Study links increased dietary zinc intake to reduced risk of Crohn's
WASHINGTON — Dietary intake of zinc was linked to reduced risk of Crohn’s disease, according to data presented at Digestive Disease Week 2015.
“Higher intake of dietary zinc was associated with reduced risk of Crohn’s disease,” Ashwin N. Ananthakrishnan, MBBS, MPH, from Massachusetts General Hospital, said during his presentation. “Considerable mechanistic plausibility supports this association, including the effect of zinc on autophagy and microbial clearance, innate immune response and maintenance of the epithelial barrier integrity.”
Ashwin N. Ananthakrishnan
Using the Nurses Health Study I and II, Ananthakrishnan and colleagues analyzed nearly 200,000 patients by using a validated semi-quantitative food frequency questionnaire to calculate total zinc intake. They adjusted for covariates such as smoking, oral contraceptive use, hormone therapy, physical activity, dietary fiber, vitamin D and BMI.
In a total of 3,317,550 person-years of follow-up, the study showed 269 incident cases (8/100,000 person-years) of Crohn’s disease and 338 incident cases (10/100,000 person-years) of ulcerative colitis.
When separated by quintile of zinc intake, Ananthakrishnan showed that as zinc intake increased, the hazard ratios of incident Crohn’s disease improved. Quintile 1 (for reference) had a hazard ratio of 1.0. HRs for the subsequent quintiles were 0.92 (0.65-1.29); 0.6 (0.4-0.89), 0.57 (0.38-0.86) and 0.74 (0.5-1.1; P (trend) = 0.003). The same pattern was not seen in ulcerative colitis, therefore zinc intake was not linked to risk of ulcerative colitis.
When stratified by specific zinc intake, less than 8 mg/day, which is the recommended intake) represented a HR of 1.0. Increased intake from 8 mg/day to 16 mg/day resulted in a HR of 0.69 (0.44-1.08), while intake of more than 16 mg/day produced a HR of 0.52 (0.32-0.86).
“The effects were more striking for dietary zinc than for supplementary zinc,” he said. – by Katrina Altersitz
For more information:
Ananthakrishnan AN, et al. Abstract 5. Presented at: Digestive Disease Week; May 16-19, 2015; Washington, D.C.
Disclosure: Ananthakrishnan reports acting as a consultant and on the advisory committee or review panel for Cubist, as well as a consultant and on the advisory committee or review panel for AbbVie. Please see the DDW faculty disclosure index for all other researchers’ relevant financial disclosures.