High saturated fat intake was associated with increased IL-6 levels (odds ratio = 2.03, 95% confidence interval [CI] = 1.00–4.11, p < 0.047), whereas high total fat intake elevated leptin levels by 2.14-fold (95% CI = 1.12–4.10, p < 0.021) in participants with obesity. Here, IL6 is linked to obesity due to melanocortin 4 receptor deficiency.