Surprising Reasons You’re Feeling Blue

One in five of us has a chemical intolerance (and probably doesn't know it) to some of the 80,000 odorless chemicals in perfume, sunscreen, detergent and (it seems) just about everything else that's on and in and around us, found a study at the University of Texas at San Antonio. The symptoms may be as subtle as feeling sad, sluggish or irritable. Avoid (obvious) triggers like fragrances and pesticides—and tricky, often-overlooked ones like vinyl shower curtains, highlighters, printers,and others on this list.

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