Caffeine
A couple cups of coffee makes some people race to the bathroom, but it can have the opposite effect, too. The caffeine in coffee and soft drinks can keep your body from holding onto water, and you need H2O to stay regular. If you’re constipated, skip that second cup until things pass.
Alcohol
Like coffee, booze can make it hard for your body to hang onto water. That can spell trouble for your bathroom visits until you get hydrated again. If you’re going to have a cocktail, nurse a glass of water at the same time to keep things flowing.