These are the consequences of sleeping with a…

You’ve probably noticed dark patches on the back of your neck that don’t disappear no matter how much you wash or scrub the area. The most common reaction is to think it’s just accumulated dirt, sweat, or poor hygiene. However, when these marks persist and have a particular texture, they could be indicating something much more serious for your health .

This type of skin lesion has a medical name: it’s called acanthosis nigricans . Although it doesn’t pose a serious danger in itself, it can serve as an early warning sign that the body is developing insulin-related problems, which in the long term increases the risk of developing type 2 diabetes.

Acanthosis nigricans is a skin condition characterized by the appearance of areas with three very recognizable features:

Darker in color than the surrounding skin, usually in shades of brown or gray. Thickened texture , thicker than normal skin. Velvety or soft to the touch.

These spots usually appear in body folds, although they can appear in different areas. The most common areas include:

The back and sides of the neck. The armpits. The inguinal region (groin). Under the breasts. Around the elbows and knees. The knuckles of the hands.

Unlike common dirt or dead skin cell buildup, these plaques don’t disappear with washing, exfoliation, or vigorous scrubbing . That’s precisely one of the key indicators for differentiating them from other superficial causes.

Why does this condition occur?

The most common cause of acanthosis nigricans is insulin resistance . Insulin is a hormone produced by the pancreas that allows cells to use glucose from the blood as a source of energy .

When the body becomes less sensitive to this hormone, the pancreas responds by producing increasingly larger amounts of insulin to compensate. These elevated blood levels can stimulate accelerated growth of skin cells, leading to the characteristic thickened, darkened plaques.

In other words, the skin becomes a mirror of what’s happening in the body’s metabolism. Therefore, detecting these spots early can be a valuable opportunity to act before a more serious condition develops.

Several factors increase the likelihood of developing acanthosis nigricans. Among the most important are:

Overweight or obesity : this is the factor most associated with this condition. Prediabetes or type 2 diabetes: alterations in glucose management are directly related. Family history of diabetes: genetics plays a determining role. Hormonal disorders: such as polycystic ovary syndrome (PCOS), which is also related to insulin resistance. Use of certain medications: some drugs, such as corticosteroids or high-dose birth control pills, can promote their appearance. Other medical conditions: In rare cases, it may be associated with endocrine problems or even certain types of tumors. Can flaxen also have it? Yes. Acanthosis nigricans is not exclusive to adults. It is increasingly being detected in children and adolescents, especially those who are overweight or obese . In these cases, the presence of dark patches is considered an important indicator for assessing the risk of type 2 diabetes at an early age, something that was very uncommon decades ago but is now observed more regularly.