Vitamin D: Let the Sunshine In
What you need to know about vitamin D deficiency
Marie grabs a novel and heads to her back yard. “I’ll be on the deck, reading,” she calls to her husband. “Doctor’s orders.” After a battery of tests to understand why Marie was always tired, her doctor discovered a vitamin D deficiency. Along with some nutritional adjustments, he prescribed 15 minutes of sitting in the sunshine each day as part of her treatment.
Concerns about developing skin cancer impel many of us to slather our bodies with sunscreen or avoid the sun altogether, thus depriving ourselves of the benefits of vitamin D. Along with other dietary considerations (like milk allergies or a strict vegetarian meal plan), individuals may unintentionally contribute to vitamin D deficiency. “You get vitamin D either through your diet or from sun exposure,” says registered dietitian Lona Sandon. “People who live in areas with less sun, those who don’t get outside much and those with dark skin may not get adequate vitamin D from the sun.” Sandon says overweight people are also at a higher risk: “Anyone with a BMI greater than 30 may need more vitamin D, as it can become trapped in fatty tissue and not circulate throughout the body as well as it should.”
Risks of D deficiency
Because the “sunshine” vitamin helps the body use calcium from food, it is necessary for strong bones. For centuries, vitamin D deficiency was associated with rickets, a disease in which bone tissue doesn’t properly mineralize, leading to soft bones and skeletal deformities.
Increasingly, research has shown vitamin D to be important in protecting against a wider host of health problems, from cardiovascular disease and cancer to severe childhood asthma and age-related cognitive impairment. Furthermore, low levels of vitamin D may be linked to depression. “Our findings suggest that screening for vitamin D levels in depressed patients — and perhaps screening for depression in people with low vitamin D levels — might be useful,” said Dr. E. Sherwood Brown, senior author of a recent D-centric survey conducted by the University of Texas Southwestern Medical Center and the Cooper Center Longitudinal Study. “But we don’t have enough information yet to recommend going out and taking supplements.”
More research is also needed to determine if vitamin D could play a role in the prevention and treatment of other conditions, including type 1 and type 2 diabetes, hypertension, glucose intolerance and multiple sclerosis.
Getting your vitamin D
It’s commonly believed that your skin produces all the vitamin D your body needs with 15 minutes of daily sun exposure. “For those who are at high risk of skin cancer or are concerned about overexposure, dietary vitamin D offers a solution,” says clinical nutritionist Jo Ann Carson, PhD. “Foods rich in vitamin D include fatty fish like salmon and tuna, shiitake mushrooms, egg yolks and vitamin D-fortified dairy products.
A vitamin D supplement can also help, but “don’t take more than 1,000 IU per day,” advises Dr. Carson. “Be sure to take the form called cholecalciferol, or vitamin D3, because it results in the most active vitamin D in the body.”
Vitamin D & Babies
There is some controversy about the amount of vitamin D that children should take in. The American Academy of Pediatrics and the Institute of Medicine recommend a daily intake of 400 IU per day of vitamin D during the first year of life, beginning in the first few days, and 600 IU for everyone over age 1. To ensure optimal vitamin D levels, consult your child’s pediatrician.
Pennsylvania native Claire Yezbak Fadden enjoys soaking in the California sunshine for a few minutes every day.