(NaturalNews) Millions of Americans are unable to meet recommended daily intakes of calcium and vitamin D because of socioeconomic conditions, even though they are vital nutrients in bone health during all phases of life, new research indicates.
"Calcium is the fifth most abundant element in the human body, contributing significantly to bone mineral density and micro-architecture. Skeletal calcium serves as a reservoir to maintain serum calcium levels. When calcium intake is insufficient to maintain serum concentrations from either dietary and/or supplemental sources, compensatory loss from the bone follows, weakening the skeleton and increasing risk of subsequent fracture," says an introduction to the study, which has been published by the peer-reviewed Journal of the American College of Nutrition, the official publication of the institution by the same name.
In their study, researchers set out to determine what the calcium and vitamin D intakes were among various specific subpopulations of Americans, in an attempt to identify those most in need of fortification/enrichment and supplementation.
'Low-income, overweight, minority populations'
Researchers used data from the 2001-2008 National Health and Nutrition Examination Survey, or NHANES. The combined sample totaled 227,528 participants who gave personal dietary intake data and other information regarding age, race, weight, gender, household income level, dietary supplement use and vegetarian status.
Scientists used the National Cancer Institute method to estimate usual calcium and vitamin D intakes by source. These figures were then compared to established Dietary Reference Intakes for U.S. residents over age three.
"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, a study co-author. "The results show that large portions of the U.S. population do not obtain adequate calcium and vitamin D intakes from food alone."
According to findings, children aged 4-8 years old were more likely to get recommended dairy intakes compared to older children of all ages. Food intakes of both nutrients decreased with age in adults.
Also, adults who used supplemental calcium and vitamin D showed a lower prevalence of insufficient levels, and intakes of both nutrients from food and dietary supplements were not related to vegetarian status, researchers said.
Excessive intakes of calcium and vitamin D that were above the tolerable upper intake level (UL) were low among the demographics examined, the study said; "over-nutrification" was not widely found across the analyses.
"Vitamin D aids in the absorption of calcium and its active role in bone health has been previously described," said the study. "Vitamin D is vital to the cell-mediated bone remodeling process. In humans, vitamin D is unique because it can be ingested as cholecalciferol (vitamin D3) or ergocalciferol (vitamin D2) and because the body can also synthesize it (from cholesterol) when sun exposure is adequate."
Definite socioeconomic implications
Researchers said the study's findings were important because they could be used to help focus public health and awareness campaigns, as well as messaging related to the significance of both nutrients in maintaining optimal bone health.
"Age- and gender-specific supplementation and modest use of fortification with calcium and vitamin D may be warranted for targeting certain subpopulations, particularly older adults, teenagers, minorities, and those who are low income and overweight and/or obese," the study says.
"This study aimed to characterize usual intakes of calcium and vitamin D from food and dietary supplements in specific subpopulations of Americans so that fortification/enrichment and supplementation efforts may be better targeted. Low-income, overweight, and/or obese minority populations may be at a greater risk of calcium and vitamin D insufficiency," it concluded.