If there’s one macronutrient that the fitness minded folks focus on more than the others – it’s protein. It’s like we just can’t get enough. But how much do your really know about protein? You can probably list of a list of 10 good protein sources off the top of your head, but lets dive a little deeper.
WHY do we need protein?
Protein is essential for growth and recovery of muscles when you’re focusing on gaining muscle. It preserves lean body mass when you’re focusing on cutting body fat and spares muscle breakdown during exercise.
So WHAT exactly is protein?
Proteins are large molecules called polypeptides. Amino acids are the building blocks of protein (remember that from high school biology?) There are 22 amino acids that are biologically important to the human body. Proteins make up about 75% of the dry weight of most of the cells in your body, so makes perfect sense as to why we as athletes focus so highly on protein.
Protein is rated into 1 of 2 categories – complete and incomplete. Incomplete proteins lack at least one of the 9 essential amino acids, like plant proteins. Essential amino acids CAN NOT be made by the human body and consist of histidine, isoleucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. Thus we need to get these from our diets or from supplements like CON-CRET AMINO. Conversely, complete proteins contain all of the 9 essential amino acids in amounts sufficient for muscle maintenance and “normal” growth rate. Completely proteins include eggs, milk, milk products and most animal proteins.
HOW much protein should you take in?
This is where things get personal. You’re going to hear some people say 1 gram for ever pound of body weight, you’re going to hear people say to double that. You’re going to hear no more than 40g per meal. In short… there is no ONE right answer. It depends on a myriad of things from your body composition to your activity level to your genetically inherited tolerance level to digesting protein. If you’re not taking in enough protein, you’re putting yourself at risk for sacrificing muscle mass. Too much, and the protein is converted to fat, increases toxic blood ammonia and uric acid as well as leaves you pretty darn constipated. The Recommended Daily Allowance (RDA) is 0.8 grams per kg of body weight. Now this is assuming you’re of an average weight and activity level. However, for athletes aiming for 1.5-1.8 grams per kg body way is recommended – DOULBE the the RDA for the average folks. Then you take bodybuilders into consideration and most typically double that amount! So to summarize 0.8g/kg body weight for the average person, less if you are overweight, 1.5-1.8g/kg for athletes.
The important thing to remember is that NOT ALL PROTEINS ARE CREATED EQUAL!!! Proteins receive a Biological Value rating which in short gives a value of the proportion of protein from a food source that can be digested and used in protein synthesis in our cells. This all depends on the ratio of nitrogen absorbed by the body from protein, and the nitrogen excreted. The higher the BV rating, the more usable the protein source is for your body. Since this is essentially a percentage, going over 100% doesn’t really make sense. You can’t absorb 137% of the protein from one source, however due to the way the BV level is calculated, it is possible to have a BV rating over 100. So if you ingest 24g of protein from a source that has a BV rating of 100, your body will use all 24g protein. If you ingest 24g protein from a source with a rating of 75, your body will be able to use only 18g of that protein. Below is a chart showing several common sources of protein for your reference. Choose wisely! 😉
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