Many Americans consume suboptimal levels of calcium and vitamin D, despite the fact that these are vital nutrients relating to bone health during all stages of life. Researchers set out to find American subpopulations that were most in need of the two nutrients in order to identify target groups for vitamin supplements and outreach programs.

The researchers findings are available in the Journal of the American College of Nutrition.

The study used data from the National Health and Nutrition Examination Survey from 2001 through 2008. The sample population totaled 227,528, all of whom gave dietary intake data and personal information regarding gender, age, race, weight, household income level, dietary supplement use and vegetarian status.

"The National Cancer Institute method was used to estimate usual calcium and vitamin D intakes by source; these figures were compared to the established Dietary Reference Intakes for US residents over the age of three," according to a press release describing the results.

Researchers found that 4- to 8-year-old children were more likely to obtain the daily-recommended dairy intakes than older children and adults of all ages. Consumption of food rich in calcium and vitamin D was found to decrease with age in adults.

As would be expected, adults taking vitamin supplements showed lower prevalence of insufficiency, while vegetarian status was not linked to calcium or vitamin D deficiencies.

"Over-nutrification," or excessive intake of these nutrients in excess of the upper intake level, were not widely present in the analysis.

"Our results showed for the first time that low-income, overweight, and/or obese minority populations may be at a greater risk of calcium and vitamin D insufficiency," said Dr. Taylor C. Wallace. "The results show that large portions of the US population do not obtain adequate calcium and vitamin D intakes from food alone."

The results are vital to identifying those populations most in need of a focused public health awareness campaign and health related messaging in regards to optimal bone health.