What Happens When You Eat More Protein?
A Deep Dive Into Muscle, Metabolism, and the Bigger Picture
Reflecting on Eight Weeks of Research
These past eight weeks highlight the most time I’ve ever spent reading research. Unsurprisingly, I’ve learned a great deal—and even less of a surprise, I’ve realized how little I actually know.
That’s OK with me. I’m happy to open doors, even if they sometimes lead to more doors. We all have a certain number of thresholds we’re willing to cross before deciding, “that’s plenty.”
Still, I’m not satisfied with how much I know about protein: how it’s metabolized, which tissues need it most, and what effects consuming various amounts has on our physiology.
The Boring Version vs. The Fun Version
That’s the boring version.
The fun version is: “If I eat more protein, does it help me get more jacked and lean?”
It certainly isn’t going to help my tan—but that’s cool.
Debunking the Muscle Myth
It’s quite common to think:
Training = Muscle damage → Protein = Muscle repair = Bigger muscles
That’s reductive, but it’s what I’ve believed for a long time.
The problem is, muscle tissue accounts for less than half of our lean body mass—so it isn’t the main draw on the protein we eat. All of our organs (skin, heart, brain, liver, kidneys, gut) are highly metabolically active and turn over protein at higher rates than muscle.
In fact:
If you compare the amount of calories burned per kilogram of weight, muscle tissue ranks lower than all other organs.
If you compare the percentage of amino acid (protein) utilization by organ, muscle comes last again.
Understanding the “Amino Acid Pool”
Professor Don Layman has noted that we typically turn over about 300g of protein per day. Naturally, this doesn’t all come from our diet—most people don’t eat that much (I’m close, though).
The amino acids we use for building and repairing tissue come from:
The protein we eat
The protein broken down from our own organs
This all enters the intracellular matrix and bloodstream to form what’s known as the “amino acid pool.” Think of this as a circulating supply of amino acids, constantly fed by diet and organ turnover, that all organs (muscle included) draw from for repair and growth.
Can We Store Protein?
Naturally, if you consume more protein, there’s more available for all of the body’s processes.
But unlike carbohydrates or fat, we don’t really store protein.
The gut pulls about half of the amino acids in one meal for later use
Aside from that, we don’t “stock” extra protein the way we do fat or glycogen
You’re probably thinking:
“If we eat what we need, and we can’t store more, then what’s the point?”
Since we cannot store protein, most of the surplus is oxidized (burned for energy) or converted into other usable substrates like glucose or ketones.
So… Is All This Extra Protein I’m Eating Doing Anything?
Does eating extra protein—like all the steak I’m crushing—actually benefit me?
C’mon man!
More Protein Isn’t Always Better—But Can It Help?
It’s long been wishful thinking that simply eating more protein leads to better performance, faster recovery, and more muscle in a linear fashion.
Charles Poliquin promoted eating 2g per pound of bodyweight to break through training plateaus
Arnold’s Encyclopedia emphasized protein (especially red meat and eggs) over carbohydrates for muscle growth
Naturally, every new trainee who starts lifting often sees rapid muscle gains, typically alongside a sharp increase in protein intake—driven by magazines, gym culture, and the internet.
But beyond meeting new protein turnover needs...
Is all that extra protein really worth it?
Does consuming more than what’s necessary for increased muscle protein synthesis (MPS) actually improve results?
It helps to expand our focus beyond bigger biceps—factors like faster recovery, reduced soreness, better blood sugar control, decreased hunger, and enhanced anabolic drive also play a major role in effective nutrition strategies.
What Do We Actually Use Protein For?
This part, in my opinion, is where most people interested in protein get tripped up.
Until the past couple of years, I didn’t fully realize how much more protein is needed beyond just growing muscle.
Some key principles that shifted my perspective:
Up to 50% of ingested protein is stored in the gut (along with most ingested glutamine). This storage acts as a buffer between meals.
The remaining amino acids head to the liver for synthesis and oxidation—up to 75% of them are metabolized there, with only a small portion (mostly BCAAs) reaching muscle tissue.
Amino acids are also used for hormones, energy production, substrate synthesis, and whole-body protein turnover.
What Happens If We Eat More Than We Need?
The RDA for protein is 0.8g/kg
The ISSN position stand recommends 1.4–2.0 g/kg for active individuals
Dr. Jose Antonio recommends 1.8 g/kg minimum for weight-training individuals (Antonio et al., May 2014)
In an article by Schoenfeld and Aragon (JISSN, Feb 2018), they reference research from Stu Phillips’ lab showing that MPS is maximized with 20–25g of protein per meal.
But there’s nuance here.
Many of these studies use whey protein alone, which raises questions about applicability to whole food diets.
Wolfe et al. (2015) gave subjects either 40g or 70g of protein from beef:
40g led to maxed-out muscle protein synthesis
70g led to increased total body protein synthesis
Measuring only MPS ignores all the other protein-demanding tissues. There’s more going on than just muscle growth.
Digestion, Oxidation, and Utilization
Whey and hydrolysates can bypass slow digestion, leading to a sharp spike in blood amino acids—but also increased oxidation in the liver.
Higher protein intakes result in:
Increased protein storage (in the gut)
Greater oxidation in the liver
More protein breakdown at night
Even direct infusion of amino acids into the bloodstream mostly results in uptake by the intestines and liver, not muscle.
Wahren et al. (1976) studied diabetic patients given 3g/kg of protein:
BCAA levels doubled
Blood amino acid levels rose only 30%
The majority was used before ever reaching the bloodstream.
So... Is Extra Protein a Waste?
It felt that way at first. More amino acids = more oxidation = diminishing returns.
But there’s another side to it.
The idea that increased oxidation contributes to the body's anabolic drive, combined with positive body composition changes, gives reason to reconsider.
Antonio et al. (2015) showed that:
A high-protein diet (3.4g/kg) led to reduced body fat and increased lean mass
At 150 lbs (68kg), that’s 231g of protein/day
Despite eating more calories, subjects improved their body composition
Yes, this study used client-reported data, so it isn’t bulletproof—but the findings are compelling.
Even if extra protein simply results in spontaneous calorie restriction, it still leads to positive body comp changes.
So... What Does This Mean For Me?
Whether the improved body comp came from the thermic effect of feeding (TEF) or subconscious calorie reduction may not matter from a practical standpoint.
At the end of the day, positive changes with minimal risk are what most clients and coaches care about.
Personally, I’m still diving into this.
But I suspect that:
Higher protein intake burns more calories through digestion
This helps with fat loss, either by letting you eat more without gaining fat or cutting faster with the same calories
Protein’s satiety factor means less hunger on a deficit
And when bulking, more protein may lead to less fat gain, thanks to its appetite-regulating effect
Overfeeding: A Closer Look
Webb and Annis (1983) overfed subjects 1,000 calories per day and tracked predicted vs. actual fat gain:
Predicted fat gain:
5 kg of fat (based on 6 kcal/g)
Actual fat gained:
Mixed American Diet: 2.68 kg (46% less) with a 7% increase in adaptive thermogenesis
High Protein Diet: 1.75 kg (65% less) with a 14% increase in adaptive thermogenesis
Even the lower-protein group adapted. Despite 1,000 extra calories/day, they didn’t gain as much fat as expected—and the high-protein group gained even less.
In Jose Antonio’s 2017 narrative review, every study on high-protein overfeeding showed a protective effect.
The Practical Takeaway for Clients
From both a metabolic and behavioral angle:
More protein = improved fat loss
More protein = reduced fat gain while bulking
More protein = better satiety = subconscious calorie control
Now, if someone is trying to aggressively bulk, eating tons of extra protein might just make them too full. But for the rest of us, there’s a strong argument for eating above the JISSN’s 1.4–2.0g/kg range.
Final Word
Consuming protein above your daily needs probably won’t boost muscle growth beyond its ceiling, but it does ensure you're:
Maximizing muscle repair
Supporting full-body protein turnover
Making calorie restriction for fat loss easier
Possibly reducing fat gain when overeating
A practical win across the board.
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