Vein problems have probably existed since man started walking upright on two legs. The complaints for which people most commonly seek treatment are varicose veins and spider veins.

Veins in the legs carry the blood away from the limbs toward the heart. To counteract the pull of gravity, valves keep the blood flowing in the right direction. Standing or sitting for long periods exerts pressure on the veins, and if the valves are leaky, the blood will back up and pool, causing the veins to dilate. Varicose veins show up as unsightly bluish bulges under the superficial skin layer. They can cause a variety of symptoms, from aching and swelling to painful blood clots and even ulcers. (When blood flow to the skin is interrupted, skin tissue may die, leaving ulcers, or sores.)

Spider veins show up as thread-like lines near the surface of the skin. Like varicose veins, they are caused by pressure and faulty circulation in the deeper veins. Unlike varicose veins, spider veins are not hereditary. Most at risk for developing them are post-partum women and pre-menopausal and menopausal women with lowered estrogen levels. (Without estrogen, capillaries can become fragile.)

Even women with no family history of varicose veins may develop them during pregnancy, when the uterus exerts pressure on the pelvic veins. Aside from heredity and pregnancy, certain other factors put you at risk for vein problems:

• Gender. Women tend to have more circulatory problems in the legs than men, as they have less muscle mass for pumping blood through the veins.

• Obesity

• Hormonal changes at menopause

• A history of vein disease, such as thrombophlebitis

• Activities that require standing or sitting for long periods. Although standing or sitting in itself does not cause varicose veins, it tends to make them worse in people who already have minor vein problems. Sitting causes the veins to crimp and can lead to life-threatening blood clots. (This is why air travelers are strongly urged to get up and walk about during the flight.)

Treatment for varicose veins goes back to antiquity. The Greek physician Galen described a very crude and barbaric way of stripping the veins - tearing them out of the leg. Until recently the favored method of treatment hadn't changed much. It consisted of surgically removing the veins, then wrapping the legs in compression stockings to stop the bleeding.

What a world of difference the laser has made. It is now possible to treat even the most unsightly veins in less than an hour with a procedure called "laser vein ablation." A laser catheter is inserted into the vein via two tiny incisions - one at the ankle, the other at the groin - then positioned using ultrasound. Once the catheter is in place, the laser is turned on and pulled through the vein cavity. The laser energy destroys the inside of the damaged vein. The result is the same as with surgical removal, but there is much less trauma to the body. Destroying the varicose vein also deflates the surface veins, which can then be removed safely with very tiny incisions. The incisions usually heal spontaneously, without suturing. In some cases, once the varicose veins are treated, the spider veins clear up without any intervention.

Laser energy can also be used to treat spider veins. The laser light coagulates the blood and obliterates the veins. Another effective treatment for spider veins is injection sclerotherapy: An irritating liquid, usually a saline (salt) solution, is injected into the vein with a very fine needle, causing it to collapse and disappear.

When surgery was the preferred treatment for varicose veins, recovery was a lengthy and uncomfortable process. Now, in most cases, you can walk out of the doctor's office after the procedure and return to your daily routine several hours later, without any discomfort.

Short of lasers, there are a variety of measures you can take to relieve the symptoms of varicose veins. Compression stockings are the first line of treatment. Compression squeezes the veins flat so that the blood in your legs doesn't pool and pressure doesn't build up. Compression stockings are particularly important during pregnancy, when the uterus pressing against the pelvic veins causes poor blood flow. Before fitting you for compression stockings, your doctor will rule out arterial vascular disease, which can be made worse by compression of the veins.

Like compression, elevating the legs counteracts the tendency of blood to pool. It can also relieve swelling of the legs caused by lymph fluid leaking out of the dilated veins into the surrounding tissue. Walking is very good for circulation and improves blood flow in the legs. Regular moisturizing of the legs is important to prevent skin breakdown, eczema, and infection - all problems associated with varicose veins.

A variety of herbal supplements and homeopathic remedies are sometimes suggested for general vein health, but there is no evidence these substances protect against the development of varicose veins.

There are, however, a number of measures you can take to prevent varicose veins or keep them from growing worse:

• Keep your weight down.

• Eat high-fiber foods, especially fresh fruits and vegetables.

• Maintain regularity; constipation contributes to poor leg-vein health.

• Cut your salt intake.

• Don't wear clothing that constricts your legs, groin area, or waist.

• Wear elastic support hose (compression stockings).

• Avoid standing for long periods of time. If you must stand, shift your weigh from one leg to the other.

• Don't cross your legs when sitting.

• When sitting for prolonged periods, stand up and move about every 45 minutes.

• Exercise regularly; walking is a good choice.

• Do leg exercises:

• Sit with your legs extended and your feet a few inches above the floor. Rotate both feet at the ankles, first in one direction and then the other. Repeat 4-5 times in each direction.

• With legs extended, flex your feet, pointing your toes toward the ceiling. Hold for a count of 10. Release and point your toes toward the floor. Hold for a count of 10. Repeat the sequence 4-5 times.