How to Increase Your Willpower

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Making the right choices about whether to go to the gym or happy hour often comes down to one thing: willpower. So it's good to have willpower, but it's not like you can flip a switch and have more when you need it. In fact, some surprising physiological and psychological factors cause willpower to rise and fall. Remember these unexpected resistance boosters the next time you're faced with temptation.

1. Willpower decreases when you get fewer than seven hours of sleep.

Not only does a lack of rest make you grouchy, but it also causes the hormones that regulate your appetite to go wonky. “When you're tired, your body's levels of ghrelin (a hunger-stimulating hormone) and leptin (a metabolism-regulating hormone) can become off-balance," says Erin Palinski, RD, CDE, LDN, CPT, author of the forthcoming Belly Fat Diet for Dummies. "That increases your appetite, causing you to eat more and crave greasy and sugary foods." So get a full night's worth of shut-eye to avoid overeating and choosing unhealthy nibbles the next day.

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