Nature weighs in on the protein question

Quite a good article to be found here at Nature about the fitness influencer craze for recommending super high protein intake.  Some bits:

“It’s really frustrating because there isn’t evidence to support the claims that they’re making,” says Katherine Black, an exercise nutritionist at the University of Otago in Dunedin, New Zealand, referring to the super-high protein recommendations often shared on social media. What research does show is that protein needs can vary from person to person and can change throughout a lifetime. And people should think carefully about what they eat to meet those needs. “On social media, it’s like everyone’s worried about protein, putting protein powder into everything,” she says.....

This part, explaining how they even work out protein needs, is interesting:

Researchers have been trying to estimate how much protein people need for more than a century. In 1840, chemist Justus von Liebig estimated that the average adult required 120 grams of protein a day, on the basis of a group of German workers’ diets. Later, scientists started to use nitrogen to calculate protein requirements. Protein is the only major dietary component that contains nitrogen. So, by measuring how much of it people consume and the amount they excrete, researchers could estimate how much the body uses.

Since the 1940s, this nitrogen-balance method has been used to determine the Recommended Dietary Allowances (RDA), a set of nutrient recommendations developed by the US National Academies of Sciences, Engineering, and Medicine.

The latest such recommendation for protein, from 2005, establishes the RDA for both men and women at 0.8 grams per kilogram of body weight per day, which it states should be enough to meet the needs of 97–98% of healthy people. European and global-health authorities recommend similar or slightly higher levels.

Although scientists recognize that RDAs are a useful reference point, many say that people could benefit from a higher amount. “The RDA is not a target; it’s simply the minimum that appears to prevent any detectable deficiency,” says Donald Layman, a researcher focusing on protein requirements at the University of Illinois Urbana–Champaign. Evidence suggests1 that the optimal range is between 1.2 and 1.6 grams of protein per kilogram of body weight per day, he says.

That is especially true for older adults, who often experience muscle loss as they age, as well as for certain athletes and people trying to gain muscle.

For example, in an observational study of 2,066 adults aged 70–79, those who reported eating the most protein — about 1.1 gram per kilogram of bodyweight — lost 40% less lean mass during the three years of follow-up than did those who ate the least — around 0.7 grams per kilogram2.

“For older adults, 1.2 grams per kilogram is just giving them a little extra protection,” says Nicholas Burd, a nutrition and exercise researcher also at the University of Illinois Urbana–Champaign. Furthermore, older people might experience a decline in appetite, which makes it particularly important for them to pay attention to their protein intake. It doesn’t mean that they need to take protein supplements, he says. “It’s all things we can do with just normal incorporation of high-protein foods in our lives.” 

 Actually, a couple of Youtube people I have watched on the topic have suggested that 1.2 grams per kg a day, especially for older, so this gives me confidence I am not watching nutters.