Q. In the summer, my 5-year-old plays nonstop. How can I tell if he's getting dehydrated?
A. When kids are active, the heat makes them sweat, of course, and this can set them up for dehydration. Since children have more skin surface relative to their body weight, they can lose more fluid through the skin in hot weather and become dehydrated more quickly.
Signs of dehydration include dry, pale skin; infrequent urination; dark-yellow urine; fatigue; irritability; and a racing heart. Thirst is a symptom as well -- though be sure your child understands that feeling thirsty shouldn't be his first signal that it's time to take a drink. By then, the body's already in the early stages of dehydration.
If your child will be running around a lot, have him drink a couple of glasses of water an hour or so before he goes outside. As a general guide, kids need an ounce of fluid per pound per day. (So a 42-pound child, for instance, should drink about five 8-ounce glasses a day.) Keep a pitcher of water on the kitchen table or the porch, and put water bottles around his play area or have him keep one handy in his own fanny pack or bag. Ideally, he should take a drink break every 20 minutes.
If your child isn't crazy about plain water, add a twist of lemon or lime or flavor it with a few ounces of 100 percent fruit juice. (Sports drinks aren't necessary). Avoid caffeinated drinks, which can increase urination and, as a result, put him at a greater risk of dehydration. In hot weather, my wife, Martha, and I would start our children's morning off with a large fruit smoothie; we'd also stock trays of frozen pops in the freezer for them to suck on throughout the day.