Whey protein made muscles grow faster, but it didn’t turn on the usual ‘growth switches’ in the cells—meaning it must be working through a different, unknown way.
Scientific Claim
In healthy older women, the muscle protein synthetic response to whey protein is not dependent on acute changes in mTOR pathway phosphorylation, suggesting alternative or downstream mechanisms drive its anabolic effect.
Original Statement
“There were no significant differences between supplemental groups in any target measured for changes in phosphorylation status (P > 0.05). Phosphorylation of p-4EBP1 Thr37/46 was significantly reduced from Baseline but not different from Rest in Exercise (P = 0.027), and phosphorylation of p-AKT Ser473 and p-mTOR Ser2448 were significantly reduced from Baseline in response to feeding but not different than Baseline with Exercise (P = 0.006 and P = 0.017, respectively).”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
The study directly measured signaling proteins and found no significant changes. The claim correctly interprets the absence of effect as evidence for alternative mechanisms, which is logically supported.
Evidence from Studies
Supporting (0)
Contradicting (1)
The study shows whey protein helps older women build muscle better than collagen, but it didn’t check the internal body signals (like mTOR) that might explain why—so we can’t say if the claim about those signals is right or wrong.