Background: Hepatic steatosis, commonly referred to as non-alcoholic fatty liver disease (NAFLD), was once regarded as a harmless condition. However, it has recently garnered considerable attention due to its links with insulin resistance syndrome, type 2 diabetes mellitus, and heart disease. Alanine aminotransferase, a liver enzyme frequently elevated in NAFLD, serves as a common marker for the condition. Objective: To assess ALT's role in NAFLD and its link to metabolic syndrome, diabetes, cardiovascular disease, and management strategies. Results: Several cross-sectional and cohort investigations have revealed a link between increased ALT levels and characteristics of the metabolic syndrome, as well as type 2 diabetes mellitus. ALT has emerged as a promising indicator for NAFLD and its advancement. Moreover, therapeutic approaches focusing on weight reduction, physical activity, and targeted medications have proven effective in decreasing liver fat accumulation, enhancing ALT levels, and consequently mitigating related cardiovascular risks. Conclusion: ALT is a key marker for NAFLD, linked to type 2 diabetes, metabolic syndrome, and heart disease. Reducing hepatic fat as well as managing cardiovascular risks are vital for addressing NAFLD and its complications, with ALT serving as a valuable tool for monitoring treatment effectiveness and guiding clinical decisions.