Even though whey protein made muscles build faster, it didn’t change the usual ‘on/off’ switches in muscle cells that are supposed to control growth—suggesting other mechanisms are at play.

Scientific Claim

In healthy older women, neither whey nor collagen protein supplementation significantly alters phosphorylation of key anabolic signaling proteins (e.g., mTOR, AKT, S6) 4 hours after ingestion, with or without resistance exercise.

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).”

From study:Whey protein but not collagen peptides stimulate acute and longer-term muscle protein synthesis with and without resistance exercise in healthy older women: a randomized controlled trial.

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 used validated Western blot methods with proper controls and normalization. The absence of significant differences (P > 0.05) across groups is a definitive negative result supported by the design.

Evidence from Studies

Supporting (0)

No supporting evidence found

Contradicting (1)

Whey protein but not collagen peptides stimulate acute and longer-term muscle protein synthesis with and without resistance exercise in healthy older women: a randomized controlled trial.

Randomized Controlled Trial

Human

2020 Mar 1

This study didn’t check the specific muscle signals mentioned in the claim, but it did find that whey protein helps older women build more muscle than collagen, with or without exercise — so the claim might be missing something important.

Source Study

Whey protein but not collagen peptides stimulate acute and longer-term muscle protein synthesis with and without resistance exercise in healthy older women: a randomized controlled trial.

Score: 66

DOI: 10.1093/ajcn/nqz332

Similar Assertions

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.

84%

After drinking whey protein shakes every day for a week, older women’s muscles kept building up new protein even on days they didn’t exercise—collagen protein didn’t do this at all.

83%

Even with daily exercise, collagen protein shakes didn’t help older women’s muscles build new protein over a week—whey did, but collagen didn’t.

80%

When one leg got whey protein and exercise, the other leg (which didn’t exercise) still showed similar muscle-building activity—meaning the effect was happening all over the body, not just where the exercise happened.

79%

Doing leg exercises helps whey protein build muscle even more—but even with exercise, collagen protein still can’t match whey’s muscle-building power.

79%