Contrary to some earlier findings, most Americans and Canadians are getting enough vitamin D and calcium, according to a new report from the Institute of Medicine.
The report updates the institute's recommendations for daily intakeof these two nutrients, and was written by an expert committee usinginformation from more than 1,000 published studies.
The committee concluded that people between the ages of 1 and 70 need no more than 600 international units (IU) ofvitamin Dper day, while those over 70 could need up to 800 IUs.
When it comes to calcium, people need between 700 milligrams and 1,300 milligrams per day depending on their age. {Related Infographic:See a complete table of the recommendations for people of all ages.}
Based on the committee's analysis, the number of people in NorthAmerica declared to have vitamin D deficiency has been overestimated.The error stems in part from the fact that there is no standard fordetermining whether someone is deficient. In fact, a person might betold they have deficient or sufficient levels depending on thelaboratory that conducts their blood test, the researchers said.
And while studies based on dietary intake show the majority of North Americansdon't get enough vitamin Dfrom the food they eat, other findings reveal that most people do havesufficient vitamin D in their blood. The missing piece of the puzzle isthe sun -sunlight triggers the production of vitamin Dfrom other compounds in the body. The report indicates that for many individuals, the sun is an important contributor to a person's overall vitamin D levels.
However, the report found that girls between the ages of 9 and 18were at risk of not getting enough calcium, and the elderly miss themark for both vitamin D and calcium recommendations. People in thesegroups may need to increase their vitamin D and calcium intake throughfoods, or possibly a supplement, the researchers said.
The recommendations are made mainly withbone healthin mind, the committee said. Although mounting studies have shown vitamin D has a host of healthbenefits, including protection against diabetes, heart disease andcancer, the committee said the evidence was inconsistent andinconclusive. More studies are needed to determine whether thesenutrients have any other health advantages.
How much is too much?
The committee also weighed in on the upper limits for vitamin D andcalcium intake. Getting too much calcium could put people at risk forkidney stones, and too much vitamin D could damage the heart and kidneysand may increase the risk of death, the researchers said.
As food producers increase the amount of these nutrients in theirproducts, and people more frequently turn to supplements, there is agreater likelihood that people will take in high doses of vitamin D andcalcium.
The researchers emphasized the upper limits are not something peopleshould strive to achieve. The vitamin D limit for people over age 8 is4,000 IUs. For calcium, those from 19 through 50 should limit theirintake to 2,500 milligrams daily, and those 51 and older should limittheir intake to 2,000 milligrams daily, the committee said.
New numbers
The new recommendations come in three forms - the Estimated AverageRequirement (EAR), which is the level at which 50 percent of thepopulation's nutrition requirements are met; the Recommended DietaryAllowance (RDA), which is the level that will cover 97.5 percent of thepopulation's nutrition needs, and the upper level intake.
The EAR is useful for evaluating the intake of large groups ofpeople, such as setting the standard for nutrition in school lunches.The RDA is more appropriate for individuals to consider, and might bewhat a doctor recommends to his or her patient.
There is not enough evidence available to make EAR or RDArecommendations for children younger than a year, said Dr. StevenAbrams, a professor of pediatrics at the Baylor College of Medicine, whowas a member of the committee. As a result, the committee provided onlya rough estimate of recommendations for this age group, known asAdequate Intakes. It is recommended infants younger than a year get 400IU per day of vitamin D and 200 to 260 milligrams per day of calcium,depending on their age, Abrams said.
The IOM advises breastfed babies should be given vitamin D supplements, asbreast milk does not contain adequate levels of vitamin D, Abrams told MyHealthNewsDaily. On the other hand, it does contain sufficient levels of calcium.
The study was sponsored by the U.S. Department of Health and HumanServices, U.S. Department of Agriculture, U.S. Department of Defense,and Health Canada.
Follow MyHealthNewsDaily staff writer Rachael Rettner on Twitter@Rachael_MHND.
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