Want to make a simple, ten-second check on the state of your health? Sneak a peek at your feet.
"You can detect everything from diabetes to nutritional deficiencies just by examining the feet," says Jane Andersen, DPM, president of the American Association of Women Podiatrists and a spokeswoman for the American Podiatric Medical Association.
The lowly left and right provide plenty of insightful data: Together they contain a quarter of the body's bones, and each foot also has 33 joints; 100 tendons, muscles, and ligaments; and countless nerves and blood vessels that link all the way to the heart, spine, and brain.
Unresolved foot problems can have unexpected consequences. Untreated pain often leads a person to move less and gain weight, for example, or to shift balance in unnatural ways, increasing the chance of falling and breaking a bone.
So when the feet send one of these 18 warning messages, they mean business.
1. Red flag: Toenails with slightly sunken, spoon-shaped indentations
What it means: Anemia (iron deficiency) often shows up as an unnatural, concave or spoonlike shape to the toes' nail beds, especially in moderate-to-severe cases. It's caused by not having enough hemoglobin, an iron-rich protein in the blood cells that transports oxygen. Internal bleeding (such as an ulcer) or heavy menstrual periods can trigger anemia.
More clues: On fingers as well as toes, the skin and nail beds both appear pale. The nails may also be brittle, and feet may feel cold. Fatigue is the number-one sign of anemia, as are shortness of breath, dizziness when standing, and headache.
What to do: A complete blood count is usually used to diagnose anemia. A physical exam may pinpoint a cause. First-step treatments include iron supplements and dietary changes to add iron and vitamin C (which speeds iron absorption).
2. Red flag: Hairless feet or toes
What it means: Poor circulation, usually caused by vascular disease, can make hair disappear from the feet. When the heart loses the ability to pump enough blood to the extremities because of arteriosclerosis (commonly known as hardening of the arteries), the body has to prioritize its use. Hairy toes are, well, low on the totem pole.
More clues: The reduced blood supply also makes it hard to feel a pulse in the feet. (Check the top of the foot or the inside of the ankle.) When you stand, your feet may be bright red or dusky; when elevated, they immediately pale. The skin is shiny. People with poor circulation tend to already know they have a cardiovascular condition (such as heart disease or a carotid artery) yet may not realize they have circulation trouble.
What to do: Treating the underlying vascular issues can improve circulation. Toe hair seldom returns, but nobody complains much.
Clues your feet give about your health, 3-4
3. Red flag: Frequent foot cramping (charley horses)
What it means: The sudden stab of a foot cramp -- basically, the hard contraction of a muscle -- can be triggered by fleeting circumstances such as exercise or dehydration. But if it happens often, your diet may lack sufficient calcium, potassium, or magnesium. Pregnant women in the third trimester are especially vulnerable thanks to increased blood volume and reduced circulation to the feet.
More clues: Charley horses tend to rear up out of nowhere, often while you're just lying there. They can be a single sharp muscle spasm or come in waves. Either way, soreness can linger long afterward.
What to do: Try to flex the foot and massage the painful area. You may also be able to relax the muscle by applying a cold pack or rubbing alcohol. To prevent cramps, stretch your feet before you go to bed. Then drink a glass of warm milk (for the calcium).
4. Red flag: A sore that won't heal on the bottom of the foot
What it means: This is a major clue to diabetes. Elevated blood glucose levels lead to nerve damage in the feet -- which means that minor scrapes, cuts, or irritations caused by pressure or friction often go unnoticed, especially by someone who's unaware he has the disease. Untreated, these ulcers can lead to infection, even amputation.
More clues: Oozing, foul-smelling cuts are especially suspect because they've probably been there awhile. Other symptoms of diabetes include persistent thirst, frequent urination, increased fatigue, blurry vision, extreme hunger, and weight loss.
What to do: Get the ulcer treated immediately and see a doctor for a diabetes evaluation. Diabetics need to inspect their feet daily (older people or the obese should have someone do this for them) and see a healthcare professional every three months.