Vitamin D is essential for health, but it is one of the most common nutrient deficiencies in the world. Vitamin D is not only a nutrient found in some food, but the body also makes Vitamin D when skin is directly exposed to the sun.
Dr. Michael Favorito, MD, an endocrinologist at Wilmington Health who is board certified in internal medicine and endocrinology, said maintaining adequate amounts of Vitamin D in the body is important and encourages people to achieve that by leading a healthy lifestyle, which he said includes eating a varied diet low in processed foods, low in simple sugars, and high in vegetables, regularly exercising, and maintaining a lean body weight.
Here are some things you might not know about Vitamin D.
1. Vitamin D supports bone health and may contribute to heart health
Favorito said Vitamin D helps maintain bone health, prevents osteoporosis, and may also play a role in immune health and cardiovascular health.
Vitamin D helps the body absorb calcium from food and supplements. According to the Office of Dietary Supplements, since calcium is one of the main building blocks of bone, a lack of Vitamin D can lead to bone diseases. Vitamin D is also needed for bone remodeling and bone growth, and without sufficient amounts bones can become thin, brittle or abnormally shaped.
“Some studies done in the older population show Vitamin D deficiency has a high association with increased falls,” Favorito said. “Vitamin D deficiency can cause muscle weakness. If you have a chronic D deficiency your balance is going to likely be off because of the weakness you have in your core muscles. Therefore, a good Vitamin D level is going to help you with that core strength and that can improve balance.”
According to U.S. National Library of Medicine, Vitamin D also plays a role in the functions of one’s nerve, muscle, and immune systems.
2. Severe Vitamin D deficiency can cause weakened bones and muscle weakness
Most who have a Vitamin D deficiency don’t have symptoms. However, Favorito said symptoms can appear in people with severe Vitamin D deficiency and chronic Vitamin D deficiency.
“More severe and prolonged Vitamin D deficiency can lead to bone pain, muscle weakness, weakened bones, and fracture,” he said, adding that some may also experience malaise or fatigue. “Severe Vitamin D deficiency can also lead to hypocalcemia, which has its own set of symptoms, such as muscle weakness, muscle aches, muscle spasms even to the point of tetany, and can lead to numbness and tingling in the extremities.”
Hypocalcemia is a condition where calcium levels in the blood is low.
“Long-term deficiency can lead to poor bone mineralization and repair, which may quietly contribute to the development of osteoporosis,” Favorito said.
Favorito said some don’t realize they have a Vitamin D deficiency unless they have an evaluation after breaking a bone or have a bone density test and receive a diagnosis.
3. Diet, lack of sun exposure, and certain GI illnesses can cause Vitamin D deficiency
Favorito said some causes of Vitamin D deficiency include a lack of the vitamin in diet, poor absorption due to gastrointestinal diseases, poor synthesis in the liver or kidney, and lack of sufficient sun exposure due to having deeply pigmented skin, living an indoor lifestyle, being covered up when outside, or always wearing sunblock.
“Vitamin D is found in fatty fish, leafy green vegetables, and it’s sometimes fortified in dairy products, but if someone’s lactose intolerant, or if someone is avoiding sugars or doesn’t eat vegetables, their diet may not include enough foods with Vitamin D,” Favorito said.
The liver and kidney help convert Vitamin D to its active form in the body. If a chronic condition prevents these organs from converting Vitamin D, this can lead to a deficiency. Malabsorption, or not absorbing enough Vitamin D from food, can also cause a deficiency. Favorito said some gastrointestinal conditions that can cause this problem include inflammatory bowel diseases, such as ulcerative colitis or Crohn’s disease.
Favorito said several other conditions can increase a person’s risk for Vitamin D deficiency, including obesity and other metabolic conditions such as prediabetes and diabetes.
4. Fatty Fish and fortified foods are good sources of Vitamin D
“You can naturally build your Vitamin D levels through dietary sources, exercise, and sun exposure,” said Favorito. Some fish, which includes salmon, tuna and mackerel, are good sources.
Other Vitamin D-rich foods include egg yolks and beef liver. Vitamin D is often added to foods, like milk and breakfast cereal, orange juice, soy drinks, and some other dairy products such as yogurt.
Though sunlight is vital to Vitamin D synthesis in the body, too much sun exposure can cause skin cancer. Therefore, skin exposure to sun should be limited.
5. Supplements help increase levels in those who are Vitamin D deficient
While diet can help people maintain adequate levels of Vitamin D, for many who are deficient in the nutrient supplements help boost the levels to a healthy level.
According to Favorito, Vitamin D supplements come in two forms: D2, which is ergocalciferol and comes from plant sources, and D3, which is cholecalciferol and comes from animal sources.
“D3 is commonly found over the counter, but the type you might get prescribed by a physician is ergocalciferol that’s D2,” Favorito said.
While Favorito said the risk of getting too much Vitamin D and reaching a toxic level is small, it can happen if someone overuses Vitamin D supplements and can lead to serious problems. Consult your health provider about your Vitamin D needs and supplement dosage for you.