Vitamin D Lowers Tooth Decay Risk in Kids
February 27, 2013

By Nancy Volkers
InteliHealth News Service

INTELIHEALTH - Vitamin D reduces the risk of tooth decay in children, says a review of published research.

The review included mostly studies from the 1920s, 1930s and 1940s. Since then, little research has been done on vitamin D and tooth decay. The U.S. National Research Council stated in 1989 that any link between vitamin D and tooth decay connection was "unresolved."

A researcher from the University of Washington reviewed 24 studies. They found that children who got vitamin D supplements (18 studies) or UV light treatments (6 studies) were about half as likely to get tooth decay during the next year or so as children who did not.

The studies included 2,827 children. Their ages ranged from 2 to 16. The researcher doing the review found some sources of bias:

• In 19 of the studies, the researcher knew which children were getting supplements and which were not.
• In 14 of the studies, there was no control group. For example, children were given vitamin D pills or nothing, rather than vitamin D pills or placebo pills.
• In 5 studies, children were assigned to receive vitamin D or UV light based on a history of tooth decay. In a standard clinical trial today, children are randomly assigned to treatments.
• In 13 studies, partial funding was provided by commercial companies that could have benefited from the results.

The author concludes with "low certainty" that vitamin D supplements reduce the risk of tooth decay. He noted that the better-designed trials showed a benefit to vitamin D. These trials randomly assigned children to vitamin D or placebo. The researchers did not choose which children received vitamin D.

All of the vitamin D trials were conducted in the 1920s through 1940s. Four of the six UV light studies were conducted in the 1930s. The other two were done in 1975 and 1989.

A drawback to this review is that it focuses on children who grew up in the 1920s, '30s and '40s, the author notes. These children had different lifestyles and diets than children do today. They likely spent more time in the sun, ate more animal fats and consumed less fluoride. The author suggests that clinical trials be started to look at the effect of vitamin D supplements on tooth decay risk and gum disease risk.

The study appears in the February issue of the journal Nutrition Reviews.