Dark patches on the skin are not always simple dirt that can be removed with soap or scrubbing. In some cases, they may be linked to a condition called Acanthosis Nigricans, which can be an early warning sign of diabetes. A medical doctor on social media, @fiezanizmohamed, raised awareness about this issue, warning people to pay attention to changes on the back of the neck, especially in children and close family members.

She explained, “Try looking out for the dark patches like these on the back of the necks of your children, siblings, or friends. This isn’t a mere accumulation of dead skin cells, this is acanthosis nigricans, one of the early signs of getting diabetes!” She also advised that these marks cannot simply be scrubbed away and that people should consider checking their blood sugar levels if they notice them.

Acanthosis nigricans is a skin condition where areas of skin become darker, thicker, and have a velvety texture. It usually appears in body folds such as the neck, armpits, and groin. These changes are more common in people who are obese or already have diabetes.

Children who show these signs, especially those who are overweight, may have a higher risk of developing type 2 diabetes later in life. This makes early recognition important so that lifestyle changes and medical checks can be done sooner.

The dark patches are often described as “velvety” and sometimes slightly raised or textured. They do not disappear with strong scrubbing or washing, which helps distinguish them from regular dirt. In some cases, similar marks can also appear under the arms, not just on the neck.