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Dairy-Rich Snacks

Some people develop intolerances to the proteins in dairy (casein and whey) as they get older—and if you're noticing a lack of energy after eating yogurt or cheese, a dairy intolerance could be the culprit. "At least 50 to 60 percent of my patients complain of fatigue, and I would estimate that 20 to 30 percent of those people feel better off dairy," says Lyla Blake-Gumbs, MD, from the Center for Integrative Medicine at the Cleveland Clinic. (Blake-Gumbs says it may be because our bodies mistakenly develop an immunological reaction to the proteins, building an army of antibodies to mobilize against the proteins whenever they show up, resulting in fatigue.)