I have set in dirt on my neck ive had it since i can remember... i know it is dirt from poor hygiene as a kid?

May not be dirt: You can have a darkened area at the base of the back of your neck as part of insulin resistance, an early sign of type 2 diabetes. I would have this checked.

Not dirt : Dirt washes off . You may have acanthosis nigricans. It looks like dirty skin but is a finding that is associated with insulin resistance- a pre-diabetic State. Ask you doctor to check a glucose /insulin ratio and if abnormal you may benefit from metformin Plus diet and exercise .

Not dirt : Dirt washes off . You may have acanthosis nigricans. It looks like dirty skin but is a finding that is associated with insulin resistance- a pre-diabetic State. Ask you doctor to check a glucose /insulin ratio and if abnormal you may benefit from metformin Plus diet and exercise .