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Rebalancing Amino Acids

By Christopher Walker

The importance of protein has finally started to be recognized by the majority of health and fitness professionals.

Of course, this is something that bodybuilders and athletes have known for a while and even taken to the extreme with the amounts they consume.

However, most of what is talked about is the importance of protein for muscle growth and fat loss, not necessarily overall health and metabolism.

Table Of Contents

One thing that is often discussed is the “Thermic Effect of Protein”, which is not the same as the increase in cellular metabolism that we have talked about in other posts. This represents your digestive system needing to work harder to break the protein down into its amino acids in order to be absorbed, rather than an actual increase in the way your cells produce energy.

Now, unlike sugar and fatty acids, protein acts more on the hormonal and regulatory level than it does on the cellular level, which makes sense - protein cannot be directly burned for fuel, it must first be converted into either glucose or fatty acids.

The important aspects of protein for metabolism and health comes down to quantity - getting the right amount - and quality - rebalancing the amino acids.

Before we get to that though, we need to lay the groundwork about protein.

Read More: The Metabolism Spectrum (Do You Have A Low Metabolism?)

The Basics Of Protein:

the basics of protein

All protein, no matter the source, consists of many amino acids combined together.

Whenever you eat protein, your digestive system breaks these proteins down into the individual amino acids to be absorbed.

These amino acids then enter the bloodstream, where they are used throughout the body for a huge variety of things, like building tissues, synthesizing hormones, creating enzymes, and sometimes getting broken down into fuel.

There are 20 total amino acids in your body, and they each have different uses and effects. Certain ones can be transformed into other ones as the body needs them.

However, there are specifically 9 amino acids that the body cannot make, that need to be supplied by the diet. These are called the “essential” amino acids for this reason, and they are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

The other amino acids can either be “conditionally essential”, meaning that we often need more of them than our body can make, or “non-essential”, meaning that we generally make enough of them to avoid deficiency symptoms.

The conditionally essential amino acids are arginine, cysteine, glycine, glutamine, proline, and tyrosine.

The non-essential amino acids are alanine, aspartic acid, asparagine, glutamic acid, and serine.

Now, these amino acids all have different effects in the body based on the proportion that you are eating them in, and if certain ones are emphasized over others, you can put your internal environment in a state of stress.

The Anti-Metabolic Amino Acids:

anti-metabolic amino acids

Certain amino acids cause inflammation in the body and encourage or activate stress responses and stress hormones.

The main ones are cysteine, methionine, and tryptophan, which you’ll notice are all in the “essential” category. That is, while we need a certain amount of these amino acids for specific functions in the body, too many of them out of balance will put our bodies in an increased state of stress, mimicking our physiology during a famine.

Why is this happening?

To answer that question, we need to look at what happens in the prolonged stress, “famine” physiology.

As we have talked about in other posts, during times of starvation, the stress metabolism takes over to limit our energy production and increase fat storage in order to maximize our survival.

Since glucose is not coming into our bodies from food, your body must make its own glucose from amino acids in order to keep blood glucose from dropping too low, in which case we would die.

To do this, we release cortisol, which breaks down protein in our tissues, notably muscle tissue, into glucose for the blood.

What is important in our discussion of metabolism is the higher ratio of the specific amino acids that are broken down from the muscle tissue - cysteine, methionine and tryptophan.

That is right: In times of famine, your blood gets flooded with these amino acids, which means that food is scarce. Your body responds with an increased stress response and inflammation, lowering your metabolic rate, thyroid production, and long-term health.

Tryptophan is probably the most noteworthy because of its conversion to serotonin in the brain.

Serotonin, despite being claimed as the happy hormone (spoiler: it is not), is more associated with stress, reduced metabolism, hibernation, and physical/mental fatigue than anything else. It is also connected strongly to the hormones prolactin, estrogen, and cortisol (all causing each other to rise).

Remember our discussion of the different energy pathways? Serotonin stimulates the stressed, glycolytic pathway of energy production, leading over time to less oxidative phosphorylation and a lower metabolism. This is furthered by the fact that serotonin decreases thyroid.

Now, as we talked about before, these amino acids are essential, meaning that your body cannot make them on their own, and you need to eat a certain amount of them.

The fact that they are anti-metabolic does not mean that you should not eat them, simply that you need to balance them out with a higher proportion of the other amino acids, specifically the anti-inflammatory, pro-metabolic amino acids.

The Pro-Metabolic Amino Acids:

pro-metabolic amino acids

Opposing the anti-metabolic amino acids, we have the pro-metabolic amino acids that shut down stress and signal to our body that food is abundant.

To explain why these are pro-metabolic, we need to imagine what life would look like in times of abundance and where we would get our protein from.

Our main source of protein would be animals.

In times of famine, we would not eat many animals, but would instead use our own muscle proteins, more specifically, the anti-metabolic ones.

But in times of abundance, we would get our protein from animals, and not just their muscle meat, but from the whole animals - collagen, organs, tendons, ligaments, and all.

This point is incredibly important because an animal’s muscle meat is very similar to our muscle meat; it is composed of a higher proportion of the anti-metabolic amino acids.

However, their collagen, organs, ligaments, and tendons all have a very different amino acid composition. Primarily, they are very high in the pro-metabolic amino acids, glycine, proline, and alanine. These amino acids do not decrease thyroid production like the anti-metabolic amino acids do.

Glycine, specifically (which balances and help removes excess of the anti-metabolic, methionine) has shown to reduce inflammation, reduce stress and cortisol levels, protect against endotoxin, reduce blood pressure, protect the liver, protect against the effects of alcohol, improve immune function, reduce inflammation, protect against muscle and bone loss, improve sleep and reduce fatigue, improve oxidative status, and protect cells.

It is also associated with a better lipid profile, less obesity, less hypertension, less insulin resistance, and less heart attacks, as well as plays an important role in metabolism, antioxidant status, and brain health.

But probably most importantly, glycine has been shown to protect thyroid production and blood flow of glucose and oxygen to tissue cells.

For a convenient way to get your glycine rich protein make sure to check out UMZU's zuCollagen protein!

zucollagen by umzu

And while most of research is focused around the benefits of glycine (which seems to be the MVP of the pro-metabolic amino acids), the others have similar benefits.

Now you might be wondering, can our bodies not make this amino acid? And if that is true, it is not one of the “essential” amino acids.

However, our production falls short of our needs, leading many to believe it should be considered “semi-essential”.

By eating more of these amino acids from organ meats, bone broth, and gelatin/collagen, you can shift your internal environment towards the healthy, oxidative metabolism, while reducing inflammation and stress.

This, of course, has HUGE implications for our diet in the modern world.

Modern Protein Diets

modern Protein Diets

In traditional cultures, protein sources typically would be closer to the “whole animal” that we would have eaten in nature.

Things like chicken foot soup, oxtail, bone broth, and gelatin/collagen all contain a high proportion of the pro-metabolic amino acids.

However, in modern culture, we typically only eat muscle meat from animals. When you think of “chicken”, “turkey”, “beef”, or “pork”, these are all the muscle meats of the animals.

So by only eating the muscle meats of these animals, you are creating an internal environment that your body is only used to seeing when food is scarce. It responds by preserving energy through the stress metabolism, inflammation, and hormones to suppress long-term health and metabolic rate.

So does that mean you should avoid muscle meats and only eat crazy foods like chicken feet, liver, brains, and bone broth?

Not at all, although those foods are all incredibly metabolic sources of protein that actually taste pretty damn good.

It simply means that you need to balance out the amino acids from the muscle meats with a good amount of the pro-metabolic amino acids.

Recommendations For Rebalancing Amino Acids:


The easiest way to balance out the anti-metabolic amino acids is simply to add a good amount of powdered gelatin or collagen to any muscle meats you eat.

Luckily, adding gelatin or collagen to any meat makes it taste absolutely incredible, which makes perfect sense. This is how we evolved to eat animals, and the fact that it tastes good is simply an evolutionary drive of your body to encourage you to eat more of what will help you (of course this is an entirely different tangent).

Just adding 10-15 grams of gelatin/collagen protein per 50 grams of animal protein is probably sufficient, but I recommend simply covering whatever meat you are eating with it.

For a delicious collagen rich seasoning try UMZU's zuBroth!

zubroth bone broth

On top of that, I highly recommend simply adding as many more pro-metabolic amino acid sources as you can to your diet (I sip on bone broth after my big dinner).

Be open to experimenting with organ meats, bone broth, and gelatin/collagen concoctions, along with other traditional ways of eating animals.

Organ meats, especially beef and veal liver, have many other incredibly important nutrients for good health like the fat-soluble vitamins, choline, etc.

Bone broth is incredibly tasty, and delivers a good hit of pro-metabolic amino acids.

And of course, adding powdered gelatin or collagen to meats and other foods is a very simple thing to get started with.

What About Other Protein Sources?

other protein sources

Now, a question you might have is, what about other sources of protein like dairy, seafood, eggs, and non-animal protein?

These sources are all “whole” animal sources and typically have a good balance of amino acids.

Dairy, specifically, has a lot of good nutrients, but also creates a bigger insulin response. For this reason, I like to save dairy for times of “growth”, like after a hard workout.

Seafood is great, and has a higher copper content that is important for the function of cytochrome oxidase, a crucial enzyme in aerobic respiration.

Eggs are nutrient dense and have choline to help the liver stay lean. Eggs do have PUFAs however, so do not go overboard with them.

Finally, I tend to avoid focusing too much on protein from non-animal sources, as these foods typically have other anti-metabolic features (like the PUFAs in peanuts or the anti-thyroid goitrogens in black beans).

Learn More: The Low Cortisol Lifestyle | UMZU's guide To Fighting Stress

How Much Protein?

how much protein?

Finally, we want to make sure that we are eating enough protein overall.

Generally, the fitness crowd tends to go extremely high in protein, while the RDA says that a staggeringly low amount is adequate.

I tend to see the very high amounts as not only unnecessary and inconvenient, but actually not optimal for metabolism since it means eating fewer carbs, and possibly a bigger cortisol response.

Going low is not good either though, as protein is critical for so many functions in metabolism.

I recommend hitting around 0.82 grams of protein per pound of body weight, which is plenty to support both muscle growth and metabolism.

If you are very overweight, you can use something like lean body mass instead of total weight.

Your protein should typically fall somewhere between 75-150 grams per day (less for smaller women, more for bigger men).

This might be lower or higher than what you are used to, but remember that going too high or too low can be detrimental for metabolism and hormonal health in general.

Key Points:

  • Avoid eating muscle meats or sources rich in the anti-metabolic amino acids (tryptophan, methionine, cysteine) without adding gelatin/collagen or a good source of the pro-metabolic amino acids (glycine, proline, alanine)
  • Experiment with more traditional animal foods that contain ligaments, organs and tendons
  • Bone broth is an excellent beverage to go with meals or drink as a soup
  • Seafood and dairy have a good balance of amino acids and are nutrient dense
  • Eggs should be included, but minimized because of PUFA content
  • Non-animal proteins should generally be avoided
  • Generally aim for around 0.8 grams of protein per pound of bodyweight


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