Collagen supplements are mainly known for their skin health benefits, and whilst there are limited studies that investigate the role of collagen on weight loss, there is some research suggesting that collagen may be of benefit.
So may collagen indirectly promote weight loss?
Yes, research shows that collagen supplements may indirectly impact weight loss by boosting the effect of weight training/resistance training on muscle mass, reducing the development and accumulation of fat cells, regulating fat metabolism, and helping us feel more full.
A 2019 study reported that collagen from the fish, skate, decreases body fat in humans. Whilst the amount of fat lost was quite small this finding indicates potential benefits for weight loss. However, the precise mechanisms behind these findings are uncertain, potentially, it could be that collagen alters gene expression related to how the body accumulates and stores fat. More research is warranted to determine these mechanisms.
Furthermore, another study suggested that collagen supplements may promote fat loss by enhancing the results of resistance training on muscle mass. The participants took part in a 12 week weight training programme, with half the group supplementing with collagen whilst the other half took a a placebo. At the end of the 12 weeks the group who supplemented with collagen showed increased muscle strength, muscle mass, and lost more body fat compared with the group who took the placebo.
Collagen supplements may also help weight loss by making us feel more full, thus reducing hunger, and how much you end up eating. Whilst more research is needed in this area, this effect may because of the fact that collagen is a protein. Studies have shown that higher protein diets suppresses the hunger hormone, ghrelin, whilst promoting the hormones that control satiety, such as glucagon-like peptide-1 and cholescystokinin. Win-win!
So whilst this research is very much preliminary, supplementing with collagen could potentially be helpful and beneficial for weight loss.