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What Using Vitamin D Every Day Does to Your Body

Learn the signs of a vitamin D deficiency and what taking a supplement can do. 
FACT CHECKED BY Emilia Paluszek

Vitamin D is an essential nutrient our bodies need to help absorb calcium and maintain healthy bones. While it's not naturally found in many foods, you can get it from salmon, sardines, fortified milk and cereal. In addition, your body makes vitamin D when you're exposed to direct sunlight because it converts a chemical in your skin into an active form of the vitamin. That said, vitamin D deficiency is a frequent health issue many face due to certain medical conditions like Crohn's disease, which make it difficult to absorb vitamin D or other reasons and according to the Cleveland Clinic, "Vitamin D deficiency is a common global issue. About 1 billion people worldwide have vitamin D deficiency, while 50% of the population has vitamin D insufficiency. Approximately 35% of adults in the United States have vitamin D deficiency." As a result, many turn to supplements and Eat This, Not That! Health spoke with experts who share what to expect when taking vitamin D daily. As always, please consult with your physician for medical advice and before taking supplements. Many can have adverse interactions with certain medications and cause harmful side effects. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Signs of a Vitamin D Deficiency

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Shutterstock / Maridav

Lisa Richards, a nutritionist and author of the Candida Diet explains, "Signs and symptoms of a vitamin D deficiency can easily be passed off as just a side effect of your busy and exhausting lifestyle. But, chronic fatigue and other symptoms can be signs of a serious vitamin D deficiency. Other surprising signs of vitamin D deficiency include hair loss, muscle pain, and depression."


Boosts Your Energy Levels

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Trista Best, MPH, RD, LD says, "Taking vitamin D daily can boost your immune health and energy. Supplementing with vitamin D can be beneficial, especially for those with a known deficiency, because it can be difficult to get in through the diet. Some vitamin D deficiency symptoms are commonly confused for symptoms of other conditions. The chronic fatigue associated with vitamin D may also be confused with the tiredness associated with aging or typical life stress." 


Helps Strengthen Your Bones

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Richards states, "Vitamin D is essential to allowing your body to use the calcium it is given to support bone growth and health. When vitamin D levels are low this process is not as efficient and our bones can become weak. While we may not notice this initially, the side effects of our chronic vitamin D deficiency may show up later in life through fragile bones."


Offers Immune Support

According to Richards, "Vitamin D is becoming popular because of its immune support benefits that have been observed. The active form of vitamin D will help to mitigate the body's inflammatory response and boosts the body's immune cell production."


Provides Relief from Fatigue

Best tells us, "The relief one feels from their fatigue once they correct a vitamin D deficiency is surprisingly significant. If you have chronic fatigue, muscle weakness, mood disorders, and/or bone weakness you may be experiencing a vitamin D deficiency."


Vitamin D Can Have Harmful Side Effects


According to Best, "Because vitamin D is a fat soluble vitamin it is possible to reach toxic levels of this vitamin when taking it in supplement form. The side effects are relatively mild at first and include nausea, vomiting, frequent urination, and kidney issues. However, it can lead to more serious effects like poor bone and kidney stones. Vitamin D is a nutrient responsible for increasing calcium, phosphate, and magnesium absorption. The average individual needs between 400 and 4000 IU's a day." 

Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. Heather currently freelances for several publications. Read more about Heather