If you avoid the sun, have milk allergies, or follow a strict vegan diet, you may be deficient in vitamin D. Vitamin D, also known as the sunshine vitamin, is produced by the body in response to skin exposure to sunlight. It is also found naturally in a few foods, such as fish, fish liver oils, and egg yolks, as well as fortified dairy and grain products.
Vitamin D is necessary for strong bones because it aids the body’s utilization of calcium from the diet. Traditionally, vitamin D deficiency has been linked to rickets, a disease in which bone tissue fails to mineralize properly, resulting in soft bones and skeletal deformities. However, research is increasingly revealing the importance of vitamin D in preventing a variety of health problems.
Vitamin D Deficiency Symptoms and Health Risks
Vitamin D deficiency symptoms include bone pain and muscle weakness. However, the symptoms are subtle for many people. Even if no symptoms exist, a lack of vitamin D can be harmful to one’s health. Low vitamin D levels in the blood have been linked to the following:
• a higher risk of dying from cardiovascular disease
• Cognitive decline in the elderly
• Children with severe asthma
Vitamin D may play a role in the prevention and treatment of a variety of conditions, including type 1 and type 2 diabetes, hypertension, glucose intolerance, and multiple sclerosis, according to research.
Vitamin D Deficiency Causes
Vitamin D deficiency can occur for a variety of reasons, including:
Over time, you do not consume the recommended levels of the vitamin. This is likely if you adhere to a strict vegan diet, as the majority of natural sources are animal-based, such as fish and fish oils, egg yolks, fortified milk, and beef liver.
Your time in the sun is limited.
Because vitamin D is produced by the body when your skin is exposed to sunlight, you may be at risk of deficiency if you are housebound, live in northern latitudes, wear long robes or head coverings for religious reasons, or have a job that prevents you from getting enough sun. Because there is less sunlight available during the winter, vitamin D deficiency may be more prevalent.
You have a dark complexion. Melanin, a pigment, reduces the skin’s ability to produce vitamin D in response to sunlight exposure. According to some studies, older adults with darker skin are at a higher risk of vitamin D deficiency.
Vitamin D cannot be converted to its active form by your kidneys. People’s kidneys become less capable of converting vitamin D to its active form as they age, increasing their risk of vitamin D deficiency. Vitamin D cannot be properly absorbed by your digestive tract. Certain medical conditions, such as Crohn’s disease, cystic fibrosis, and celiac disease, can impair your intestine’s ability to absorb vitamin D from food.
You are overweight. Fat cells extract vitamin D from the blood, altering its release into the circulation. People with a BMI of 30 or higher frequently have low vitamin D levels in their blood.
Vitamin D Deficiency Tests
The 25-hydroxy vitamin D blood test is the most accurate way to determine how much vitamin D is in your body. For healthy people, a level of 20 nanograms/milliliter to 50 ng/mL is considered adequate. Vitamin D deficiency is indicated by a level less than 12 ng/mL.
Vitamin D Deficiency and Its Treatment
Vitamin D deficiency is treated by increasing vitamin D intake (through diet and supplements). Vitamin D levels below 20 ng/mL are generally considered inadequate and require treatment, but there is no consensus on what constitutes optimal vitamin D levels, and this is likely to vary depending on age and health conditions.
To maximize bone health, the Institute of Medicine upped the RDA for vitamin D to 600 IU for everyone younger than 70 and to 800 IU for adults older than 70. Previously, 2,000 IU was considered the maximum safe level, but that was increased to 4,000 IU. Depending on the severity of the deficiency, doctors may recommend higher doses of vitamin D than the recommended 4,000 IU per day.
If you have risk factors for vitamin D deficiency, such as not spending enough time in the sun or always being careful to cover your skin (sunscreen inhibits vitamin D production), you may want to talk to your doctor about taking a vitamin D supplement