The goal of this clinical trial is to learn if chromium picolinate can reduce the severity of acanthosis nigricans and improve insulin resistance in adolescents with both conditions. It will also learn about the safety of chromium picolinate use in this age group. The main questions it aims to answer are:

1. Does chromium picolinate reduce the severity of acanthosis nigricans as measured by the Burke quantitative scale for acanthosis nigricans severity in adolescents with insulin resistance?
2. Does chromium picolinate improve insulin resistance as measured by the homeostasis model assessment of insulin resistance (HOMA-IR)?
3. What medical problems do participants have when taking chromium picolinate? Researchers will compare chromium picolinate to placebo to see if chromium picolinate is effective in reducing acanthosis nigricans severity and improving insulin resistance.

Participants will:

1. Take chromium picolinate or placebo daily for 24 weeks.
2. Acquire baseline assessment and then visit the clinic at 8 weeks, 16 weeks, and 24 weeks for clinical evaluation, acanthosis nigricans severity assessment using the Burke quantitative scale for acanthosis nigricans severity, laboratory assessment of insulin resistance using the homeostasis model assessment of insulin resistance, and monitoring for any side effects or complications.

Inclusion Criteria:

• Adolescent patients of both sexes, aged 12 to 18 years.
• Clinically diagnosed with acanthosis nigricans.
• Present Insulin resistance, defined as Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) ≥ 2.5.
• Willing to participate in the study, with written informed consent provided by both the patient and guardian.

Exclusion Criteria:

• Diagnosis of type 1 or type 2 diabetes mellitus.
• Known hypersensitivity to chromium or any of the capsule excipients.
• Use of insulin-sensitizing medications (e.g., metformin, thiazolidinediones) within 3 months before screening.
• Use of systemic corticosteroids or other medications known to affect glucose metabolism within 3 months before screening.
• Significant renal disease (estimated glomerular filtration rate < 60 mL/min/1.73 m²) or liver disease (alanine aminotransferase or aspartate aminotransferase > 2.5 times the upper limit of normal).
• Pregnancy or lactation.

De-identified participant-level data, including acanthosis nigricans severity measurements, insulin resistance severity status, baseline demographics, and follow-up data relevant to primary outcomes.

Upon publication of the trial result on open access repository.

Access will be open to researchers and the public via a free, open-access data repository, with a DOI provided in the publication. Data will be de-identified to protect participant privacy.

This is a double-blind study. Participants, and outcome assessors, (Physician and laboratory personnel) will be unaware of treatment assignment. Clinical assessment of acanthosis nigricans severity using the Burke quantitative scale for acanthosis nigricans severity and laboratory assessment of insulin resistance using the homeostasis model assessment of insulin resistance, based on fasting plasma glucose and fasting serum insulin measurements, will be performed without knowledge of treatment allocation. The study medication and placebo will be identical in appearance and packaging. Treatment allocation codes will be securely stored and will be revealed only after completion of data analysis, unless unblinding is required for participant safety.