When discussing protein we must first separate the fact from fiction
There are many benefits to consuming protein but there are also many supposed benefits that do not stand up. Eating protein will not increase your muscle size or improve strength. Adding protein to your diet will not help you lose weight, it will cause you to gain weight (replacing fat or carbs with protein is another matter).
Just because something that you are eating is high in protein doesn’t mean that it is healthy. Finally, eating a high protein diet will not harm your kidneys, unless you have a pre-existing condition.
So, on to the reasons to eat more protein…
1. Protein helps promote loss of body fat
A study by Pasiakos et al (2013) found that consuming twice as much protein as recommended protects fat free mass (everything in your body except fat) and “promotes the loss of body fat during short-term weight loss”  Another study by Layman et al (2003) found that increasing the proportion of protein to carbs would produce positive effects on body composition in women .
Obviously you can’t just add more protein to your diet and expect to lose weight, you would need to lower the calories from the other macronutrients (fat and carbs) to fit it in.
Or you would risk gaining weight due to the extra calories.
The Layman study is particularly interesting as it found that increasing protein when in an energy restricted diet, meant that the subjects would lose body fat whilst maintaining lean muscle. Which is pretty much the goal of anyone who has ever dieted.
If you want to look ‘toned’ you need to have a low body fat percentage, whilst keeping your muscles from getting smaller. High protein diets can help you with that.
2. Protein will improve thermogenesis
Have you noticed that when you exercise your body temperature rises? Or if you have eaten a big meal you feel warm? How about when you come indoors when it’s cold outside and you are ridiculously warm after a couple minutes?
This is thermogenesis
Or to put it simply the production of heat. Basically, whenever you get all hot and sweaty this is due to your bodies increased temperature. If you spend more of your day like this, your metabolism will be higher and your body will use more energy, meaning that so long as you don’t consume more calories than usual you will lose weight.
When people talk about metabolism they are describing three factors
– Your Basal Metabolic Rate which is the amount of calories your body requires for you to function normally (sleep, breathe, think, regulate body temperature).
– Physical Activity, which is the amount of calories you use when moving, lifting, standing.
– The thermic effect of food, so whenever you eat something it will require energy to digest your food, transport nutrients etc.
Protein, fat & carbs
Protein, fat, and carbohydrates are all processed differently and all require different amounts of energy. Fat is the easiest macronutrient to process, carbohydrates are a little harder – 3% and 7% respectively, whilst protein is the hardest and will produce a thermic effect of 30% .
So a high-protein diet will improve thermogenesis which in turn increases your metabolism. A study by Johnston, Day, and Swan (2002) found that thermogenesis was increased 100% on a high protein/low fat diet when compared to a high carb/low fat diet in women .
3. Dietary protein provides essential amino acids that the body cannot produce
As stated by John Berardi in “The Essentials of Sport and Exercise Nutrition”  Amino acids that make up our proteins are responsible for pretty much everything in the body (muscles, ligaments, hormones, and enzymes to name a few). Amino acids are split up into 2 groups, Essential and Non-essential.
There are 12 non-essential amino acids that are formed in the body and do not need to be obtained from our diet, and 8 essential amino acids that cannot be formed in the body and need to be obtained from our diet.
Examples of these essential amino acids are Leucine, Lysine, Isoleucine(also known as BCAAs or Branch Chain Amino Acids).
Without adequate protein intake through diet, these amino acids will not be produced. Also, unlike fats and carbohydrates, protein is not stored in the body so you need to constantly top up your amino acids every day. If you do not, your body will begin to cannibalize enzymes and other proteins in the body which can cause severe problems long term.