You may be at risk of vitamin D deficiency if you avoid the sun, have milk allergies, or follow a strict vegan diet. Vitamin D, also known as the sunshine vitamin, is produced by the body in response to skin exposure to sunlight. It is also naturally occurring in a few foods, including certain types of fish, fish liver oils, and egg yolks, as well as fortified dairy and grain products.
Vitamin D is necessary for healthy bones because it aids the body in utilizing calcium from the diet. Vitamin D deficiency has historically been associated with rickets, a disease in which bone tissue does not mineralize properly, resulting in soft bones and skeletal deformities. However, research is increasingly demonstrating the critical role of vitamin D in preventing a variety of health problems.
Vitamin D Deficiency Symptoms and Health Risks
Symptoms of bone pain and muscle weakness may indicate that you are deficient in vitamin D. However, many people experience only subtle symptoms. Nonetheless, even in the absence of symptoms, insufficient vitamin D can pose health risks. Vitamin D deficiency has been linked to the following:
- Risk of death from cardiovascular disease is increased
- Age-related cognitive decline in older adults
- Children with severe asthma
Vitamin D may play a role in the prevention and treatment of a variety of different conditions, including type 1 and type 2 diabetes, hypertension, glucose intolerance, and multiple sclerosis, according to Cancer Research.
Vitamin D Deficiency Causes
Vitamin D deficiency can occur for a variety of reasons, including the following:
Over time, you do not consume the recommended amount of vitamin. This is likely if you follow a strict vegan diet, as the majority of natural sources include fish and fish oils, egg yolks, fortified milk, and beef liver.
Your time in the sun is limited. Because vitamin D is produced 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 being exposed to sunlight. Vitamin D deficiency can be more prevalent during the winter months due to the reduced amount of sunlight available.
You have a dark complexion. Melanin inhibits the skin’s ability to produce vitamin D in response to sun exposure. According to some studies, older adults with darker skin are at an increased risk of vitamin D deficiency.
Vitamin D cannot be converted to its active form by the 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 absorption is inadequate in the digestive tract. Certain medical conditions, such as Crohn’s disease, cystic fibrosis, and celiac disease, can impair the 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. Individuals with a body mass index of 30 or greater frequently have low vitamin D levels in their blood.
Vitamin D Deficiency Tests
The 25-hydroxy vitamin D blood test is the most accurate method for determining the amount of vitamin D in your body. For healthy individuals, a level of 20 nanograms/milliliter to 50 ng/mL is considered adequate. Vitamin D deficiency is defined as a level less than 12 ng/mL.
Vitamin D Deficiency Treatment
Vitamin D deficiency is treated by increasing vitamin D levels through diet and supplementation. Although there is no consensus on the optimal vitamin D level for health – which is likely to vary according to age and health status – a concentration of less than 20 nanograms per milliliter is generally considered insufficient and requires treatment.
To optimize bone health, the Institute of Medicine increased the recommended dietary allowance (RDA) of vitamin D to 600 international units (IU) for all adults ages 1 to 70 and to 800 IU for adults over age 70. Additionally, the safe upper limit was increased to 4,000 IU. Doctors may prescribe up to 4,000 international units (IU) to treat vitamin D deficiency.
If you spend little time in the sun or are constantly covering your skin (sunscreen inhibits vitamin D production), you should consult your doctor about vitamin D supplementation, especially if you have risk factors for vitamin D deficiency.