By Angus Dalton
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Sick of having arms with the muscle definition of an udon noodle, I have become obsessed with protein.
TikTok fitness influencers bade me to concoct a slurry of strawberry (protein-enriched!) yoghurt mixed with a scoop of protein powder after hitting the gym.
This is my life now.
That produced a filling sludge with 45 grams of protein and all the appeal of the pink goo favoured by Teletubbies.
I have consumed horrible amounts of chicken breast and choked on arid protein bars, all in pursuit of an astronomical protein goal of 180 grams of protein per day.
But taking a look at the fascinating science of protein – perhaps the key nutrient behind weight loss, muscle gain and living longer – I came to realise I shouldn’t be emulating TikTok coaches (shock horror).
I found a new diet guru in Stella, a baboon. Here’s what she taught me.
How protein can cure a locust’s voracious hunger
In 2010, an anthropology student stalked Stella for 30 days on the outskirts of Cape Town in South Africa and tracked everything the wild Cape baboon ate.
Stella devoured dandelion leaves, blood orange peel, pine nuts, acorns, grasses and an array of herbs. By analysing the detailed data of her meals, researchers discovered Stella’s nutrition was perfect. She nailed the right ratio of protein to fats and carbs for a female of her size almost every day.
Longtime colleagues Professors Stephen Simpson and David Raubenheimer, now at the University of Sydney and authors of Eat Like the Animals, built on this observation. They put hundreds of locusts in boxes with a food source that was either low-protein and high-carb, or high-protein and low-carb.
Locusts: voracious eaters! (Unless they get enough protein.)Credit: AP
The low-protein group overate voraciously. They hit adulthood later and grew fat. The high-protein locusts stopped eating too soon and grew dangerously lean because they consumed too few carbs.
Given the choice of eating whatever they liked, locusts had perfect nutrition, just like Stella. The same instinctive dietary accuracy has been observed in cats, dogs, cockroaches, beetles, and even slime moulds.
So why do humans struggle?
The reason chips are irresistible
Simpson tells me every organism has different appetites for different things and, sometimes, one of those appetites dominates the others. It is evolution’s way of ensuring animals seek out the nutrition they need.
In predators such as cats, dogs, spiders, killer beetles and carnivorous fish, their strongest appetite is for fat. They get plenty of protein from prey, but fat is rarer, so it rules their hunger.
Humans, meanwhile, have five appetites: one each for protein, carbs, fats, sodium and calcium. But for primates, including us, the appetite for protein is the most powerful of all.
Weirdly, though, protein intake on a population level hasn’t increased in step with obesity, while consumption of fats and carbs has skyrocketed. That’s why the latter nutrients have been the focus of diet fads for decades.
Stella, the nutritionally perfect baboon: no diet books, no problem.Credit: Marija Ercegovac
But here’s Simpson and Raubenheimer’s bold idea: it’s our ravenous appetite for protein that is driving that overconsumption. This is called the protein leverage hypothesis.
Modern processed food dilutes protein with so much fat and carbs that we have to eat more calories in total to satisfy our protein appetite and feel full, the idea goes.
When we haven’t eaten enough protein, the liver secretes a hormone called FGF21, which makes us crave savoury flavours, for example.
“In our evolutionary past, savouriness, umami, was linked to amino acids and protein in food. So when you need protein, your body says, ‘look for savoury flavoured things’,” Simpson says.
But often the most readily available savoury hit is a processed snack like chips or instant noodles. They pack the umami flavour of protein without the satisfying payoff. They are “protein decoys”.
The umami hit: savory snacks such as chips trick the body into thinking it’s getting protein with none of the satisfying payoff.Credit: Getty Images/iStockphoto
In this world of ultra-processed foods, we are like the locusts in the low-protein box, driven to overeat.
“We’ve looked at probably 50 species of animals over the years. They all have this inherent nutritional wisdom, and we do too. That’s the good news. Our appetites aren’t broken. They still work,” Simpson says.
“It’s just that we put them in the wrong environment.”
How much protein should you eat?
So what should we do with this knowledge? Says Simpson: “Listen to your protein appetite. Avoid savoury flavoured snack foods. Seek out high-quality protein foods.”
By being mindful that your appetite is driven by protein, and prioritising high-protein wholefoods alongside a high fibre intake, you’re almost automatically less likely to overeat.
Good sources of protein
- Lean meats such as chicken breast, lamb fillet, white fish, pork fillet or beef fillet, skin and excess fat removed, (100g cooked = 20-40g protein)
- Fresh or canned salmon and tuna (100g cooked = 25g protein)
- Eggs (110g = 12g protein)
- Greek yoghurt (1 cup = 20g protein)
- Cottage cheese (110g =12g protein)
- Beans, lentils and chickpeas (200g cooked = 20g protein)
- Tofu and tempeh (100g = 10g protein)
- Quinoa (185g = 8g protein)
- Nuts and seeds (35g = 7g protein)
“You can be more like Stella the baboon, rather than worrying about counting calories on your apps,” Simpson says.
The recommended protein intake varies with age and medical factors. But here’s how to get a rough guide.
Use an online calculator to deduce your daily calorie requirement. Times that number by the proportion of protein you need per day: about 0.15 (i.e. 15 per cent). More specifically, you can use 0.18 for 18–30-year-olds; 0.17 for people in their 30s and up; and 0.20 for people older than 65.
Nutrition researcher Professor Stephen Simpson is academic director of the Charles Perkins Centre at the University of Sydney and executive director of Obesity Australia.Credit: Louie Douvis
Divide the result by 4 to get an estimate of your protein requirement in grams. When I did this calculation, my requirement came out at 120 grams, far below the goal I was shooting for.
And here’s the intriguing thing: looking back through my diet tracking, that’s exactly the amount of protein I hit each day before feeling completely full. Eating anything more was a battle.
I had been satisfying my protein appetite perfectly without knowing – just like Stella.
And there’s developing research to show that it may be worth keeping my intake there. Too much protein supercharges ageing and cuts lifespan partly through the build-up of cellular protein waste. Simpson is a little horrified when I tell him about my 180-gram goal.
“Oh, god,” he says. “If you force the extra protein down, you’re super-charging all the deleterious effects of excess protein intake. And most of it’s being peed out.
“If more is good, even more isn’t better. Nutrition is all about balance. There are costs to eating too much or too little of anything, particularly protein.”
My takeaway? I’m ditching the pink sludge. Thanks, Stella.
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