NEW YORK (Reuters Health)—Zinc supplementation may exacerbate rheumatoid arthritis (RA), new laboratory data suggest. In monocytes from patients with RA, researchers found high concentrations of intracellular zinc, which regulates immune responses by affecting signaling pathways, according to a report in Science Signaling.1 They also found increased expression of Zip8, a zinc-specific importer, in peripheral and…