This is a really interesting question. If you look in a dermatology textbook, there is a small section on “chromoderma.” There are several diseases that can cause the color of the skin to change, and some of them are listed.
Almost all of the problems below need medical attention. The exception is eating too many carrots!
Here are a few reasons for skin color change:
- A yellow color all over – both face and body. Liver or bile duct disease can cause this by increasing certain compounds in the blood. This is called jaundice and is more common than you’d think.
- A light orangey color – usually face and body. Can be caused by taking too much of the supplement beta carotene or drinking or eating a ton of carrots or carrot juice.
- Blue, white, then red (sequence may be different). Usually a problem on the fingers and toes, but sometimes can affect the face or other body parts. Called Raynauds and may be linked to other health problems, in which case it’s referred to as Raynaud’s syndrome.
- Dusky blue color. Can be anywhere, but indicates very poor circulation or heart problems. Seek medical attention right away!
- Persistently red skin. Especially on the face, this may be rosacea, systemic lupus, vascular problems, high blood pressure, medications, and a host of other causes.
- Whiter areas. Spots or larger areas are possible. May indicate the autoimmune skin disease vitiligo. Small spots in sun damaged areas usually indicate sun damage. Hanson’s disease (leprosy) is rare in the U.S., but can cause loss of pigment.
- Green. I know of no reported cases of this!
- Brown blotchy area. Usually on the face, but can occur on arms and other area. When it’s associated with pregnancies and birth control pills, it’s called melasma. Sun damage can also cause this. Certain heart medications, or other medications may also contribute. On the lower legs especially, it may be caused by leaky blood vessels which leaves iron staining in the skin.
Hope this helps! Dr. I