You probably know vitamin D as “the sunshine vitamin,” as our bodies make it when our skin is exposed to sunlight. Surprisingly, though, vitamin D deficiency is actually pretty common. A 2011 study found that 41% of US adults don’t have enough of the vitamin in their blood.
Vitamin D actually works in the body like a hormone and unlike other vitamins, every cell in the human body has a receptor for it. It’s vital for bone health and immune function. In fact, maintaining proper levels might be beneficial in warding off heart disease and certain types of cancer.
Here are a few subtle signs that you have a vitamin D deficiency.
It took you forever to get over your last cold.
One of the most important roles vitamin D plays is keeping your immune system in top condition. When you’re deficient in this key vitamin, it might take you longer to get over minor infections and viruses.
You’ve been feeling down or depressed.
Depression and low mood can be related to a number of physiological and psychological factors. However, there is scientific evidence that links a vitamin D deficiency to depression, especially in older people.
One study found that women given vitamin D supplements during the winter reported decreased symptoms of depression, while another study found a connection between symptoms of depression and low vitamin D levels in obese patients.
Depression is a complex mental health issue that is best treated with the help of medical professionals, but research suggests that taking a vitamin D supplement might be a helpful tool in staving off the blues.
You’re constantly tired even though you’re getting enough sleep.
Fatigue and tiredness can have a number of causes, but a vitamin D deficiency is definitely one of them.
Though multiple studies have found that having extremely low levels of vitamin D can induce symptoms such as chronic fatigue and headaches, even being slightly deficient has been shown to lead to feelings of tiredness and low energy.
After observing 200 female nurses, many of whom complained of fatigue, one study found that 89% of the nurses were actually deficient in vitamin D.
You have an achy back.
Vitamin D is incredibly important to bone health, as it helps your body absorb calcium and build a strong skeletal system. When you’re deficient, you’re more likely to have bone problems and an aching back.
One study of more than 9,000 older women found that there was an association between low vitamin D levels and chronic lower back pain. Some of the women with very low levels of vitamin D even experienced severe back pain that limited their ability to do daily tasks.
Your joints are more sore than usual after hitting the gym.
Just as low levels of vitamin D can lead to lower back pain, being deficient in this important vitamin can impact the health of bones and joints throughout your body.
Joints such as your knees, hips, and vertebrae are especially prone to problems if you have chronically low levels of vitamin D, so talk to your doctor about any aches and pains you think might be related to a vitamin D deficiency.
Your muscles seem shaky or painful.
There is some evidence that vitamin D deficiency might be one potential cause of muscle weakness and muscle pain.
Vitamin D plays a part in the health of nerve cells called nociceptors, which relay pain to the brain. Though muscle problems can have a range of causes, one study found that 71% of participants with chronic muscle pain were found to the deficient in vitamin D.
Another study found that taking high doses of vitamin D might help to lessen pain in people with low levels of the vitamin.
Talking to your doctor is the first step in diagnosing muscle pain, but it’s always a good idea to make sure your vitamin levels are in a health range.
Your hair seems thinner or more brittle than usual.
If you’re noticing that your hair isn’t as thick and lush as normal, you might want to look into upping your intake of vitamin D.
Though research into the effects of vitamin D on hair loss isn’t very robust, one study did find a connection between low vitamin D levels and hair loss in women.
Very low levels of vitamin D can also lead to rickets, which is a disease that causes soft and brittle bones in children. Rickets is sometimes associated with a hair loss disorder called alopecia areata. However, it’s very unlikely that a healthy adult will develop alopecia areata from low levels of vitamin D.
Your cuts or bruises take forever to heal.
Does it seem like every minor bump or scrape has you going through boxes of bandages? Impaired wound healing can be a sign that you’re deficient in vitamin D.
Some studies have found that the sunshine vitamin might actually increase production of compounds that are important to the process of forming new skin. There’s also some evidence that vitamin D could help control inflammation and fight infection. If you’re severely deficient in vitamin D, you might also have a harder time recovering from surgery.
You’re not getting enough sunshine.
If your daily routine typically involves going straight from your house to your car, to your office and back again, you might not be spending enough time outside for your skin to make enough the vitamin D to satisfy your body’s needs.
According to the National Institutes of Health, most people need about 600 IU of vitamin D daily. Though you can get vitamin D2 from foods like dairy, egg yolk, beef liver, and fatty fish, most people who don’t spend at least 30 minutes twice a week outdoors without sun protection aren’t making enough vitamin D to support their health. Taking a supplement is a good way to maintain healthy levels.
Further, although wearing sunscreen regularly is a great healthy habit that will help protect you from potentially cancer-causing overexposure to UVA and UVB rays, it can also limit your body’s ability to make its own vitamin D.
You’re having trouble getting or maintaining an erection.
According to one small study published in the Journal of Sexual Medicine, men with severe erectile dysfunction (ED) had much lower vitamin D levels than men with mild ED.
Researchers suggested that a lack of vitamin D might affect a man’s arteries, making them less able to dilate and fill the penis with blood. More research is needed to confirm a link between erectile dysfunction and vitamin D deficiency, but it may be something to bring up with your doctor if you’re experiencing problems with sexual performance.
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