Do protein shakes cause weight gain
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Do Protein Shakes Cause Weight Gain?
Protein Shakes and Weight Management
High-Protein Shakes and Weight Loss
Research indicates that protein shakes, particularly those high in protein and fiber, can aid in weight loss rather than cause weight gain. A study involving overweight and obese adults found that consuming a high-protein, fiber-based nutritional shake twice daily led to greater weight loss compared to a low-protein, lower-fiber placebo shake. Participants who consumed the high-protein shake lost an average of 3.3 kg over 12 weeks, while those on the placebo lost 1.8 kg . This suggests that protein shakes can be an effective tool for weight management when included as part of a calorie-restricted diet.
Soy vs. Casein Protein Shakes
Another study compared the effects of soy and casein protein shakes on weight loss in obese women. Both groups, consuming either soy or casein shakes as part of an energy-restricted diet, experienced significant weight loss. Over 16 weeks, participants lost an average of 12.7 kg, with no significant difference between the soy and casein groups . This indicates that the type of protein—whether plant-based like soy or animal-based like casein—does not significantly impact the effectiveness of protein shakes in promoting weight loss.
Plant-Based vs. Animal-Based Protein Shakes
A comparative study assessed the acute effects of whey, rice, and potato protein isolates on glycaemic regulation and appetite. The findings showed that plant-derived proteins (rice and potato) had a lower insulinaemic response and better glucose maintenance compared to whey protein. However, there was no significant difference in appetite perception among the different protein types . This suggests that plant-based protein shakes can be as effective as animal-based ones in managing appetite and supporting weight loss.
Conclusion
Overall, the evidence suggests that protein shakes, whether high in protein and fiber, soy-based, or plant-derived, do not cause weight gain. Instead, they can support weight loss and improve metabolic health when included as part of a calorie-restricted diet. The type of protein—whether from animal or plant sources—does not significantly alter the effectiveness of these shakes in promoting weight loss. Therefore, protein shakes can be a beneficial addition to a weight management regimen.
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