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Constantly caffeinating

Do it right
While caffeine can briefly suppress your appetite and acts as a diuretic, it has not been shown to cause real, sustainable weight loss.

Caffeine is thermogenic, which means it triggers the body to burn some calories through heat production. However, this doesn't seem to be enough to cause weight loss.

It's safe to boost your energy with a bit of caffeine before a workout, but too much caffeine can be harmful. "It's a central nervous system stimulant, which can affect your heart rate and blood pressure," says Dubost. (Keep your daily caffeine to 250 milligrams or less.)

Next: Gunning for grapefruit