Lifespan News – Protein and Muscle

Emmett Short brings up a study talking about how diets with less protein are connected to better muscle maintenance with aging on this episode of Lifespan News.

Script

You want to know how to stay jacked into your 70s and 80s? Broscientists tell you it’s all about protein.

But a new study done by scientist scientists indicates less protein could help you maintain muscle mass as you age. But before you start slapping steaks out of grandpa’s mouth, you’re gonna want to hear the whole story.

Welcome to Lifespan News. I’m Emmett Short. Today, we’re talking protein and muscle mass. Now for the big controversy. Researchers publishing in Age and Ageing have found that, rather than being protective, an increase in dietary protein is associated with an increased chance of sarcopenia.

Sarcopenia is a well-known disorder that occurs with aging. People with sarcopenia lack adequate muscular function, leading to frailty, a higher risk of falls, and a functional decline in daily living activities that leads to a decreased quality of life.

Speaking of decreased quality of life, don’t go vegan just yet. Let’s break down some previous research and look at how this study was conducted.

Previous research has found the phenomenon of anabolic resistance, where muscle protein is more difficult to synthesize for older adults. This led the European Society for Clinical Nutrition and Metabolism to recommend that older adults consume 1 to 1.3 grams of protein per kg of desired body weight a day. Right in line with the Bro Scientists.

By the way, the European society for clinical nutrition and metabolism’s acronym is ESPEN? That makes no sense to me. Where did the P come from? Why is there no M? I like these guys because they’re telling me to eat protein but I’m not a fan of their acronym.

Anyway this new study used data from the TwinsUK cohort, a magical registry of almost 15,000 identical and fraternal twins and triplets, and the researchers narrowed in on about 3,300 older adults that had detailed muscular data.

As is usual for this kind of study, there was a lot of murky causal data. Aging is, of course, the primary association, but education, body mass index, and income were all also found to have associations with muscle strength, muscle mass, and sarcopenia. Yea, income and education so… take all this with a pretty big grain of salt.

There was no significant association between muscle strength and protein intake one way or another. Remember we’re talking about over 60 year olds here. But, protein intake below the ESPEN recommendation, so a low protein diet, was significantly correlated with more muscle and less cases of sarcopenia strangely. Add that to the data showing higher protein intake than ESPEN recommended was correlated with less muscle mass and more cases of sarcopenia and we have got ourselves quite a little mystery here.

The statistical relationship between protein intake, and Sarcopenia was even further confirmed when analyzed according to shared twin factors like genetics, early life history and a lot of other variables.

The researchers did speculate about causality. One idea was that the causality might be reversed: that people who suffer from sarcopenia might be eating more protein to try and treat their condition. The researchers thought this was unlikely, because sarcopenia is seldom diagnosed. But you know, you don’t need a doctor to tell you you’re getting thinner if you have a mirror. Just saying.

Another explanation could be that diets that are high in protein might also be high in inflammatory or other negative factors that promote sarcopenia, so it might be the type of protein that was causing the results instead of protein in general.

As suspect as these findings are, this study does throw doubt on the conventional wisdom surrounding protein and sarcopenia, and it might result in re-evaluations of dietary health guidelines. Could be a big deal. Now this is an association study that does not prove causation, but it makes it clear that simply eating more protein is not likely to protect anyone against developing sarcopenia. Exercise may be somewhat effective in fighting back against this disease, but more fundamental biological interventions are likely to be required, AKA pharmaceuticals, to actually prevent it for good.

So, what do you think? Will this study change how much protein you consume? Let us know in the comments. Make sure to subscribe and click the bell so you can stay up to date on aging research. I’m Emmett Short and we’ll see you next time on Lifespan News!