You may remember the vitamin D craze of a few years ago. Because enthusiasm for the therapeutic benefits of this vitamin has simmered, some people might be tempted to believe that it was just a fad. But nothing could be farther from the truth.
Vitamin D is essential for nearly every aspect of your health—and the problem of deficiency is still as widespread as ever.
According to a 2011 study, 41.6% of all Americans, and approximately 1 billion people worldwide, are deficient in vitamin D. The number skyrockets among some minorities in the United States: 69.2% of Hispanics and 82.1% of African Americans are deficient.[1]
This is bad news, because sufficient vitamin D levels are necessary for a wide variety of bodily functions. It’s so important that every cell in your body has a receptor for vitamin D. “Vitamin” is actually somewhat of a misnomer, because it functions as a hormone—and contrary to what we used to believe about it, vitamin D doesn’t just build strong bones (though that’s certainly one of its many benefits).
Beisdes regulating levels of phosphorus and calcium in the blood (which is how it contributes to skeletal strength and stability), vitamin D also optimizes immune function,[2] regulates mood,[3] promotes cardiovascular health, and much more.[4]
Vitamin D deficiency has been correlated with a staggering list of diseases and conditions, including heart disease, type 1 and type 2 diabetes, Crohn’s disease and other gastrointestinal issues, Alzheimer’s disease and general cognitive decline, greater incidence of infectious illness, multiple sclerosis, hypertension, stroke, and cancer.[5]
And sadly, many people don’t even know they’re deficient until they’ve developed more serious health issues. Luckily, there are some signs you can look out for.
Common symptoms of deficiency
First and foremost, it’s important to note that some people are more predisposed than others to vitamin D deficiency. As indicated above, those with darker skin tend to be more at risk, as do the elderly, vegetarians, those who are overweight or obese, and those who live far from the equator. If you fit into any of these categories, you should pay especially close attention to your vitamin D levels.
Here’s some other signs that it could be time to get your vitamin D levels tested.
Bone loss is perhaps the most obvious symptom, given that vitamin D is thought to be predominantly associated with skeletal health. A large observational study found a strong correlation between low vitamin D levels and low bone density.[6]
Frequent illness. As mentioned above, vitamin D plays a critical role in the functioning of the immune system.[7] Observational studies demonstrate that those who frequently contract colds, flus, brochitis, and pneumonia are vitamin D deficient,[8] and that supplementing with 4,000 IU of vitamin D daily may reduce the risk of respiratory infection.[9]
Depression. While it’s hard to say whether vitamin D deficiency is an actual causative factor in clinical depression, any consistently low or depressed mood can be a sign that you’re deficient. Researchers have linked vitamin D deficiency with depression, especially in older adults.[10]
Fatigue. When tiredness and fatigue becomes chronic and consistent (whether it’s caused by insufficient sleep and excess work or not), it is nearly always correlated with low levels of vitamin D,[11] which your body recruits in order to deal with its burden of stress. Studies demonstrate that such fatigue can be overcome through vitamin D supplementation.[12]
Back pain. If you suffer from chronic lower back pain—particularly the kind that can’t be traced to a specific injury—it could be a sign of vitamin D deficiency. Research has shown time and time again that those with deficiencies are much more likely to have moderate to severe back pain.[13]
How to restore optimal vitamin D levels
If you’re suffering from any of these symptoms, get your vitamin D levels tested as soon as possible. Don’t put it off; vitamin D deficiency is very simple to fix, but can have disastrous consequences for your health if left unaddressed.
If your blood serum levels are below 40 ng/ml, it’s time to make some lifestyle changes, and possibly to begin a supplementation regimen. Start by spending more time outside—about twenty minutes every day in direct sunlight, with as much of your body exposed as possible, will work wonders.
If you live in a latitude above 37 degrees north, however, your skin won’t make enough vitamin D when exposed to the sun throughout the majority of the year. Take a look at this map to locate your “vitamin D latitude”:
If you live above the red line, it’s particularly important that you get your vitamin D from food and supplements. Eat plenty of fish, orange juice, milk (preferably raw), egg yolks, and fortified cereals, and take a high-quality, high-bioavailability vitamin D supplement daily.
Seek out liposomal vitamin D if possible, and always take D3 instead of other forms. For best results, combine your vitamin D with MK-7, a form of vitamin K2 that works synergistically with it.
References
[1] https://www.ncbi.nlm.nih.gov/pubmed/21310306
[2] https://www.ncbi.nlm.nih.gov/pubmed/20824663
[3] https://www.ncbi.nlm.nih.gov/pubmed/26998791
[4] https://www.hsph.harvard.edu/nutritionsource/vitamin-d/
[5] http://www.nejm.org/doi/full/10.1056/NEJMra070553
[6] https://www.ncbi.nlm.nih.gov/pubmed/26538987
[7] https://www.ncbi.nlm.nih.gov/pubmed/20824663
[8] https://www.ncbi.nlm.nih.gov/pubmed/27178217
[9] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3686844/
[10] https://www.ncbi.nlm.nih.gov/pubmed/26998791
[11] https://www.ncbi.nlm.nih.gov/pubmed/26543719
[12] https://www.ncbi.nlm.nih.gov/pubmed/21206551
