Protein Syntheses, Thermogenesis, and Metabolism
How much protein can you eat in each meal? As much as you want. You’ll only get leaner. Here’s why.
The fitness world is haunted, not by ghosts but by bad and outdated ideas. And no matter how educated we become, we hear them rattling their ethereal chains.
Here’s an example: A while back, I wrote about increasing your calories just enough to support optimal muscle gains without adding too much body fat. I suggested a simple daily 500-calorie shake. I ran the macros and saw that the shake contained about 53 grams of protein. That’s when my internal EMF meter went off:
“But wait, can I absorb that much protein in one sitting? Won’t excess protein turn to fat? Will I get pudgy and lose my OnlyFans subscribers?”
I knew this was just a bad-idea ghost, but I had to reassure myself. I dove into the research and found a few things that helped purge the poltergeist.
Protein Syntheses vs. Thermogenesis
You’ve heard for years that most lifters need roughly 25-40 grams of protein per sitting, depending on their body weights, to optimize muscle protein synthesis, the process of growing new muscle tissue. That’s true, but this discovery summoned a lot of ghosts.
Based on these protein synthesis studies, some well-meaning experts chose a number in the middle, like 32. All you need is 32 grams of protein per meal. Any more than that does nothing. Or worse, the excess protein gets “converted” into body fat. So 32 grams became “the rule.”
For bodybuilders or athletes trying to consume about a gram of protein per pound of body weight, that meant eating six meals per day. That, too, became “the rule.” Then we all started lugging around Tupperware containers of tuna and setting alarms to eat every three hours. Good times.
The problem? Mainly, this: the 32 grams per meal rule was based solely on muscle protein synthesis. Yes, there is a ceiling. Past a certain point, extra protein won’t boost MPS much. But (and this is a big hip-thrust-built but) it also won’t turn into body fat. In fact, the opposite is true. That extra protein actually makes you leaner by increasing thermogenesis.
The Study
Researchers had a bunch of overweight men and women consume either 30 or 50 grams of protein. After, they measured their metabolic rates for over five hours. Energy expenditure was measured by indirect calorimetry. They also collected blood, breath, and urine samples to measure substrate oxidation and other metabolic parameters.
What happened? The group who consumed 50 grams of protein experienced a sweet boost in metabolic rate. The thermic effect was 34% higher than that of the group eating just 30 grams of protein.
Smart-guy types call this diet-induced thermogenesis, and it’s related to TEF or the thermic effect of food. As you know, protein has a much higher TEF than carbs or fats. Digesting and assimilating protein generates lots of heat and burns up lots of energy/calories – thermogenesis in a nutshell.
In a related study of weight-lifting men and women ingesting 800 extra daily calories from protein, not a single lifter gained fat, even after 8 weeks. Diet-induced thermogenesis certainly played a role there.
What Does This Mean to You?
It means you can forget the old rules. Bill Campbell, Ph.D. summed it up like this:
“This finding is really neat because it lets us know there’s not a threshold (or ceiling effect) for the amount of protein you can ingest in one meal and its ability to increase your metabolic rate response.”
I like to think about it like this: The first 25-40 grams of protein in a meal helps me build muscle; anything over that helps me stay lean.
A little simplified? Yes. But the ghosts have been exorcised. This house is clean.
This also fully supports the protein-first eating strategy. Revolve your nutrition around protein, eat about a gram of protein per pound of body weight, and the rest of your diet pretty much autoregulates and falls into line with your goals: more muscle, less fat.
My approach is to have two MD Protein (on Amazon) shakes per day, either between meals or as meal replacements. Each shake contains 42 grams of protein or more if I add extra goodies. And now I know that I don’t need to worry about those “excess” grams in each shake. They just help keep the body fat off. They’re also delicious.
