If you fall into one of the following groups, you may
need to supplement your Vitamin D intake daily:
- People with limited sun exposure. The amount of vitamin D formed from exposure to the sun is affected by season and latitude. Generally, in northern and north eastern states, there aren’t enough UVB rays to form vitamin D during the fall and winter months.People who are homebound and whose jobs are primarily indoors limit their sun exposure and are likely not obtaining significant amounts of vitamin D from sunlight.
- People who use sunscreen. The use of sunscreen prevents the formation of vitamin D. Even sunscreen with an SPF of 8, an amount found in many daily moisturizers, can greatly reduce vitamin D production. In one research study, nearly half of people who stated they always wore sunscreen while outdoors had a vitamin D deficiency.
- People with more skin pigment. People with dark colored skin synthesize less vitamin D on exposure to sunlight than those with light colored skin. The risk of vitamin D deficiency is particularly high in dark-skinned people who live far from the equator. One U.S. study reported that 42% of African American women between 15 and 49 years of age were vitamin D deficient compared to 4% of white women.
- Seniors. The elderly have reduced capacity to synthesize vitamin D in skin when exposed to UVB radiation, and the elderly are more likely to stay indoors or use sunscreen, which blocks vitamin D synthesis. Institutionalized adults who are not supplemented with vitamin D are at extremely high risk of vitamin D deficiency. In fact, vitamin D levels in elderly subjects have been found to be approximately 30% of the levels found in young adults.It’s estimated that more than 50% of adults over age 50 in the United States and Europe are at risk of vitamin D deficiency. One study found that in Boston at the end of the summer, 30% of whites, 42% of Hispanics, and 84% of African Americans had vitamin D deficiencies.
- Exclusively Breast-Fed Infants. Infants who are exclusively breast-fed and do not receive vitamin D supplementation are at high risk of vitamin D deficiency, particularly if they have dark skin and/or receive little sun exposure. The American Academy of Pediatrics recommends that all infants be given a vitamin D supplement of 400 IU/day.
- Those who are Overweight. Obesity increases the risk of vitamin D deficiency. Once vitamin D is synthesized in the skin or ingested, it is deposited in body fat stores, making it less bioavailable to people with large stores of body fat.