levels.
Other cancers - Patients with adequate levels of vitamin D when they're diagnosed with cancer are more likely to survive than those whose levels are insufficient.
Depression - Low D levels double your risk of being diagnosed with depression.
Cardiovascular Issues - Being deficient in vitamin D increases your risk of developing heart disease by more than 30 percent. It also increases your risk of having a heart attack or a stroke.
Erectile Dysfunction (ED) - Men with severe ED are more likely to have low levels of vitamin D than men with less-severe ED, according to a 2014 study published in the Journal of Sexual Medicine.
Flu and Pneumonia - Vitamin D plays a role in maintaining a strong immune system. The weaker your immune system, the more likely you are to come down with the flu or pneumonia.
Weak Bones - Vitamin D helps your body absorb calcium from the foods you eat. Inadequate levels are associated with weaker bones and related conditions such as osteoporosis and rickets.
After reading all this, you're probably tempted to rush out to the nearest CVS and buy up their entire supply of vitamin D supplements. Don't. While low levels are definitely associated with all of the health risks outlined above (and plenty more), they don't necessarily cause those problems.
Amy Millen, the lead researcher on the macular degeneration study, put it this way: "Our message is not that achieving really high levels of vitamin D are good for the eye, but that having deficient vitamin D levels may be unhealthy for your eyes." The difference between the two is subtle but very important.
So How Much Should You Get?
Recommendations from a variety of reliable sources put the amount of vitamin D we should consume at between 600 and 2000 international units (IU) per day. But those numbers aren't particularly helpful, since the only way to know for sure what your vitamin D levels are is to have a blood test. If your levels are low, your medical provider will tell you what you'll need to do to boost them. The simplest--and cheapest--way is to spend some time outside. Generally speaking, 10-15 minutes in the sun every day is usually enough. But just because going outside is simple, doesn't mean it's easy. Some of us worry about skin cancer risk and wear so much sunscreen that we don't get enough exposure to natural sunlight. You'll want to talk with your provider about whether the benefit of increased vitamin D intake will offset any skin cancer risk.
If sunlight isn't in the cards (because of cancer risk or if you live in a place where the sun isn't out much), there are other ways to increase your vitamin D intake. Many foods (milk, for instance) are fortified with vitamin D, and others (eggs, salmon, and other fatty fish) are naturally high in the vitamin.
And then, of course, there are supplements, usually in the form of capsules. As with all supplements, don't take any more than your provider recommends.