Do you really need more protein? It depends…
You need a lot of protein! Or so you’d assume, marvelling at the branding of candy bars, cereals, and, bizarrely, coffee and indeed water. Jorn Trommelen, Assistant Professor at Maastricht University’s School of Nutrition and Translational Research in Metabolism (NUTRIM) on who needs how much protein, and why.
After first fat, and then carbohydrates have had their stint as nutrient villains, protein has now emerged as the franchise hero. Every other highly-processed product in the supermarket is branded as containing protein. A vague sense that we need to consume as much of it as possible becomes at best pointless and, at worst, problematic when people think the healthy choice is a protein bar that is 25% protein and 26% sugar.
So how much protein do we actually need? Jorn Trommelen is a nutrition and exercise researcher, who dedicates himself to exactly that question. And his answer is disappointingly nuanced. “It’s all about context. Are you a professional athlete? Are you elderly? Are you in intensive care? I find it quite annoying when people trumpet numbers aimed at optimising muscle growth to a general population or when they dismiss the much higher protein needs of, for example, athletes.”
What is protein? And what does it do?
Protein is one of three macronutrients, alongside fats and carbohydrates. “The latter are mostly used for energy, whereas proteins are combinations of amino acids that we use to build and repair tissues.” Trommelen stresses that this doesn’t only apply to muscles. “It provides the building blocks for the brain, skin, internal organs, etc.: our lean body mass is mostly protein. Only between 10 and 15% of the protein you ingest ends up in the muscle — depending on how much you exercise.”
Protein, once consumed, is broken down into smaller building blocks. After the gut and liver have taken their share — around half — the rest is released into the blood stream, which transports the amino acids to all other tissues. “There’s always protein turnover, like a constant renovation: as the body repairs its tissues, proteins are being broken down and reassembled. We lose some protein in this process, but most of the amino acids from damaged proteins are recycled and used again to make new proteins. It doesn’t only come from the protein we eat.”
Muscles have high plasticity, that is to say they adapt to stimuli by growing, thus becoming stronger. “When you exercise, your muscles have an increased protein sensitivity for more than two days. The first dietary protein is integrated into the muscle within two hours of consumption already.” Trommelen is part of the M3 lab, which has shown this in experiments with state-of-the-art techniques. They produced a special protein and followed it throughout the body. Through muscle biopsies, they were able to determine how much of the ingested protein ended up in muscle tissue, and how this differed after rest or after exercise, for example.
“There’s no one answer to how much protein you need.”
Jorn Trommelen
Context-dependent guidelines
“That’s why there’s no one answer to how much protein you need. For those who don’t work out, 0.8 grams per kilo bodyweight per day is our best guess, based on studies where we measure people’s nitrogen balance. This is the minimum threshold at which 98% of all people won’t have a deficiency. Half of all people will even have a bit of a safety buffer with this recommended daily allowance.” For an 80kg individual, that would amount to 64 grams of protein. “Pretty much everyone in the Western world eats that and quite a bit more without trying, so I wouldn’t worry about that for healthy adults.”
While 0.8g/kg/day reliably prevents deficiencies, the number for optimal muscle growth in athletes is considerably higher. “The methodology to research that is different, but we see that more is better until it plateaus around 1.6 grams per kilo bodyweight.” That amounts to 128 grams for the same 80kg individual. Considerably more, however, 300 grams of chicken breast, a cup of Greek yoghurt and two eggs — while doubtlessly a sad meal — do cover that amount. There might be people who meet a pro athlete’s protein needs without trying.
“Obviously, it’s difficult to do experiments with professional athletes, because any change to their nutrition and training protocols can interfere with their progress, but we have studied how much Dutch athletes do eat in practice — and it’s 1.5 g/kg/day, so pretty much the ideal amount.” That figure applies to both strength and endurance athletes. While the former tend to prioritise protein, the latter eat a more balanced diet but consume more calories overall, so they end up with roughly the same amount of protein.
Plant-based vs animal protein
Many foods, also grains and legumes, contain protein. However, not all of them are equally usable for us. “Animal protein has the ideal mix of amino acids. That makes sense: a steak is a cow’s muscle; it has everything that your muscles need too,” explains Trommelen, while staying stumm on the pragmatic utility of cannibalism.
Plant protein has a less favourable mix of amino acids. Plant-based whole foods are also lower in protein and higher in fibre. The latter might interfere with the absorption of protein. “I think it’s great if my students go plant-based — be it because of animal rights or sustainability,” says Trommelen. However, he again warns about context: “They study sports science or nutrition, so they know what they’re doing: they know which protein sources to combine; they understand that, to be safe, they should eat a bit more protein, etc. However, if they recommend a plant-based diet to their parents, who maybe have less nutritional knowledge, don’t work out, and have higher protein needs because of their age, it can become problematic.”
Good, safe, not miraculous
So is it good to eat more protein? “More protein is conceptually a good idea, but the effect is vastly overstated, for example, when it comes to aesthetic outcomes.” Trommelen mentions that the protein craze is also fuelled by social media and dating apps, which have raised expectations when it comes to body composition, also for men. “If you’re working out a lot and looking for optimal hypertrophy, meeting the 1.6g/kg of protein recommendation and spreading it across 3-5 meals is the recommendation. But some athletes hope to maximize results by eating even more or setting an alarm clock in the middle of the night to wake up for another meal, which may do more harm than good.”
Trommelen adds that, apart from the obvious sustainability issues, there seem to be no negative consequences to eating more protein in healthy adults. Of course, a risk is that highly processed food marketed as “high in protein” may be mistaken as a health food. Therefore, he does not endorse slapping a protein label on every candy bar to profit from people’s vague desire for a nicer physique or overall health. “Protein shakes are a good supplement for athletes and bodybuilders. Still, the majority should come from healthy, whole food meals. In any case, don’t expect miracles…”
Text: Florian Raith
Photography: Jorn Trommelen
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