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Several other conditions may create a similar appearance.
One example is Terra Firma-Forme Dermatosis (TFFD), a harmless skin condition that can cause brown or black patches that resemble dirt or pigmentation.
Unlike acanthosis nigricans, TFFD may improve with gentle cleansing using isopropyl alcohol under medical guidance.
Other possible causes include:
- Friction from clothing
- Eczema
- Hormonal disorders
- Certain medications
- Skin pigmentation disorders
Because multiple conditions can appear similar, self-diagnosis should be avoided whenever possible.
Should You Check Your Blood Sugar Levels?
If persistent dark patches appear suddenly or continue to worsen, a healthcare professional may recommend checking blood glucose levels, especially if other risk factors are present.
Additional symptoms that can accompany elevated blood sugar include:
- Increased thirst
- Frequent urination
- Unexplained fatigue
- Blurred vision
- Increased hunger
- Slow wound healing
Blood sugar testing can usually be performed at clinics, pharmacies, or using home glucose monitoring devices.
Risk Factors for Insulin Resistance and Type 2 Diabetes
Several factors may increase the likelihood of developing insulin resistance:
- Excess body weight
- Lack of physical activity
- Family history of diabetes
- High blood pressure
- Poor dietary habits
- Polycystic ovary syndrome (PCOS)
Early identification of risk factors often allows for lifestyle changes that may significantly reduce future complications.