How many of us are under the impression that the more protein I take in during strength training, the more muscle mass I will gain? The answer, too many of us! It is just not true. It is no secret that proteins make up our muscle tissues and without protein, our tissues would atrophy and our body would literally consume itself for survival. Proteins are found in all bodily cells and are polymer chains of amino acids, the building blocks of life. There are 9 essential amino acids (AA’s) the body must consume and cannot be biosynthesized by the body. The average diet contains all 9 AA’s and then some. Dietary sources of protein come from both plant and animal sources.
But how much protein is too much? How does the body handle excess protein? The recommended Dietary Allowance (RDA) is 0.08 grams per kilogram of body weight. This is the amount of protein needed for healthy functioning and does not account for more than minimal activity levels. Now, the best way to determine the number of grams of protein needed for healthy functioning is to take your body weight in pounds and multiply it by 0.36. This number is the minimal intake for a sedentary person with very little activity. It is well known that as little as 10% of your total daily caloric intake should comprise of protein. That said, most of us are consuming 6-10% or more than that from both plants and animals.
Although there is some debate as to what the exact figures should be, it is generally recommended for athletes to consume more protein than sedentary people for purposes of muscle and tissue regeneration. Endurance athletes should consume between 1.2 and 1.5 grams of protein per kilogram of body weight. Strength training individuals should consume between 1.5 and 1.8 grams of protein per kilogram of bodyweight. Females should typically consume roughly 15% less protein than males using the figures referenced above. Now, when you do the math for your intake needs, you will most likely find that you were consuming more than necessary when combining all plant and animal foods eaten. So what happens to the excess protein?
It is a common misconception that excess protein automatically turns to fat and is stored as such. The reality is that excess protein can’t be stored as such and will undergo one of two turnover processes (degradation and/or synthesis). The first process involves degradation into urea via the liver. The liver deaminates the amino acids (already broken down from protein via stomach and small intestine enzymes) by converting the nitrogen atom to ammonia. Because ammonia is toxic to the body, the liver then continues its degradation by converting the left overs to urea via the Urea Cycle and then ultimately excreted via the kidneys. Simple, right? The problem here is that excess urea excretion is known to be a cause of kidney stones due to the excess calcium excretion to normalize urine pH. On the other hand, the liver can take excess amino acids and convert them for energy use by forming glucose and ultimately glycogen via glycogenesis (glucose molecules that are stuck together). From here, if the liver storage centers are full, the excess glycogen can be converted to fatty acids and ultimately stored as adipose tissue.
So yes, it is possible to take in too much protein and yes, it is possible for that excess protein to be converted into fatty tissue. We would suggest you see a nutritionist or other informed practitioner to address your specific questions and get you on track for success during your training. We also recommend you learn more about these processes to understand you need from your diet to function at your best. Future blogs will contain more information regarding dietary other informational material to help you move better.