Some of you have asked me about the sarcopenia study making the rounds. It comes to a startling conclusion: that the more protein you eat, the greater your risk of sarcopenia, or muscle wasting.

First of all, if you don't want to read any more, rest assured that this is absolute nonsense. The conclusion isn't justified by the study in question and the conclusion is also contradicted by actual controlled trials looking at this exact question. 

What was the study?

Out of 3,302 older adults (twins) living in rest homes, they found the ones who had sarcopenia—129 people—and looked at their protein intakes. 45 of the sarcopenia people had high protein intakes. 19 of the sarcopenia people had low protein intakes.

By "looked at their protein intakes," they consulted food frequency questionnaires they'd filled out across the last few decades. By the way, the time points of these measurements are very unclear. The twin data collection is described here. Twins were enrolled in 1992-2004. Follow-up data was collected in 2004-07, then 2007-12, then 2012-18. But we don't know when in this time range the FFQs or the dexa scans (to determine sarcopenia) were administered to the people in this study. There is also significant missing data (supp table 5 in the main paper here says 21% missing protein data). Some twins in the database also have multiple FFQs, but we don't know how any of these were handled.

So right there, it's all very unreliable.

Second, this was an observational study that cannot establish cause and effect. It could even be reverse causality—the people with sarcopenia were more likely to eat high protein because they were trying to overcome the sarcopenia. Maybe their doctors were even prescribing high-protein diets. We simply don't know.

Third, the bias of the authors is evident in the discussion section, where they target "animal protein" and focus on how "red meat" must also "be considered" in the context of "the global climate crisis." This is not just about the facts of the study. It's about "red meat as a scourge, a blight on us all."

Fourth, we have controlled trials that look at this question and answer it. If you have sarcopenia, eating more protein can overcome this. Especially if you lift weights while eating more protein. Let's look at a few:

• In older cancer patients, adding whey protein isolate (scary animal protein) improves body composition, increases muscle mass and strength, and improves resistance to chemotherapy toxicity.
• In older women, resistance training with whey protein isolate increases strength, muscle size, and functional capacity.
• In older adults with sarcopenia, adding protein via whey improves muscle retention and reduces the progression of muscle wasting.
• In another group of adults with sarcopenia, adding protein via leucine-enhanced whey (so a higher protein protein supplement) improved lower body muscle mass and functional capacity.

#listentothesisson