In most cases, visible veins aren’t a cause for concern. Exercise, hot weather, sun exposure, and tight clothing can make your veins more noticeable. Aging, genetics, and being overweight may also increase their definition.

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Veins are blood vessels that bring deoxygenated blood back to the heart. They’re different from arteries, which bring oxygenated blood from your heart to your body.

If you have a lighter skin tone, it may be normal to have some visible veins. However, certain things can make your veins look even more obvious in terms of color and size.

It might be more difficult to see the color of your veins if you have a darker skin tone. But if they become more visible, their size might be more noticeable.

Most causes of visible veins are temporary and benign. Some causes, like blood clots, are medical emergencies.

Learn about the possible reasons of suddenly visible veins, along with treatment options.

Possible causes of visible veins include:


During exercise, your blood pressure increases. This can widen your veins, making them look more obvious.

Also, when your muscles contract during exercise, they place pressure on surrounding veins. This is especially common during lifting.

Tight clothing

Tight clothing can restrict blood flow. In turn, the blood pressure in your veins can increase, making them more visible. This often happens in the waist, thighs, and legs.


Hot weather also increases blood flow in the veins, enhancing their definition.

Sun exposure

Collagen is a protein that gives structure to your skin. Excess sun exposure can break down collagen beneath the skin, making your veins more noticeable.

Sitting or standing for a long time

When you sit or stand for a long time, gravity causes blood to pool in your legs. As a result, blood pressure increases in the leg veins and increases their definition.

Skin color

If you have a fair complexion, the color of your veins might be more visible.

Your weight

Being overweight or having obesity places pressure on your veins. The excess pressure can enhance vein definition, especially in the legs.


Sometimes, visible veins run in families. If you have a family history of visible veins or conditions that affect the wall of your veins, you might be more likely to have it, too.

Hormonal changes

Hormonal changes can also alter the appearance of your veins. This includes:

  • puberty
  • menstruation
  • pregnancy
  • birth control pills
  • menopausal hormone therapy

Specifically, during pregnancy, a fetus places pressure on the veins in the pelvis area. This can increase pressure in the veins of your thighs, buttocks, and legs.

Also, blood flow increases to support the fetus during pregnancy, making veins swell.


As you get older, your skin makes less collagen, resulting in thin skin. Your body also loses fatty tissue. These changes can make your veins easier to see.

Drinking alcohol and smoking cigarettes

Drinking alcohol can make visible veins even more noticeable. Alcohol raises your heart rate, placing extra pressure on your veins.

Cigarette smoking injures the walls of your veins, making them bulge and be more visible.

Underlying medical condition that causes swollen veins

Certain medical conditions can cause swollen veins.

  • Varicose veins. Varicose veins happen when groups of purple veins become chronically swollen. It can be worsened by many things on this list, like drinking alcohol and prolonged standing.
  • Chronic venous insufficiency. Chronic venous insufficiency is when the valves in your veins don’t allow for proper blood flow. This causes blood to collect in your legs.
  • Superficial thrombophlebitis. This condition occurs when a vein near the skin is inflamed and swollen. It can be caused by a superficial blood clot, trauma, cancer and some cancer treatments, or prolonged sitting.

Chronic constipation

Chronic constipation places pressure in the abdominal area, which increases pressure on nearby veins.

Blood clot

A blood clot in a vein can cause a condition called deep vein thrombosis, which often affects the leg. The blood clot can block blood flow in the vein, increasing blood pressure. The vein may look more noticeable.

Blood clots are a medical emergency

If the blood clot breaks loose, it can travel to your lungs and cause a blockage known as pulmonary embolism. Call 911 if you have:

  • hard, swollen veins
  • pain or swelling in one leg
  • warm skin on the painful leg
  • darkened or red skin on the affected leg

Possible causes of suddenly swollen veins in the hands include:

  • exercise
  • hot weather
  • sun exposure
  • light skin color
  • aging
  • hormonal changes, including pregnancy
  • genetics
  • underlying conditions that cause swollen veins
  • blood clot in the hands or arms

On your chest, veins may become suddenly visible due to:

  • exercise
  • hot weather
  • sun exposure
  • wearing tight clothing
  • light skin color
  • aging
  • hormonal changes, including pregnancy
  • breastfeeding
  • genetics
  • underlying conditions that cause swollen veins

In children, visible veins might be due to:

  • exercise
  • hot weather
  • sun exposure
  • wearing tight clothing
  • being overweight or having obesity
  • light skin color
  • hormonal changes (puberty)
  • genetics

Other possible causes include:

  • Scleroderma. Scleroderma is a condition that affects connective tissue growth. It can cause spider veins, along with scarring and sores.
  • Klippel-Trenaunay syndrome. This is a rare congenital disorder that causes varicose veins in a limb. The affected limb may also be enlarged or shorter than normal.
  • Vascular Ehlers-Danlos syndrome. This connective tissue disorder causes thin skin, making veins more visible. However, this might be harder to see in children with darker skin tones.

If you’re concerned about the appearance of your child’s veins, see their doctor.

If your veins are visible for a long time and you’re not sure why, see a doctor. You should also seek medical help if you have:

  • visible veins that cause pain
  • veins that are red or swollen
  • veins that feel warm
  • skin rash, sores, or discoloration on your legs
  • a bleeding vein
  • difficulty moving or doing daily activities

If your veins are visible due to a non-medical cause, treatment involves lifestyle changes. Here’s what you should do if visible veins are caused by:

  • Exercise: Take a break and rest.
  • Hot weather or sun exposure: Find shade to cool down.
  • Tight clothing: Change into looser clothing.
  • Prolonged sitting or standing: Change your position to avoid sitting or standing too long.
  • Being overweight or having obesity: Work with a doctor to create a weight loss plan.

Treatments for medical causes include:

Compression stockings

Compression stockings can help improve blood flow in your legs. This option is usually recommended for mildly visible veins.

Anti-coagulant medication

If your visible veins are due to deep vein thrombosis, you may need to take anti-coagulant drugs, or blood thinners. A doctor might give you an injection, oral tablets, or both.

Nonsurgical treatments

Nonsurgical procedures may include:

  • Sclerotherapy. Sclerotherapy involves injecting a chemical into your veins. This seals the vein and turns it into scar tissue, causing the vein to fade.
  • Closure system. In this treatment, a sticky substance is injected into the visible vein. The substance closes the vein and prevents blood flow, helping the vein look less noticeable.
  • Percutaneous laser treatment. This nonsurgical treatment uses lasers, or intense bursts of light. The laser travels through the skin and closes the vein, making it fade.
  • Endovenous thermal therapy. In this procedure, a small probe is inserted into the vein. The probe closes the vein with heat, then seals it with laser or radio waves.


Surgery might be required for very large veins. Options include:

  • Ambulatory phlebectomy. During this procedure, veins just under the skin are removed with hooks.
  • Surgical ligation and stripping. This surgery involves cutting off the affected vein, then removing it through small incisions made in the skin.

In most cases, visible veins aren’t a cause for concern. Exercise, hot weather, sun exposure, and tight clothing can make your veins more noticeable. Aging, genetics, and being overweight may also increase their definition.

Diseases that affect the vein are more serious. This includes blood clots and deep vein thrombosis. If you suspect you have a blood clot, get medical help immediately.