Despite the wealth of knowledge available over the world wide web, it is still shocking the amount of misinformation that exists in regard to many facets of health and fitness. Of the most persistent of these myths the ones surrounding protein are still some of the most common, unsupported and often ridiculous.
This first one isn’t so much a myth but a misunderstanding; people have a tendency to focus on the amount of protein they eat in the diet and of course, the amount of protein you eat is important, however one often neglected area when considering protein intake is protein quality. So what is protein quality? Well it relates to a couple of things; firstly, the spectrum of amino acids that are found within a food source. Meat and dairy are considered the highest quality proteins from this perspective as they contain a wide spectrum of amino acids including all the essential amino acids. They are in effect a complete protein source. Many plant sources are incomplete protein sources so for those who follow a vegetarian or vegan diet, it is essential to have an understanding of the amino acid profile in foods in order to make sure you have enough essential amino acids to support normal healthy function. Forget building muscle, this is purely for health benefits.
The second measure of protein quality is its leucine content. Leucine is a key regulator of muscle protein synthesis; in fact, it is the only amino acid regulator. Leucine is an indicator of protein quality because it is typically found in large amounts again, in meat and dairy, and acts as a signaller to build new protein in the presence of the amino acids that are found in quality protein sources. Without this leucine signal protein synthesis is not triggered and without the complete amino acid profile the new protein cannot be created.
Again, most plant sources are deficient in leucine, so supplementation with high leucine supplements for those following a vegetarian/vegan diet and looking to build muscle, is pretty much essential. What about for those just looking to maintain health? Well, higher quality protein is better for recovery for those who exercise regardless of goal, so for recovery purposes it is still something to consider. For those who don’t exercise regularly, it could be argued that leucine content would be less of a concern, however even for general health, muscle protein turnover happens on a daily basis. Quality protein sources have been shown in many populations to help preserve lean muscle tissue and improve muscle function, so at least some attention to protein quality not just quantity needs to be given for its long-term health benefits.
This sort of leads me onto the next ‘myth’ that protein is just for bodybuilders. Hopefully you can see from the above paragraph that protein is ESSENTIAL and certain amino acids are ESSENTIAL. Essential does not mean for essential bodybuilders or athletes; it is essential for health. Of course the amount of protein you require will differ depending on your goals and the daily demands placed on the body. Remember protein is more than just muscle; enzymes that are responsible for every function in the body pretty much without exception are, you guessed it, made of proteins and need constant renewal. Forget the muscle building effects for a moment; protein also gives a feeling of satiety (fullness) more so than many other foods. It also helps preserve lean tissue which supports metabolic rate and maintains function and long term quality of life. Regardless if training takes place or not, a vast majority of people would be healthier and maintain better eating habits if including a little (or a lot) more protein in their diet.
On that note, protein will not make you bulky (for the millionth time!!) whether you grow muscle quickly or not, is dependent on things like the training stimulus, overall calorie intake and the levels of key hormones in the body. You can eat as much protein as you want and if you don’t train like a bodybuilder and eat large amounts of calories, then you 100%, no questions asked, do not need to worry about getting ‘bulky’ or too muscular. For fat loss diets an intake of around 2.5g/kg of lean body mass is suggested; this is even above what would be recommended for strength athletes and bodybuilders… Why? Well, for all the health reasons described above! Even for those on this amount of protein and performing resistance training, as long as calories are not high then rapid muscle gain will not take place and for most people, resistance training will improve their muscle quality, give them better function, health and the overall ‘look’ they desire once they get over this irrational ‘bulky’ fear.
But isn’t too much protein bad for your kidneys? The kidneys are indeed involved in protein metabolism and when the kidneys get ‘worked’ they elevate enzymes that help protein metabolism. It was thought that these elevated levels of certain enzymes and other metabolites of protein are a measure of healthy kidney function and indeed they can be, which raised concerns of high protein diets. However, multiple wide scale studies have shown that despite some of these markers of kidney health being elevated that these are not necessarily indicators of disease or dysfunction (there are other more integral indicators of function that are not elevated with protein intake) and are a normal, non-health related response to increased protein intake. They have unanimously declared that high protein consumption is in no way problematic to health and normal kidney function unless there is an underlying medical condition. This confusion over kidney health is also commonly found with Creatine, as it elevates levels of creatinine which can be an indicator of kidney dysfunction, however it is also a normal, completely non-indicative by-product of Creatine (and protein) metabolism and is also elevated as a normal response to resistance or intense training, when muscle tissue is broken down.
But your body can only absorb so much protein right? No. Wrong. Your body can digest and absorb as much protein as you can throw at it (although I wouldn’t advise this for the digestive stress!) Does that mean it will all be used to build muscle? No, your body will have a maximal rate of protein synthesis that once we provide the raw material for in the form of amino acids, any excess amino acids will be converted to be used as energy and only stored in small amounts. The body can only ‘use’ around 20-30g of protein every few hours for protein synthesis, so in order to maximise your protein synthesis, you’re better off eating your protein in smaller portions every four or so hours than having one or two large protein meals a day.
In conclusion, high protein diets are not just for bodybuilders or athletes; They can help promote health, fat loss and prevent age related muscle-wasting. Protein is not inherently bad for your body and although the confusion is understandable, it is in large unfounded and something you shouldn’t be concerned about unless you have had previous kidney issues. Oh and finally, just in case you didn’t get the message… Protein on its own will 100% NOT make you bulky!