Over the past decade, a flurry of reports linking low levels of vitamin D to cancer, heart disease, diabetes and other diseases has led many doctors to routinely test vitamin D levels of their healthy patients. what But there's no good reason to not, based on a recent suggestion from the US Preventive Services Task Force (USPSTF) published this week. History of Internal Medicine.
After reviewing the outcomes of 25 vitamin D studies, the panel concluded that knowing their vitamin D levels isn't helpful for most individuals. For one thing, experts don't agree on what vitamin D deficiency means. Some laboratories define it below 20 nanograms per milliliter (ng/mL), others below 50 ng/mL. Also, vitamin D tests will not be standardized or reliable.
Perhaps most significantly, even when you could have “low” vitamin D levels, there may be little evidence that taking a vitamin D complement will do you any good—with one exception. People with vitamin D deficiency who take supplements are less prone to fall. It is sensible that vitamin D plays a key role in keeping bones and muscles strong.
Our bodies make vitamin D when sunlight hits our skin (hence the nickname, the “sunshine vitamin”). Fatty fish (akin to salmon and mackerel), eggs, and mushrooms contain small amounts of vitamin D. It is added to exploit in addition to some yogurts, juices and breakfast cereals.
Recommended Vitamin D Intake
400 IU/day for youngsters
600 IU/day for youngsters 1 to 13 years of age
600 IU for everyone aged 14 to 70 years
800 IU for those 71 years and older
The really helpful each day intake ranges from 400 international units (IU) to 800, depending on age (see “Recommended Vitamin D Intakes”). However, many individuals – including healthcare professionals – take high doses of vitamin D in complement form to forestall chronic disease, despite clear evidence of advantages.
Dr. Manson explains that low vitamin D levels may be only one sign of poor health. “If you're in poor health, you're not going outside for a walk, bike ride, or other exercise,” she says. Being indoors more means you don't get enough sunlight to make vitamin D. Also, people who find themselves obese have lower vitamin D levels. Both obesity and lack of exercise contribute to higher rates of cancer and heart disease, so these aspects may explain the diseases quite than low vitamin D levels.
We could have a clearer picture of vitamin D's role in our health in just a few years. A nationwide trial involving about 26,000 people led by Dr. Manson is underway, with results expected in late 2017. The Vitamin D and Omega-3 Trial (VITAL) goals to find out whether taking 2,000 international units (IU) of vitamin D or fish. Oil pills reduce the chance of cancer, heart disease and stroke in individuals who don't currently have these diseases.
In the meantime, there isn't a practical reason for most individuals to get a vitamin D test. But there are exceptions, says Dr. Manson. People who might have testing include those that:
- Have osteoporosis or other bone health problems.
- There are conditions that affect fat absorption, including celiac disease or weight reduction surgery
- Routinely take medications that interfere with vitamin D activity, including anticonvulsants and glucocorticoids
The Institute of Medicine, which officially sets dietary reference points based on a radical review of all available evidence, concluded that a vitamin D blood level of 20 ng/mL is vital to keep up healthy bones. Coffee provides vitamin D.
Dr. Manson says there's no additional benefit to going any higher, although a goal of 30 ng/mL is cheap. But some laboratories are recommending ranges that exceed 50 ng/mL, which is potentially dangerous, Dr. Manson cautioned. Too much vitamin D could cause calcium to accumulate in your blood, which may damage your heart, blood vessels, and kidneys.
How are you able to be certain that you're getting enough vitamin D? When possible, aim to get the really helpful each day intake on your age from moderate sun exposure. and an appendix if required. How much sun is enough is determined by where you reside and the weather. In the United States, for those who live north of the road that stretches from San Francisco to Richmond, Virginia, it's difficult to make more vitamin D from sunlight in the autumn, winter, and spring.See map below).
If you don't get enough vitamin D from the sun or food, a complement is sensible. Taking 1,000 or 2,000 international units (IU) of vitamin D a day is comparatively secure. The secure upper limit is 4,000 IU a day, but consider that there may be very limited research on the long-term safety of taking this amount. “More is not necessarily better when it comes to vitamins,” says Dr. Manson.
Latitude and vitamin D production within the skin
Except in the summertime months, if there may be any vitamin D obtained from the sun at latitudes above 37 degrees north of the sun (within the United States, the shaded area on the map) or below 37 degrees south of the equator, the body gets an excessive amount of vitamin D. Makes less.