Summertime Blues
Seasonal affective disorder (SAD) is a type of depression that usually crops up in the dark days of winter, when fewer hours of daylight can throw your body chemistry out of whack. But an unlucky few experience a hot-weather version of SAD, in which summer's abundant sunlight is responsible for symptoms like anxiety, irritability, insomnia and a lower appetite that leads to weight loss, says Raymond Crowel of the National Mental Health Association.

If this sounds like you, use blackout blinds to limit light in your home. Since people with SAD tend to feel uncomfortably warm at night, keep the temperature of your home low and take a cool shower before going to sleep (or snuggle up with a chilled hot-water bottle in bed).

Tossing and Turning
The lazy days of summer don't necessarily translate into peaceful, dreamy nights. For many people, summer is a time for troubled sleep — usually because the bedroom is too hot. Count on machinery to come to your rescue. If you need to turn on the air conditioner or a fan, do so. And crank up the dehumidifier, too, since humidity is another sleep stealer.

For some night owls, extended daylight disrupts their internal clock and robs them of their eight hours. Counter that effect by avoiding sunlight at the end of the day, from 6 p.m. onward, says Tracy Kuo, Ph.D., of the Stanford University Sleep Disorders Clinic. Alternatively, some morning people wake up much too early in the summer because of earlier sunrises. "Invest in an eye mask to shield out the light and enable you to sleep into the morning better," suggests Kuo.

Think Before You Plunge
It's tempting to blame an upset stomach, diarrhea or vomiting on an undercooked burger, but that before-lunch dip in the pool may be the real culprit. When a swimming pool isn't decontaminated thoroughly, it may harbor troublemaking germs. Luckily, preventing an infection is relatively simple, says Michael J. Beach, Ph.D., of the Centers for Disease Control and Prevention.

For starters, don't swallow pool water, don't swim with an open cut and always shower after you climb out of the water. And don't let a "clean" odor fool you: A chlorine smell actually indicates that there is not enough of the germ-cleaning chemical in the pool, so put off getting your toes wet until another time.

Sights for Sore Eyes
The fireworks that delight kids (and adults!) every July are great fun — from a distance. Up close and personal, they can cause serious eye injuries. How to stay safe? Catch them on TV, suggests Kenneth B. Simons, M.D., a professor of ophthalmology at the Medical College of Wisconsin in Milwaukee. Or watch a town fireworks display from a distant vantage point. Equally important: Make sure your kids and their friends don't set off any fireworks on their own — even sparklers can cause serious trouble.

If someone does injure an eye, don't touch the area — go to an emergency room immediately. For protection en route, place an eye shield from a first-aid kit over the eye, or craft a makeshift guard from a piece of cardboard or a paper cup that has been cut shorter.

The Cold Truth
Hard to believe, but people can suffer from the cold during the summer. Hypothermia — when the body's temperature dips dangerously low — kills Americans every month of the year, in all 50 states, according to Eduardo Azziz-Baumgartner, M.D., of the Centers for Disease Control and Prevention. People can get into trouble when they're swimming in chilly water, or hiking or camping at high altitudes or in the desert.

Be on the lookout for signs of hypothermia: shivering, chattering teeth, cold (or blue or pale) skin, mental confusion and poor hand coordination. If you suspect someone has become seriously cold, seek medical help immediately. While you're waiting, remove any wet clothing from the victim and warm her up with blankets or by rubbing her skin (chest, neck and head areas first). If she's conscious, give her a warm, nonalcoholic beverage to drink.

The Deal With Heels
Those strappy shoes you love so much can have a downside. They create friction that, combined with the usual dryness of the skin on the bottom of your feet, can cause cracked heels. In extreme cases, your feet can bleed or become infected, says Helena Anne Reid, a podiatrist in Moline, Ill.

Solution? "Use a pumice stone on your heels every day in the bath or shower, then find a cream you like and put it on your feet twice a day," says Dr. Reid. She adds, "If an over-the-counter cream doesn't help heal cracks, talk to your doctor about a prescription product." Protect your feet further by alternating between wearing sandals and closed shoes. And don't walk barefoot outdoors.