Theres no pain that should be ignored, says Jane Andersen, D.P.M., a podiatrist in Chapel Hill, North Carolina and a member of the American Podiatric Medical Association . Any type of painnew or prolongedwarrants a visit to your primary care doctor or podiatrist. Pain in the feet can signal a host of conditions, from fractures to plantar fasciitis (inflammation in the tissue that connects your heel bone to toes), to arthritis. Noting the time of day when the pain occurs can give you a hint as to the cause.

• Pain in the morning, when you first get up, can point to arthritis or plantar fasciitis. With both conditions, pain will recede as the foot loosens up throughout the day. A common cause of heel pain, plantar fasciitis often affects runners, and people who are overweight. Wearing high heels, or shoes that dont have enough arch support also raises the risk. Dr. Andersen often sees people in her practice whose plantar fasciitis is caused by exercising in worn out shoes. Athletic shoes dont last very long, she says. If you can estimate the mileage you put on shoes, then a good rule of thumb is replacing shoes every 350-500 miles, or anything over a year old, she says.

• Pain that gets worse throughout the day may indicate a fracture, Dr. Philbin says. Pain caused by a fracture will recede when resting and worsen when bearing weight. Fractures, or small cracks in the bone, can be caused by overactivity or changes in activity, like trying a new exercise, according to the AAOS. Osteoporosis or other conditions that weaken bones can up the risk of a fracture. Healing fractures requires immobilizing the foot with a boot, and possibly even surgery.

2. Discoloration

You know to check your body and face for skin cancer, but you probably overlook your feet. However, skin cancer is the most common cancer seen in the foot, says Dr. Andersen. If you see an unusual mole on the top or bottom of your foot or between toes, it should be checked out, she says. If you notice anything - a lump or bump - you should see a podiatrist. Dont forget to check your toenails, too. Melanoma, the most deadly type of skin cancer, can occur as dark spots underneath the nails. If youre not sure whether dark spots are serious or something benign, like dried blood from an injury under your toenail, see your doctorand know that blood under the nail will grow out, while skin cancer will not, Dr. Andersen says.

3. Numbness

Numb feet can indicate a host of serious health problems, from poor circulation to alcoholism. Causes of numbness may include:

• Peripheral artery disease (PAD), a narrowing of the arteries that reduces blood flow, can result in numbness. PAD is also usually accompanied by leg pain and cold lower legs.

• Diabetes affects circulation and blood supply, and numbness is a complication of the disease. Diabetes is a big thing we worry about, Dr. Andersen says. Neuropathy, a complication of nerves most often caused by diabetes, damages the skin and causes diabetics to lose sensation in their feet. Loss of sensation might mean the person cant feel their skin breaking down, which can cause ulcerations, infections, and sometimes severe infections that require amputations, Dr. Andersen says. For many undiagnosed diabetics, neuropathy is often the first sign that they have diabetes, Dr. Philbin says.

• Numbness can also be related to neurological problems, arthritis, or long-standing alcoholism, says Dr. Philbin. Although unknown why severe alcoholism over time can numb arms and legs, its possible that poisoning of the nerves and poor nutrition associated with heavy alcohol use are to blame, according to MedlinePlus, the web site of the U.S. National Library of Medicine.

4. Swelling

While swollen feet can commonly occur after standing for long periods of time, theyre also indicative of some injuries like stress fractures and tendon tears, Dr. Philbin says. Its also possible that something is wrong with the veins or arteries, and theyre not working well enough to control swelling, he says. If you experience excessive swelling in the feet with no history of injury, your podiatrist can check your circulation by feeling your pulses, and doing tests to rule out thyroid problems or other issues. Swelling may also be a reaction to a medication or a sign of congestive heart failure, Dr. Andersen points out.

5. Cold feet

Constantly cold feet may be a result of insufficient blood flow. Poor circulation is a complication of diseases such as PAD, which most often affects men over 50. Risk factors include smoking, high blood pressure, heart disease, and history of stroke. Your podiatrist can check your circulation by feeling for pulses in the feet. Coldness along with toes that turn colors - from white or blue to red - may be due to Raynauds disease, a common condition in which the blood vessels spasm and constrict in response to cold temperatures.