Collagen supplementation and weight gain
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Collagen Supplementation and Body Weight: Effects on Weight Gain and Fat Mass
Collagen Supplementation and Body Fat Reduction
Multiple studies show that collagen supplementation does not cause weight gain; instead, it is often linked to reductions in body fat and improvements in body composition. In randomized controlled trials, collagen peptide supplementation (typically 15–20 g per day for 12 weeks) led to significant decreases in total body fat mass and percent body fat in older adults and people with overweight or obesity, without increasing overall body weight or fat mass 347. These effects were observed even when participants maintained their usual physical activity and dietary habits .
Collagen and Fat-Free Mass (Muscle Mass)
Collagen supplementation, especially when combined with resistance training, has been shown to increase fat-free mass (muscle mass) and strength in both older adults and younger, recreationally active men 159. These increases in muscle mass did not come with increases in fat mass, and in some cases, fat mass was reduced 179. Meta-analyses confirm that collagen peptide supplementation is associated with significant improvements in fat-free mass and muscle strength, particularly when paired with exercise 79.
Collagen’s Role in Appetite and Satiety
Some forms of collagen, especially those with high swelling capacity, may help reduce hunger and increase feelings of fullness, which can contribute to lower calorie intake and weight loss . In human trials, participants reported reduced hunger and increased satisfaction after collagen supplementation, which may help explain the observed reductions in body weight and fat mass .
Collagen and Obesity Prevention in Animal Studies
Animal studies support these findings, showing that collagen hydrolysate supplementation can reduce body weight gain and fat accumulation in models of estrogen deficiency (such as menopause) and high-fat diet-induced obesity 268. Collagen peptides were found to inhibit the formation of new fat cells and reduce the size of existing fat cells, as well as improve blood lipid profiles 26. Additionally, collagen peptides may positively influence gut microbiota, which is linked to reduced obesity risk .
Collagen Supplementation and Overall Body Weight
While collagen supplementation can increase muscle mass (which may slightly increase total body weight in some cases), the overall effect is a healthier body composition with more muscle and less fat 159. In studies where body weight increased, it was due to gains in fat-free mass, not fat mass 15. In most cases, collagen supplementation either reduced body weight or had no significant effect on weight gain 234678.
Conclusion
Current research consistently shows that collagen supplementation does not cause weight gain through increased fat mass. Instead, it is associated with reductions in body fat, increases in muscle mass, and improved body composition, especially when combined with resistance training. Collagen may also help control appetite and support healthy weight management, making it a promising supplement for those looking to improve body composition and prevent obesity.
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