A paper published in the Journal of Consumer Research compared the choices people made about health issues when they were tired versus not and found that feeling blah leads to decisions that boost our health and safety. For instance, participants were more likely to choose a free sunblock over a free moisturizer after an exhausting workout. And people with a family history of kidney disease were more interested in early detection when they were feeling depleted than when they felt healthy. Need to sign up for new health insurance? Maybe you should do it when you’re under the weather.

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