Roughly half of all Americans — older adults in particular — don’t get enough vitamin D. What are the implications of this? This nutrient is essential to our muscles, bones and immune systems. New research links low levels of vitamin D to a growing list of health problems, including heart disease
Low Vitamin D Can Mean Trouble
Vitamin D helps form and strengthen bones by allowing the body to absorb calcium. Without adequate vitamin D, bones become thin and brittle. The vitamin also helps our muscles and immune system function.
A deficiency in vitamin D is a concern because the nutrient appears to play a role in several serious medical conditions, including:
- Cancer — Research suggests that vitamin D may help protect against breast, prostate and colon cancer
- Diabetes — Vitamin D may reduce the risk for type I diabetes in children
- Heart disease — Low blood levels of vitamin D may be related to cardiovascular disease and high blood pressure
- Osteoporosis — Low levels of vitamin D have been tied to osteoporosis and hip fractures in older women
With all of these findings, researchers point out that further investigation is needed, but it is projected that the incidence of many of these diseases could be reduced by 20 to 50 percent or more, if the occurrence of vitamin deficiency and insufficiency were eradicated by increasing vitamin D intakes.
“Certain factors may limit some individuals’ ability to obtain vitamin D through sunshine absorption, including seasonal conditions and use of sunblock,” said Gay Bonilla, RD, CNSD, an advanced practitioner and dietitian at Sharp Grossmont Hospital. “Individuals with lighter skin are able to absorb vitamin D more easily and quickly through sun exposure compared to darker-skinned individuals. In addition, vitamin D from food or supplements may be difficult to absorb due to malabsorptive conditions, such as Crohn's, celiac disease or gastric bypass.”
What Causes Low Levels of Vitamin D?
Experts suspect there are two reasons why people have trouble getting enough vitamin D. One is that few foods contain the vitamin naturally. Another is that a common source of vitamin D is ultraviolet radiation from the sun, which penetrates uncovered skin and converts chemicals in the body into the vitamin. While traditionally many of us got our vitamin D from sunlight, the risk for skin cancer has led many people to limit their time outdoors or to wear sunscreen, which often blocks vitamin D-producing rays.
Ensuring You Get Enough
The government currently recommends that healthy people get the following amounts of vitamin D each day:
- Children and adults ages 50 and younger: 200 international units (IU)
- Adults ages 51 to 70: 400 IU
- Adults ages 71 and older: 600 IU
It is important to note that, according to the University of California Scientists Panel, new evidence indicates that, in order to prevent or substantially reduce the incidence of breast and other cancers, type I diabetes and multiple sclerosis, there is need for new public health policy to raise the intake of vitamin D closer to 1,000 to 2,000 IU per day for adults and teenagers, and 1,000 IU for children ages 1 to 12. This is the current upper limit of the National Academy of Sciences, Institute of Medicine, Food and Nutrition Board.
Follow these tips to ensure you are getting your daily requirement of vitamin D:
- Eat foods that contain a natural source of vitamin D, such as eggs, mackerel, wild salmon, farmed salmon, canned tuna or dairy and soy products fortified with vitamin D
- Have your blood level of vitamin D checked by your doctor if you're worried that you aren't getting enough
- Take a vitamin D3 supplement to meet the daily goal if your dietary vitamin D and sun exposure is limited
- While sunblock is vital for protection against skin cancer, sunburn and sun damage, allow about 10 minutes of sunshine for those with light skin, or 20 minutes for those with dark skin
- Find healthy recipes to help boost your vitamin D intake.
For More Information
To learn more about Sharp's nutrition services or to find a Sharp-affiliated physician, search for San Diego doctors or call 1-800-82-SHARP (1-800-827-4277), Monday through Friday, 8 am to 6 pm.