Have you ever walked a long way on a hot summer's day and noticed that your fingers felt different, perhaps a bit swollen? Ever flown on a plane and noticed your feet swell up? Or maybe some mornings, you simply cannot fit your wedding ring back on after your shower? Swelling, or edema, usually occurs in the extremities but can happen anywhere on (and even all over) the body.

You will notice edema as puffiness of the tissue beneath the skin. Your skin may also appear stretched, shiny, or dimpled when pressed. Edema happens when blood vessels leak fluid. The body senses this leak, and the kidneys attempt to accommodate by retaining more water and more sodium. As fluid accumulates, more fluid leaks from the blood vessels, and this fluid leaks into and swells the surrounding tissues.

The blood vessels may leak fluid for many reasons. Eating too much salt or taking certain kinds of medications can spring the leak. Injury to the skin, such as sunburn, can cause the swelling. So can an allergic reaction or hives. Women who are pregnant often experience edema because the growing fetus and placenta require so much extra fluid. Edema may coincide with a woman's period or with premenstrual syndrome (PMS). The swelling also seems to occur when standing, walking, or sitting for long periods of time, especially during warm weather or on long flights or car rides.

Set an appointment with your doctor if you experience symptoms of edema. In some cases, edema is an indication of a serious underlying condition, including congestive heart failure, kidney damage or kidney disease, cirrhosis of the liver, or blockage of the lymphatic system.

In other instances, edema signals a medical emergency. Any sudden onset of edema should be addressed promptly. If swelling in the legs, ankles, or feet is accompanied by pain, this may be a sign of a blood clot, or deep vein thrombosis (DVT).

If swelling is mild, you can take self-care steps to relieve the swelling:

  • To ease swelling in legs, feet, and ankles, keep your legs raised above your heart.
  • Limit your salt intake and drink plenty of water.
  • Wear support or compression stockings.
  • Talk to your doctor or pharmacist about taking diuretics (water pills), which can help your body get rid of excess fluid and salt.
  • Massage may help to move fluid away from the extremities.
  • Exercise to pump excess fluid back toward the heart.