With the increased humidity and heat, it’s important to stay hydrated. According to the Mayo Clinic, if you’re exercising or even just doing everyday activities in humidity, your sweat can’t evaporate to cool down your body temperature. Children, older people, and endurance athletes are more prone to dehydration.

How much water do you need per day? Forget the traditional advice to drink eight 8 oz. glasses per day. The amount of water your body needs depends on many variables, including body weight, activity, and where you live. Aim for .5 to 1 oz. per pound of body weight, with the higher amount if you’re in a hot climate or exercising.

Nutritionists suggest sipping throughout the day rather than drinking large amounts at once. When we consume large amounts of water, our kidneys are signaled to excrete water, blocking the antidiuretic hormone vasopressin, which retains water in the body. In rare cases, drinking an extreme amount of water in a short time can cause hyponatremia, a sometimes fatal condition in which the level of sodium in blood drops too low.

Dehydration puts us at risk for heat exhaustion or heat stroke, cramps, seizures, or even kidney failure as well as an increased risk for kidney stones, caused by increased calcium in urine. Symptoms of dehydration include low blood pressure, rapid heart rate, excessive thirst, and fever.

What can you do to avoid dehydration? Be sure to sip water throughout the day. If you’re exercising over sixty minutes or vigorously for less time, choose a sports drink that contains 13-19 g carbohydrates and 80-110 mg sodium. Avoid alcohol and caffeine, both of which are dehydrating. For each cup of coffee, iced tea, or cocktail, drink a glass of water.