|Nielsen, Forrest - Frosty|
Submitted to: National Nutrient Databank Conference
Publication Type: Abstract Only
Publication Acceptance Date: 4/2/2010
Publication Date: 7/25/2010
Citation: Nielsen, F.H., Scheett, A.J., Johnson, L.K., Lukaski, H.C., Roughead, Z.K. 2010. The use of Self-Reported Food Intakes to Formulate Hypotheses for Expected and Unexpected Findings in Copper, Zinc, and Magnesium Supplementation Studies. Presented at the National Nutrient Databank Conference. Interpretive Summary:
Technical Abstract: Objective: Determine whether food diary data provide possible explanations for results from supplementation studies that show limited relationships to blood and/or bone indicators of status. Materials and Methods: One two-year study assessed the daily supplementation with 600 mg calcium or 600 mg calcium plus 2 mg copper and 12 mg zinc on bone loss in 164 postmenopausal women. Five-day food diaries were completed four times during the study. Another study assessed inflammatory status by measuring C-reactive protein (CRP) in 100 women and men, ages 51-85, with sleep disorders and supplemented with 300 mg magnesium or a placebo for eight weeks. A 3-day food diary was completed three times. Results: Bone loss indicated by decreased whole body bone mineral densities and T scores was significant in women supplemented with copper and zinc, but not with calcium alone. Food diary data suggested possible reasons for not finding the expected attenuation by copper and zinc. Adequate copper status (only four women consumed <EAR) probably prevented a response to copper. In women consuming <EAR for zinc, those given zinc and copper did not, but those given calcium only did, show significant bone loss.This was opposite to that in women consuming <237 mg magnesium/day (95 percentile of a suggested EAR). Magnesium deficiency may induce bone loss and magnesium balance has been shown to be decreased by zinc. An expected decrease in plasma CRP with magnesium supplementation was associated with dietary magnesium in the other experiment. Significance: Food diaries provide useful information in supplementation studies.