What causes moles and how to monitor them?

What are moles?

Moles, also called nevi , are pigmented formations on the skin resulting from the growth of pigment cells called melanocytes.

These skin melanocytes produce a pigment called melanin, which is responsible for the color of skin, hair and eyes. Moles can vary in size, color and shape which can be round or oval , but they are generally brown or black spots that appear on the surface of the skin.


What causes moles?

Most moles form over the course of a person's life, often as a result of exposure to ultraviolet ( UV ) rays from the sun. UV rays can stimulate the production of melanin, causing these small spots to appear on the skin. However, it is important to note that some moles can also be present at birth and are inherited genetically.

Congenital moles, also called congenital nevi, are present from birth or appear shortly afterward. They are not directly linked to exposure to UV rays, because melanin, the pigment responsible for skin color, is already present in the newborn.

Heredity plays an important role in the formation of congenital moles . If parents have moles, it is more likely that their child will also have them at birth. However, although heredity can influence the presence of moles, other complex genetic factors also play a role in their development.

In general, moles are considered benign skin formations and do not require special treatment. However, it is crucial to monitor their progress to detect any potential signs of skin cancers , particularly melanoma .

How to monitor moles and how to recognize a worrying mole?

It is recommended to monitor moles regularly for any changes. When in doubt, it is essential to get screened and consult dermatologists . Vigilance is particularly important in the presence of atypical moles, characterized by irregular edges , uneven color or unusual size.

The ABCDE method is often used to assess the dangerousness of a mole:

  • Asymmetry : Normal moles are usually symmetrical. Any asymmetry should be examined carefully.
  • Edges : Smooth edges are normal, but jagged edges may indicate a problem.
  • Color : A uniform brown color is usual. Color variations may indicate a problem.
  • Diameter : Normal moles are usually less than 6 millimeters in diameter.
  • Evolution : Any change in the size, shape, color or texture of the mole should be reported.

monitor mole

Risk factors for the development of atypical moles

Atypical moles, also called dysplastic nevi, are moles that have unusual characteristics compared to normal moles. Certain risk factors can contribute

  • Family history : People with a family history of melanoma or atypical moles have an increased risk of developing atypical moles. Genetic factors may play a role in predisposition to these types of moles.
  • Exposure to UV rays : Although not all moles are directly linked to sun exposure, UV rays can contribute to the development of atypical moles. Excessive exposure to the sun, especially during childhood and adolescence, is a risk factor.
  • Skin phototype : Individuals with fair skin are generally more likely to develop atypical moles. People with fair skin and blonde or red hair have less melanin to protect the skin from damage caused by UV rays.
  • Personal history of sunburn : Repeated sunburn, especially during childhood, can increase the risk of developing atypical moles. Insufficient sun protection also contributes to this risk.
  • Total number of moles : People with a large number of moles have a potentially higher risk of developing atypical moles. However, the sheer quantity of moles is not the only indicator of risk.
  • Hormonal factors : Certain hormonal changes, such as those occurring during pregnancy, can influence the development of atypical moles.
  • Age : Atypical moles tend to appear most often during the teens and twenties. However, they can develop at any age.

It is essential to note that although these factors may increase the risk, the presence of these factors does not necessarily guarantee the development of atypical moles. Regular monitoring of the skin, recognizing signs of atypia, and consulting a dermatologist if in doubt are important practices to detect and treat any potential problems early.


Monitoring moles on the scalp

Moles can appear on any part of the body, including the scalp. Due to the presence of hair, it may be more difficult to detect changes on the scalp. However, it is essential to monitor this area regularly, especially if sun exposure is frequent. Mirrors and hairdressers can help monitor moles on the scalp.

How to prevent the appearance of moles

Although some factors related to the formation of moles, such as family history and genetics, are uncontrollable, there are preventative measures you can take to reduce the risk of new moles appearing and minimize the risks. linked to these skin formations. Here are some tips to prevent the appearance of moles:

  • Sun protection : Exposure to ultraviolet (UV) rays from the sun is one of the main factors contributing to the formation of moles. Use sunscreen with a high protection factor regularly, even on cloudy days, and avoid excessive exposure to the sun.
  • Avoiding sunburn : Frequent sunburn, especially during childhood, increases the risk of developing atypical moles . Protect yourself from the sun by using protective clothing, hats and seeking shade during the hottest hours of the day.
  • Regular monitoring : Examine your skin regularly for any changes in the size, color, shape or texture of existing moles. Pay particular attention to atypical moles and consult a dermatologist if in doubt.
  • Protective clothing : Wear clothing that covers your skin, especially in hot, sunny weather. Opt for wide-brimmed hats, sunglasses and long-sleeved clothing to minimize sun exposure.
  • Avoid tanning beds : Tanning beds can also contribute to UV damage. Avoid the use of tanning beds to reduce the risk of atypical moles forming.
  • Balanced diet : Certain nutrients, such as antioxidants found in fruits and vegetables, can contribute to skin health. Eat a balanced diet to promote healthy skin.
  • Stress management : Chronic stress can affect skin health. Adopt stress management strategies, such as meditation, yoga, or other relaxing activities.
  • Regular visits to the dermatologist : Regular visits to a dermatologist can help monitor your skin professionally. They can detect and assess atypical moles, provide personalized preventive advice and recommend appropriate measures when necessary.

It is important to note that even by taking these preventative measures, it is not possible to completely eliminate the risk of new moles forming. However, these tips can help minimize risks and maintain healthy skin. If in doubt or if there are suspicious changes to the skin, always consult a healthcare professional.

What is melanoma?

Melanoma is a rare skin cancer , but the number of new cases per year is increasing the most. It is also one of the leading causes of cancer in young people (affected patients are often between 25 and 35 years old).

Melanoma corresponds to the anarchic multiplication of melanocytes (skin cells which produce melanin) which have become cancerous. The tumor most often remains located in the epidermis .

When melanoma is not treated early , it can metastasize and reach other organs. This may warrant treatment with chemotherapy but this is always determined by your doctor.

The risk of developing skin melanoma is greater if you do not take into account the elements we have mentioned in terms of prevention.


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