Vitamin D is often called the "sunshine vitamin" because the body can naturally create it in the skin when exposed to sunlight. This type is called vitamin D3, as opposed to vitamin D, which naturally occurs in some plants, animals, and fungi. Despite the supposed ease of absorbing this vitamin, medical experts estimate about one billion people have vitamin D3 deficiencies. These can develop if a person is not getting outside enough, wears sunblock too often, has more melanin in their skin (darker skin acts as a sun blocker), eats a vegan diet or has milk allergies, or has an underlying condition that causes malabsorption. A variety of symptoms can indicate a vitamin D3 deficiency.



If you're low in vitamin D3, you may feel tired all the time and fatigued even when you're getting a good night's sleep. You may feel like you don't have the energy to keep up with everyday things. Vitamin D3 helps keep the body energized because it works toward good health in so many ways, including keeping the immune system healthy and enabling healing. Several research studies found a correlation between vitamin D deficiency and excessive fatigue. Furthermore, supplementation with vitamin D3 helped improve energy levels.

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Those who have low vitamin D3 are at a greater risk of catching colds and developing infections because the vitamin is essential for keeping the immune system strong and capable of fighting off infections.Colds, the flu, and several bacterial infections have been linked with vitamin D deficiency. Likewise, if you get infections frequently, you may have low vitamin D3 and should ask a doctor about having your levels checked.

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Back Pain and Bone Pain

Vitamin D3 helps your body absorb calcium. Without vitamin D3, your body cannot use the calcium and other minerals you ingest to maintain strong bones. Studies show insufficient vitamin D3 can cause pain in the back and leg bones, joints, and ribs. This may be due to gradual bone loss.

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Muscle Pain

Deficiency in vitamin D3 may cause muscle pain. One study of people with chronic muscle pain showed that 71 percent of them were deficient in this essential nutrient. Several other studies show that vitamin D3 supplements can decrease pain in those with deficiencies who are also dealing with chronic pain.

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People who are overweight or obese may have low levels of vitamin D3. Fat cells will often absorb vitamin D3 instead of letting the vitamin do its important work. Malabsorption of various nutrients, including vitamin D, is associated with obesity; if you are overweight, make sure that you have enough vitamin D3 to contribute to your body's health.

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Cognitive disorders

If you are constantly forgetting things, you may be dealing with a lack of vitamin D3. Low vitamin D3 is a risk factor for disorders such as dementia and cognitive impairment, especially in older adults. People who have dementia show a marked decrease in vitamin D3.

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Low levels of vitamin D3 can lead to depression. Doctors have discovered a close link between depression and inadequate levels of vitamin D3 in the bloodstream, especially in older adults. One study showed that 65 percent of subjects with depression also had low vitamin D3.

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Slow Healing

If you get injured and it takes a long while for you to heal, it might be because you have an inadequate amount of vitamin D3. The nutrient is crucial for rebuilding new skin, so having too little can result in wounds healing slowly, especially after surgery.

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Hair Loss

If you're losing your hair, one possible cause is a deficiency in vitamin D3. People with alopecia areata, an autoimmune disease that affects the hair, seem to be at increased risk of vitamin D deficiency. Vitamin D stimulates hair follicles to grow. New, healthy follicles help maintain thickness and prevent hair loss.

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Bone Loss

Studies point to a strong link between lack of vitamin D and mineral loss in bones; a lack of vitamin D3 can interfere with the absorption of calcium; this causes bone loss, because the body needs both calcium and vitamin D for this process. If you know you need more calcium, chances are you also need to increase your intake of vitamin D3. Older adults are at increased risk of bone fractures from falls because they are more likely to have vitamin D and calcium deficiencies.

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This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.