Does whey protein make you gain weight
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Does Whey Protein Make You Gain Weight?
Whey protein is a popular supplement among athletes and fitness enthusiasts, but its effects on body weight are complex and can vary depending on several factors. This article synthesizes findings from multiple studies to provide a comprehensive understanding of how whey protein impacts weight gain.
Whey Protein and Muscle Weight Gain
Muscle Growth and Antioxidant Properties
Whey protein has been shown to support muscle weight gain, particularly when combined with resistance exercise. In a study involving rats, whey protein supplementation led to higher muscle and body weight gains compared to a control group. This effect was partly attributed to the antioxidant properties of whey protein, which helped mitigate oxidative stress induced by high-intensity exercise1.
Whey Protein and Fat Loss
Reduction in Body Fat and Food Intake
Several studies indicate that whey protein can contribute to fat loss. For instance, a study on rats demonstrated that those fed a high-protein whey diet had lower body fat and body weight gain compared to those on a control diet. This was associated with decreased food intake and increased fat oxidation4. Another study found that whey protein reduced body weight gain in mice fed a high-fat diet, particularly during the initial weeks of the intervention6.
Impact on Adipose Tissue and Metabolic Health
Whey protein also appears to influence fat distribution and metabolic health. In a study on mice, whey protein was more effective than soy protein in preventing obesity by activating brown adipose tissue and promoting the browning of white adipose tissue. This led to lower body weight and improved metabolic markers such as insulin and cholesterol levels3.
Whey Protein and Weight Gain in High-Fat Diets
Temporary Weight Gain Reduction
Interestingly, whey protein can have different effects depending on the dietary context. In young mice fed a high-fat diet, whey protein initially reduced weight gain, but this effect was temporary. Over time, the weight gain in the whey protein group was similar to that in the control group, although whey protein continued to improve insulin sensitivity and reduce plasma cholesterol levels2 6.
Whey Peptides and Weight Gain
However, not all forms of whey protein have the same effects. Whey protein hydrolysate (WPH), a more processed form of whey, was found to exacerbate weight gain and impair glucose homeostasis in mice fed a high-fat diet. This was associated with increased inflammation and ectopic fat accumulation in the liver and skeletal muscle5.
Comparative Effects of Whey Protein Forms
Concentrated, Hydrolyzed, and Isolated Whey Protein
A meta-analysis comparing different forms of whey protein (concentrated, hydrolyzed, and isolated) found that whey protein supplementation generally led to fat mass loss but did not significantly affect fat-free mass gain. This suggests that while whey protein can help reduce body fat, its impact on muscle mass may be limited7.
Conclusion
In summary, whey protein can both support muscle weight gain and contribute to fat loss, particularly when combined with resistance exercise. Its effects on body weight are influenced by factors such as the form of whey protein used and the overall dietary context. While whey protein can initially reduce weight gain in high-fat diets, its long-term effects may vary. Therefore, individuals looking to manage their weight with whey protein should consider these factors and possibly consult with a healthcare professional for personalized advice.
Sources and full results
Most relevant research papers on this topic
Whey protein increases muscle weight gain through inhibition of oxidative effects induced by resistance exercise in rats.
Whey protein ingestion can increase muscle weight gain in rats by inhibiting oxidative effects induced by resistance exercise.
RCT
Animal StudyWhey-reduced weight gain is associated with a temporary growth reduction in young mice fed a high-fat diet.
Whey protein isolate reduces early weight gain and growth in young mice fed a high-fat diet, but this effect is not explained by food intake, energy expenditure, urea production, or urea cycle activity.
Whey protein and soy protein prevent obesity by upregulating uncoupling protein 1 to activate brown adipose tissue and promote white adipose tissue browning in high-fat diet-fed mice.
Whey protein effectively prevents obesity in mice by suppressing lipogenesis, activating brown adipose tissue, and promoting browning of white adipose tissue, while lowering the protein to carbohydrate ratio.
RCTAnimal StudyDietary Whey Protein Decreases Food Intake and Body Fat in Rats
Dietary whey protein and soy protein both decrease body fat accumulation and weight gain in rats, with different mechanisms contributing to these effects.
RCTAnimal Study
Very Rigorous JournalWhey peptides exacerbate body weight gain and perturb systemic glucose and tissue lipid metabolism in male high-fat fed mice.
Whey protein hydrolysate (WPH) exacerbates high-fat diet-induced body weight gain and impairs glucose homeostasis, with increased inflammation, ectopic fat accumulation, and mitochondrial dysfunction.
Whey Protein Reduces Early Life Weight Gain in Mice Fed a High-Fat Diet
Whey protein initially reduces weight gain in young mice fed a high-fat diet, but the effect on weight gain ceases, it improves glucose tolerance, insulin sensitivity, and reduces plasma cholesterol.
Rigorous JournalComparative Meta-Analysis of the Effect of Concentrated, Hydrolyzed, and Isolated Whey Protein Supplementation on Body Composition of Physical Activity Practitioners
Whey protein supplementation significantly reduces fat mass in regular physical activity practitioners, but has no significant effect on fat-free mass gain.
Meta-AnalysisVery Rigorous JournalTimed-daily ingestion of whey protein and exercise training reduces visceral adipose tissue mass and improves insulin resistance: the PRISE study.
Timed-daily whey protein and exercise training effectively reduce visceral adipose tissue mass and improve insulin resistance in overweight/obese adults, regardless of caloric restriction.
RCTProtein quality and quantity influence the effect of dietary fat on weight gain and tissue partitioning via host-microbiota changes.
High casein intake exacerbates negative metabolic effects of high fat intake, while high whey intake reduces them, primarily through effects on gut microbiota.
Non-RCTAnimal StudyRigorous JournalEffect of dairy proteins on appetite, energy expenditure, body weight, and composition: a review of the evidence from controlled clinical trials.
Whey is more satiating in the short term, while casein is more satiating in the long term, but no clear evidence suggests that one protein source has a greater stimulating effect on satiety hormones or promotes better weight loss or composition changes compared to others.
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