Tamoxifen, a common treatment for estrogen receptor (ER)‑positive breast cancer, is associated with an increased risk of developing nonalcoholic fatty liver disease (NAFLD). Curcumin, a compound in turmeric, has shown potential in mitigating liver disease progression. This study aims to evaluate the efficacy and safety of curcumin in preventing NAFLD in breast cancer patients initiating tamoxifen therapy.In this 6‑month triple‑blind, randomized placebo‑controlled trial, 44 ER+ breast cancer patients scheduled to receive tamoxifen were assigned to receive either curcumin (500 mg daily) or a placebo. NAFLD grade was assessed via ultrasound at baseline and after 6 months. Laboratory values and demographic data were collected, and adverse effects were monitored. Statistical analyses was performed using SPSS version 16.Data of a total of 44 participants (22 participants in each group, mean age: 47.1 ± 6.0 years) were analyses. There were no significant differences between the placebo and curcumin groups regarding the demographic and baseline laboratory values. At study completion, significantly fewer patients in the curcumin group showed an increased NAFLD grade compared to the placebo group (13.6% vs. 54.5%
p = 0.03). Additionally, the prevalence of NAFLD grade ≥ 2 was lower in the curcumin group (13.6% vs. 40.9%
p = 0.04). No adverse effects related to curcumin were reported. Curcumin supplementation demonstrated a protective effect against tamoxifen‑induced NAFLD in ER+ breast cancer patients, suggesting its potential as a prophylactic adjunct to tamoxifen therapy. Larger multi‑centric trials are warranted to confirm these findings.