Obesity poses a significant health danger. The effects of green coffee extract (GCE) and turbo slim blue (TSB) on decreasing the body weight (BW) and their impact on various physiological indicators of metabolic state in obese rats were investigated in this study. Twenty-one male rats weighing 320-360 g were distributed into three groups. Rats were treated with the following for 4 weeks: distilled water (control), GCE (10 mg/kg), and TSB (10 mg/kg). All measurements are percent (%) BW changes, pancreatic function markers (insulin, glucose, HOMA-IR), protein, and lipid indicators. Thyroid hormones, leptin, testosterone, liver, and renal function markers were also measured. Relative to the control group, GCE-treated rats significantly reduced the % of the change in BW, glucose, HOMA-IR, and leptin. GCE significantly increases T3 and T4. In addition, GCE-treated rats showed decreased serum lipids and increased serum testosterone levels. Biomarkers of protein metabolism, liver, and kidney function were unaffected by GCE. In contrast to GCE, the loss of BW induced by TSB is associated with a significant rise in liver and kidney function, which is a marker of toxicity. Therefore, GCE can be considered as a harmless and effective additional therapy to reduce BW.