Protein – the most important macronutrient for muscle gain and retention

October 1, 2019

All calories in your diet come from only three macronutrients: Proteins, Carbohydrates and Fats, each macronutrient (macro) plays a different role in your body. Previously we discussed carbohydrates, next will focus on fat.

The Law of Thermodynamics – you consume excess calories you gain weight: you consume less calories you lose weight. This simple Law is great when losing weight, but to optimize performance and body function we must understand that simply cutting Macronutrients (calories) is always going to be at the expense of losing the qualities of that macro. For instance, if I eat an 800 calorie diet of pizza my body is going to respond very different than to an 800 calorie diet of greens, lean protein, healthy fats and carbohydrates. If any macronutrient is at a large deficit you will feel the physiological difference, having too low fat can cause poorer anabolic hormone environment. If carbohydrates are too low your energy levels will suffer and you risk losing muscle mass. Too little protein? Loss of muscle mass and ability for growth. Hence the need for a balanced macronutrient diet.

Two things to consider with macro-balancing: 1. What is the physiological need 2. How important are these needs in a ranked priority order.

Protein – the most important macronutrient for muscle gain and retention, about 1g of protein per pound of body weight is best for most people. Protein provides the building blocks for muscle growth and supplies the amino acids needed to reduce muscle breakdown. Protein builds new muscle AND saves existing muscle; both function are necessary for maximizing muscle and minimizing fat. Muscle is made out of protein and is therefore the most important macronutrient for body composition purposes.

The minimum daily intake for people on a mission to keep muscle and lose fat is .6g/lb of body mass – this is a MINIMUM, anything less WILL result in muscle loss – this also means that you likely have good genetics on your side, you are timing your protein intake steadily throughout the day and/or you have a very hypercaloric diet, receiving enough energy from carbohydrates and fat (not good for cutting fat). The opposite end of the spectrum is, excessive intake of protein- this excessive ceiling is likely above 1.25g/lb of body weight. It would take a HUGE excess amount of protein, on a regular basis, but having an excessive intake can result in damage to the kidney – do not fear this as it would take a huge excess to cause such a problem, but it should be addressed so you don’t just say, YAY ALL THE PROTEIN!!

Optimal Intake (as seen on your templates) is between 0.8g and 1.0g per pound of body mass for those individuals who exercise and are looking for lean muscle. Any value that strays far from this range will struggle with the balance of building muscle and sparing muscle while burning fat – #goals.

Our templates make this science easy – but, I also think for many of us, knowing the “whys” really helps to keep us on track. It is easy to say, “ehhh ill sub out this for that” but if you have the knowledge about timing, portion sizes, etc. it helps you to stay focused.


The Renaissance Diet – A Scientific Approach to Getting Leaner and Building Muscle, Dr. Mike Israetel with Dr. Jen Case and Dr. James Hoffman


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