Effect of Oral Ingestion of Low-Molecular Collagen Peptides Derived from Skate (Raja Kenojei) Skin on Body Fat in Overweight Adults: A Randomized, Double-Blind, Placebo-Controlled Trial

Recent animal studies found the potential of a collagen peptide derived from skate skin to have anti-obesity effects through the suppression of fat accumulation and regulation of lipid metabolism. However, no studies have yet been performed in humans. Here, this very first human randomized, placebo-controlled, and double-blinded study was designed to investigate the efficacy and tolerability of skate skin collagen peptides (SCP) for the reduction of body fat in overweight adults. Ninety healthy volunteers (17 men) aged 41.2 +/- 10.4 years with a mean body mass index of 25.6 +/- 1.9 kg/m(2) were assigned to the intervention group (IG), which received 2000 mg of SCP per day or to the control group (CG) given the placebo for 12 weeks and 81 (90%) participants completed the study. Changes in body fat were evaluated using dual energy X-ray absorptiometry as a primary efficacy endpoint. After 12 weeks of the trial, the percentage of body fat and body fat mass (kg) in IG were found to be significantly better than those of subjects in CG (-1.2% vs. 2.7%, p = 0.024 and -1.2 kg vs. 0.3 kg, p = 0.025). Application of SCP was well tolerated and no notable adverse effect was reported from both groups. These results suggest the beneficial potential of SCP in the reduction of body fat in overweight adults.