What are white spots on skin?
White spots on the skin appear lighter than your normal skin color. Most of the time we think sun exposure causes extra melanin production and brown spots or a tan to form on the skin. However, exposure to the sun can also cause the skin to stop producing melanin, which causes white spots in those areas.
Sometimes white spots on the skin can also be caused by fungal infections, so it is wise to see your doctor to examine your skin.
Signs and symptoms of white spots on skin
You may not feel anything as white spots on your skin appear. However, signs of white spots on skin from sun exposure include:
- Small spots that are lighter than your normal skin color
- Round or oval-shaped spots
- Irregular-shaped spots
- Feathery-shaped spots
- Petal-shaped spots that look like a flower
- Spots on areas most exposed to sun, including arms, legs, and upper back
- Spots 2 to 6 millimeters in size
- Spots developing slowly over the years
- Spots that do not have a pattern or grouping
- Spots that do not change in size or go away once present
- Spots that are typically smooth
These white spots on skin do not affect the hair follicle or cause the hair to lose its pigment. Also, spots affect men and women differently. For example, many women gain white spots on their skin at younger ages than men.
Most people with small white spots caused by the sun do not feel any symptoms as they develop. These spots are not itchy or inflamed, and are considered harmless. The risk of developing white sun spots increases with age and frequency of unprotected sun exposure.
Causes of white spots on skin
While the exact cause of idiopathic guttate hypomelanosis is unknown, it is thought to be caused by a decrease in melanin production. Exposure to ultraviolet (UV) light causes damage to the skin cells that produce melanin, which gives skin its color.
The decrease in melanin production may also be caused by structural differences in the skin. Idiopathic guttate hypomelanosis tends to run in families, so genetics may also play a role.
Overall, research is still unclear about the exact cause, but sun exposure is thought to be the main factor.
When to see the doctor for white spots on skin
Most of the time, small white spots on the skin are caused by improper sun protection and are considered harmless. However, sometimes the spots may look like other skin conditions, and if so, it may be necessary to see your doctor.
You should see your doctor if the white spots on your skin:
- Provide discomfort
- Itch and are dry
- Appear red or inflamed
- Look like flaky patches that ooze or weep
- Make you feel upset or distressed about your appearance
People who have one autoimmune disease are at risk of developing another. You should talk to your doctor if you have an autoimmune disorder to rule out the development of an autoimmune skin condition like vitiligo or eczema.
People with allergies or asthma may be at risk for developing eczema, which causes dry, itchy, white patches of skin. If you have allergies or asthma and you develop these symptoms, you should see your doctor.
Diagnosis and tests for white spots on skin
Your doctor will diagnose your skin after discussing your personal and family medical history and examining your skin.
Sometimes your doctor may want to do a biopsy of the area. This involves removing a sample of skin to study your skin cells. A doctor may look for a decrease in the amount of skin cells called melanocytes. However, this procedure is usually unnecessary.
Your doctor may also ask for your symptoms to rule out other skin conditions like a fungal infection or an autoimmune condition.
Treatments for white spots on skin
Sun exposure that causes white spots on skin are generally considered harmless. However, some people find the spots visually unpleasant and ask their doctor for treatment. Your doctor may recommend different treatments, including:
- Sunscreen to protect the skin from more damage
- Corticosteroid cream
- Tretinoin retinoid cream
- Pimecrolimus anti-inflammatory cream
- Carbon dioxide laser
- Microneedling via a tattoo machine
Carbon dioxide lasers and cryotherapy may cause swelling and post-inflammatory hyperpigmentation, or darkening in the area. This may be long term and cause more skin problems.
The best treatment for avoiding white sun spots on skin is to protect the skin from the sun. Wear sunscreen daily and avoid tanning beds.