The skin around a person’s knees may suddenly become darker color. This often results from an increase in melanin. Also known as hyperpigmentation, this usually occurs due to irritation or injury.

Melanin causes dark knees and other dark areas on the skin. Melanin is a pigment in the skin that determines the color of a person’s skin and hair.

This article discusses the causes of dark knees, home treatment options, prevention, and when to see a doctor.

A close up of a person's knees. The person has fair skin and darker-colored knees.Share on Pinterest
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Several conditions can cause the body to produce more melanin around the knees. When the body produces more than normal amounts of melanin, the condition is known as hyperpigmentation.

According to older research published in The Journal of Clinical and Aesthetic Dermatology, inflammation from skin irritation and injury is the most likely cause of hyperpigmentation in people with darker skin tones.

Though the condition is most common in people with darker skin tones, anyone can develop darker skin around the knees.

Skin pigmentation varies from person to person, and many people may naturally have darker knees with no medical cause for concern.

However, if a person wants to reduce the pigmentation in their knees for personal aesthetic reasons, there are a few home remedies that may help. However, they may not work for everyone.

It is important to note that researchers have not studied these remedies in enough detail to draw any firm conclusions. Scientists need to do more research to investigate effective ways to lighten dark knees.

The following are some potentially effective, home-based treatments for dark knees.

Turmeric

People often use turmeric as a spice, and it may have some potential health benefits. One benefit is that it provides curcumin.

In a 2012 study, researchers looked at curcumin as a potential natural treatment for lightening skin. They discovered that turmeric helped block the processes that caused the extra pigmentation.

It is possible that using a homemade cream containing turmeric may help lighten the knees if a person applies it topically.

Green tea extracts

Green tea is another potential skin lightening agent. It contains a compound called epigallocatechin gallate (EGCG).

In a study from 2015, researchers found that EGCG helped prevent the creation of enzymes responsible for making melanin. Therefore, using a green tea extract in a homemade ointment may help lighten the skin.

However, there is not much research to support this use. Scientists will need to conduct more research to confirm the skin-lightening effects of green tea extract on skin pigmentation.

Black tea extracts

Applying black tea to the skin may also lighten it. One 2011 study looked at the effectiveness of black tea extract on hyperpigmentation in brown-skinned guinea pigs.

Researchers applied black tea extract directly onto artificially hyperpigmented spots on the guinea pigs’ skin and found that it significantly lightened these spots.

As a result, the researchers concluded that black tea extract prevented melanin proliferation in the guinea pigs and lightened darkened areas of their skin.

A later test-tube study in 2015 supported these findings. It showed that black tea extract applied to mouse melanocyte skin cells prevented melanin production and synthesis.

The researchers concluded that black tea extract might be a useful skin lightening agent for the cosmetic industry to consider for further research.

It is important to note that researchers did these studies in animals and test tubes, respectively, not in humans. Therefore, scientists need to carry out more research in humans to investigate how black tea may affect skin pigmentation.

While there is not much research to back its effectiveness, an ointment containing black tea extracts may help lighten the skin.

Aloe vera

Many people use aloe vera to relieve skin following sunburn or another minor skin irritation.

Aloe vera may also help lighten a person’s skin. In an older study, researchers found that applying aloe vera to people’s skin helped reduce the darkening effects of sun exposure.

Researchers did this experiment in humans, so it provides some sound evidence. However, the study is from 2002, and scientists need to do more research into the effects of aloe in lessening skin darkening from sun exposure.

A person can find aloe vera cream and ointment over the counter (OTC) at nearly any pharmacy or online.

A person can take some steps to prevent hyperpigmentation on the knees, such as:

  • applying daily moisturizer to keep the skin soft
  • using sunscreen to exposed legs to help prevent sun damage
  • avoiding activities that may damage the skin through friction or chafing

Dark knees will not cause any additional symptoms and are not likely the result of any underlying medical condition. Therefore, a person with dark knees may not need to see a doctor.

However, a person may wish to speak to their doctor if the darkened skin causes them anxiety, feelings of embarrassment, or other stress. A doctor may be able to recommend OTC or prescription creams to help.

If other symptoms accompany the darkened knees, such as itching, scabs, or flaking, a person may want to talk to their doctor.

The darkened skin may be due to psoriasis or another skin condition. Treatment for these conditions may help lighten the skin.

Dark knees are the result of more melanin in the knees than the rest of the body. Sun damage, friction, or wear and tear may cause this.

Dark knees are not a medical risk and are not usually a cause for concern.

However, if a person wants to try lightening their knees for aesthetic reasons, they can try several different methods to treat their pigmentation at home.

It is important to note that scientists have not studied these methods thoroughly in humans, and it is possible that a person will not get the results they want.

A person interested in lightening their knees can ask their doctor for recommendations.