At some time in your life you’ve probably heard that protein is important to eat. But most times the advice ends there. To ensure adequate protein consumption it might help to understand a few reasons why and possibly what type of protein is best.
More accurately it’s the amino acids…
All cellular and tissue repair in your body is dependant on proteins derived from amino acid synthesis. Amino acids are found in food and synthesized from within your body. We know of 20 amino acids all playing various roles in protein synthesis, 9 of these amino acids are considered essential amino acids (EAAs) while the other known 11 are non-essential amino acids (NEAAs). Although when certain diseases or health states are present, many NEAAs become essential. And since you actually never know or schedule those events, non-essential is a bit of a misnomer.
The amount and type of each amino acid requirement vary greatly. Certain types have a 10x greater demand than others. The amount and type of amino acids occurring in different foods also vary. And since all lifestyle factors play a role in each individuals requirements, it’s important to vary your protein sources and consume adequate amounts to ensure a good supply across the range of amino acids.
The focus is on protein consumption but only because protein gives the body the amino acids that it really needs. Amino acids do not occur in isolation. When you travel into nature to look for amino acids, the best source of EAAs all have either a mother or a face of their own. All plant based proteins are missing EAA for humans. This is not a slight on plant protein, just a natural occurring condition. Animal protein wins in quality, density, bio-availability and ability to sustain life without supplementation.
Thermic Effect of Food (TEF)
TEF represents the energy demand from the food eaten to be digested. A specific effort is required of your body to digest, absorb and metabolize food. That effort isn’t the same for all foods. Of the three macronutrients Fat, Carbohydrates and Protein, protein has the greatest TEF.
- Fat: 0-3% TEF
- Carbohydrates: 5-10% TEF
- Protein: 20-30% TEF (winner! winner!)
Average TEF for a healthy adult eating a standard omnivorous meal is around 10% of caloric intake. But many variables play a factor in this; lean body mass, meal size and composition, temperature, mood, quality of chewing, digestive enzyme state, etc.
A larger meal takes longer to digest, therefore has a greater TEF. The more lean mass you carry, the more your body spends time processing food to extract nutrients. And the meal composition matters as macronutrients have different TEFs.
There are many variables determining the TEF, and trying to calculate it exactly isn’t the point. The point is protein leverages the laws of thermodynamics in your favor when it comes to positive contribution to health, wellness and appetite control.
Protein is the most satiating macronutrient. The reason why isn’t exactly clear, but we do know that hormonal activity elicited from eating protein has huge impacts on our health.
Far beyond caloric intake, food sends chemical messages to your cells about the state of the environment. Messages like, is there sufficient nourishment to support life? Is there sufficient nourishment to thrive? Is this place safe and secure. Are threats around trying to harm me. What season is it? And many other things we don’t fully understand.
When our meals contain high quality, bioavailable protein our EAA requirements are more likely to be met. Additionally, the vast majority of our vitamin and mineral requirements are met. These factors plus many others contribute to healthy hormonal production, produce signals that reduce your hunger cravings and leave you feeling satisfied that you’ve eaten enough, and informs your brain sufficient nourishment is available. You eat less often and avoid “hangry” feelings.
Recycle, reuse and reduce waste
Within your DNA are blueprints to over 25,000 protein-based compounds that are essential to functional life. Protein’s importance is paramount, said simply, if you don’t eat protein, you die. If you eat too little protein for an extended period of time, you will survive but show signs of weakness, impaired immune system function, lethargy, bone loss, hormonal imbalances and a host of all kinds of less-than-desirable things.
You want to fill your amino acid pool or “protein bank account” to the brim and keep it maintained. It doesn’t need to be full to the brim constantly, but a positive balance is the goal. A nice ebb and flow seems to be the way to go. Fill it up by maximizing lean muscle mass and eating proper amounts. And run it down a bit by overnight fasting or periodically skipping a few meals.
As your body uses amino acids, it withdraws from it’s account to cover the bill so to speak. The account gets replenished by both the protein you eat (feeding) and recycling and restructuring existing proteins in the body (during fasting). Your body is constantly breaking down damaged and old cells, recycling and rebuilding the structures as needed. It’s a constant protein turnover. This is an amazingly efficient system that keeps the body regenerated with new healthy cells. Out with the old and in with the new!
The only ESSENTIAL macronutrient
I’m talking about fats, carbohydrates and protein.
Putting things together and viewing through a pragmatic prizm…your body needs
- Two (2) essential fatty acids (EFAs)
- Only ~ 130g glucose for your brain
- A large amount of EAA’s
- Varying amounts of EAA’s
- Varying kinds of EAA’s
Only two fatty acids cannot be synthesized in the body making those two essential to consume (EFAs). You need fat for healthy hormonal activity and transportation of certain vitamins and minerals. The amount required of these fats is very low and the proliferation of them in our food sources very high. This makes it very difficult to create a deficiency of fatty acids.
It’s true that your brain has a glucose requirement. This does not mean you need to consume glucose as is so commonly mis-interpreted. The daily requirement of about 130g is easily produced by a healthy functioning liver via gluconeogenesis. An additional benefit of protein!
And finally, with all of the body’s many functions dependant upon protein, it’s easy to make the case that protein is the only essential macronutrient.
References available upon request.