Unlock the Power of Protein: Debunking the "20-30g Myth" for Best Personal Trainer in New York
Unlock the Power of Protein: Debunking the "20-30g Myth" for Best Personal Trainer in New York
If you've been wondering how much protein you should be eating in a single meal, you're not alone. The "Best personal trainer in New York," "Fitness coach in NYC," and "New York City fitness trainer" are well-versed in the science of nutrition, including protein requirements. For years, popular magazine (and internet) folklore suggested that anything over 20-30g in a meal was a “waste.” That number was arbitrary. No science ever supported the idea that there was a useful within-meal limit for protein intake.
However, a few years back, two particular studies were designed to answer this very question. Well, sort of.
What Does the Research Say?
The first study showed that when college-aged weight-trainers drink 0g, 5g, 10g, 20g, or 40g of protein after a weight training session, muscle protein synthesis is stimulated maximally at the 20g dose. Interestingly, there were no further increases in muscle protein synthesis at the 40g dose.
The second study showed that when young and elderly volunteers were given 30 or 90g of dietary protein in a single meal, the 30g dose maximally stimulated muscle protein synthesis. Again, there were no further increases in muscle protein synthesis at the 90g dose.
Case Closed? Or Is It?
Oddly, since the publication of those two studies, most fitness pros have closed the book on this topic of per meal protein needs. Articles have been written, minds have been made up. Indeed, some authors have even suggested that we’re ignorant wastrels if we dare eat more than 20-30g of protein in a single sitting.
But wait just a second. What did those two studies actually show?
They showed that at 20-30g in a single meal, protein synthesis is maximally stimulated. Which raises an important question: Is muscle protein synthesis the only reason we eat protein? Actually, no.
Protein Synthesis and Breakdown
In a more recent review, Dr. Robert Wolfe, one of the top protein researchers in the world, argues that, while the muscle protein synthesis information above is interesting, it’s essentially useless when planning lunch.
You see, 20-30g of protein at a single meal does max out protein synthesis. The studies are clear on that one. However, what this information misses is that protein anabolism is a function of protein synthesis and breakdown. And, according to the research, protein breakdown is slowed with ever-increasing amounts of protein in a single meal. In other words, “there doesn’t appear to be a practical upper limit to the anabolic response to protein in a single meal.” (Quoted from Dr. Wolfe).
So, if you eat a big protein meal, that extra protein isn't "wasted." Instead, it creates a scalable anabolic response in proportion to the intake. It does this by suppressing protein breakdown. By extension, whether you eat small protein meals spread throughout the day, or you eat just a few big protein meals a day, assuming intake is the same, you may benefit from the same anabolic response.
And yes, this claim is backed up by research too.
Check out this study for more. In it, when 80% of the daily protein intake was eaten in a single meal – as much as 100g of protein eaten at once - it was more anabolic than spreading the same amount of protein throughout the day. In essence, large, infrequent protein meals were more anabolic in this study vs. small, frequent protein meals. Of course, as with all research, the data are mixed. Some studies show this effect. Others do not. However, the take-home message is the same: if you actually look at the full body of research, it becomes clear that there’s not really a practical upper limit of protein intake for optimizing muscle protein. So much for the 20-30g myth.
Remember, Muscle Isn’t Everything
Beyond this very narrow view of protein intake (muscle protein synthesis vs. breakdown), there’s a much more important question at stake: why else do we eat protein?
You see, there are other benefits to eating protein beyond muscle building. There’s satiety, the thermogenic effects, the impact on the immune system, and more (see below). Plus, there are probably a few benefits science can’t measure yet. I say the last part because there’s so much experiential evidence suggesting that when you’re training hard and you up your protein intake, you do better. So maybe we just haven’t looked in the right places to notice the real benefits.
Other Protein Benefits
We shouldn’t look at the world through a straw (i.e. see one protein study on one isolated topic and make broad generalizations). So, to help us remember that, let’s review a list of benefits we get from eating extra protein.
Increased thermic effect of feeding – While all macronutrients require metabolic processing for digestion, absorption, and storage or oxidation, the thermic effect of protein is roughly double that of carbohydrates and fat. Therefore, eating protein is actually thermogenic and can lead to a higher metabolic rate. This means greater fat loss when dieting and less fat gain during overfeeding/muscle building.
Increased glucagon – Protein consumption increases plasma concentrations of the hormone glucagon. Glucagon is responsible for antagonizing the effects of insulin in adipose tissue, leading to greater fat mobilization. In addition, glucagon also decreases the amounts and activities of the enzymes responsible for making and storing fat in adipose and liver cells. Again, this leads to greater fat loss during dieting and less fat gain during overfeeding.
Metabolic pathway adjustment –When a higher protein (20-50% of intake) is followed, a host of metabolic adjustments occur. These include: a down-regulation of glycolysis, a reduction in fatty acid synthesis enzymes, and an increase in gluconeogenesis - a carbohydrate “draining” effect where carbons necessary for ridding the body of amino nitrogen is drawn from glucose.
Increased IGF-1 – Protein and amino-acid supplementation has been shown to increase the IGF-1 response to both exercise and feeding. Since IGF-1 is an anabolic hormone that’s related to muscle growth, another advantage associated with consuming more protein is more muscle growth when overfeeding and/or muscle sparing when dieting.
Reduction in cardiovascular risk – Several studies have shown that increasing the percentage of protein in the diet (from 11% to 23%) while decreasing the percentage of carbohydrate (from 63% to 48%) lowers LDL cholesterol and triglyceride concentrations with concomitant increases in HDL cholesterol concentrations.
Improved weight loss profile – Research by Layman and colleagues has demonstrated that reducing the carbohydrate ratio from 3.5 – 1 to 1.4 – 1
