Recently, coffee leaf infusion was authorized as a novel food by the European Commission. Little information is available on the bioactive profile and health-promoting benefits of this authorized novel food. Chlorogenic acid (CGA), a multifunctional health-promoting compound (antioxidant, hypolipemiant, antidiabetic) that is found in the different botanical parts of coffee, has been detected in its leaves and infusion. Body fat accumulation is linked to overweight and obesity, one of the major health problems associated with other pathologies, in which oxidative processes are involved. This research aimed to provide new information on the effect of CGA, coffee leaf infusions, and coffee leaf infusion waste on body fat accumulation, using a C. elegans animal model. Coffee leaf infusions were prepared according to the EFSA guidelines. After the infusion preparation, the soluble and insoluble fractions were separated. The insoluble fraction, i.e., the waste, was dried in an oven (40ºC, 3 hours). The antioxidant capacities of the infusion (0.360) and waste (0.083) were determined using ABTS, expressed as mg CGA/ml. The effect of CGA, coffee leaf infusion, and waste on body fat accumulation with a standard diet was analyzed in C. elegans by means of Oil-Red-O staining. CGA (135, 5 and 2.5 µg/ml) and waste (20 µg/ml) significantly reduced (p<0.05) body fat accumulation in nematodes with a standard diet, both qualitatively (images) and quantitatively (staining intensity/body nematode area). The infusion (100 and 50 µg/ml) did not show this effect despite exhibiting a higher antioxidant capacity. The infusion waste contains dietary fiber and phenolic compounds, which could synergistically contribute to the reduction in body fat accumulation. The use of waste could promote the control of body fat accumulation in the consumption of a standard diet and contribute to the Zero Waste goal. The waste containing nutrients could be used a as sustainable and health-promoting food ingredient. The infusion preparation can be improved to obtain an antioxidant beverage for reducing body fat accumulation.