Trends in calcium supplementation, National Health and Nutrition Examination Survey (NHANES) 1999-2014.
BACKGROUND
Long-term outcomes of supplemental calcium are inadequately understood. Recent research suggests that calcium from supplements may not be entirely free from unintended health consequences. Consequently, it is important to understand patterns and trends in use of calcium supplements.


OBJECTIVE
To report trends in supplemental calcium intake between 1999 and 2014, using NHANES data, overall and stratified by sex, race/ethnicity and age.


METHODS
A total of 42,038 adult NHANES participants were included in this analysis. For each survey period, we calculated the prevalence of calcium supplement use exceeding the Estimated Average Requirement (EAR) and Tolerable Upper Intake Levels (UL), and mean daily supplemental calcium dose among calcium-containing supplement users. Sample weights were applied. Linear regression was used to examine trends.


RESULTS
Overall, the prevalence of calcium supplement use at a dose ≥EAR increased between 1999 and 2000 and 2013-2014, from 2.5% (95% CI: 1.9-3.3%) to 4.6% (3.8-5.5%). Use ≥EAR peaked in 2003-2004 at 6.7% (5.3-8.5%) (p-quadratic trend<0.001). Mean supplemental calcium intake peaked in 2007-2008, thereafter decreasing (p-quadratic trend<0.001). The overall prevalence of intake ≥UL from supplemental calcium in 2013-2014 was 0.4% (0.2-0.8%). Use of supplemental calcium ≥UL peaked during 2007-2008 at 1.2% (0.7-2.0%). In all time periods, supplemental calcium intake tended to be greater among women, non-Hispanic whites and adults >60years.


CONCLUSIONS
We described the prevalence of U.S. adults consuming supplemental calcium ≥UL and ≥ EAR. While few were consuming supplemental calcium ≥UL, consumption ≥EAR was not uncommon, especially among women, non-Hispanic whites and older adults.
['Rooney|Mary R|MR|', 'Michos|Erin D|ED|', 'Hootman|Katie C|KC|', 'Harnack|Lisa|L|', 'Lutsey|Pamela L|PL|']
D000328:Adult D000368:Aged D000369:Aged, 80 and over D002136:Calcium, Dietary D019587:Dietary Supplements D005260:Female D006630:Hispanic or Latino D006801:Humans D008297:Male D008875:Middle Aged D009749:Nutrition Surveys D014481:United States D044465:Whites D055815:Young Adult
Trends Calcium Dietary supplements