If there’s one macro nutrient the fitness industry just can’t get enough of, it’s protein. With energy bars, supplements, snacks, and meals in restaurants advertising themselves as “high protein,” it’s easy to get swept up in the craze around the nutrient. But, do you know everything there is to protein? Before we list out a few protein facts, it’s important that we first dive into its importance.
Why Is Protein So Important?
Half of our dry body weight is made up of protein. The brain cells, muscle, skin, hair, and nails are protein based. Our body breaks down protein into 20 different kinds of amino acids which are responsible for various bodily functions.. This process is called protein synthesis. So while protein is necessary for the body’s growth, development, and functioning, its importance goes up a notch when you’re working out.1
Why Do We Need Protein After A Workout?
When you exercise, your body releases epinephrine and nor-epinephrine, otherwise known as adrenaline. This makes the body enter the “fight or flight” state causing your heart rate and respiratory rate to increase. In addition to this, blood flow is diverted from non-essential systems (like the gastrointestinal system, reproductive system, kidneys, and skin), to the systems needed for survival (the skeletal muscles, heart, lungs, and brain).2
This response causes the body to mobilize glycogen (glucose storage) to increase the circulating blood sugar. It also breaks down fats. This causes protein synthesis to be suppressed and its protein breakdown (degradation) to increase. Once your body has depleted its glycogen stores, it takes energy from other sources like fat and skeletal muscle. Hence, if you exercise intensely, or for a long time, you will have a net loss of skeletal muscle protein. Resistance training and running demand the most of the skeletal muscle.3
Once exercise is over and there’s decreased glucose demand, your net protein breakdown slows and synthesis increases. And, the most important way of supplementing this process is by having a high dietary protein intake.4
Protein Facts That You Should Know
1. Each Person Has Different Protein Needs
If you follow a generic diet with high protein intake, then you might need to reconsider your food habits. This is because, protein isn’t one size fits all. The amount you need depends on your weight, age, and health. For an approximate, the recommended intake for a sedentary person is 0.75 g/kg for adult women, and 0.84 g/kg for adult men. The elderly need more protein to prevent sarcopenia.5
People who are looking to gain muscle mass and are engaged in weight training need to consume 1.2–2.0 grams of protein per kg of their body weight. Athletes in resistance training need anywhere between 1.0–1.7 grams of protein/kg of body weight, while elite athletes need 1.7 grams of protein/kg of body weight.6 7
Hence it’s important to have a diet chart designed just for your body and its needs. Meet a nutritionist or a dietitian before you increase or decrease your protein intake.
2. There Is Such A Thing As Too Much Protein
Our bodies can’t process excess protein. Instead it might impose a metabolic burden on the bones, kidneys, and liver. If your main source of protein is meat then it might increase your risk of coronary heart disease or cancer, owing to its saturated fat and cholesterol.8
It’s also important to space your protein intake out. Excess protein in one meal will be excreted by the body. So, optimize your protein intake by eating small amounts in every meal.9
3. You Need Different Sources Of Protein
Protein powder can’t make up for all your protein needs. Your body needs a variety of protein sources to make up for all the essential amino acids. Of the 20 essential amino acids, 9 need to be sourced from dietary intake as the body can’t make them on its own. These include histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
Foods that contain all of these essential amino acids are called complete proteins. These include meat, poultry, fish, dairy, seeds, and eggs. Incomplete protein sources include nuts, legumes, fruits, and grains. A balanced diet of all these sources is the best way to maximize your intake of all essential amino acids.10 11
A balanced diet consists of good quality and varied sources of protein. However, if you’re working out regularly and are confused about your intake, then it might be a good idea to consult a nutritionist. With the right amount of protein intake, you’re sure to reach your fitness goals in no time.
|↑1, ↑5, ↑9||Protein. Victoria State Government.|
|↑2||Di Pasquale, Mauro G. Amino acids and proteins for the athlete: The anabolic edge. CRC Press, 2007.|
|↑3||Emrick, Michelle A., Martin Sadilek, Keiichi Konoki, and William A. Catterall. “β-Adrenergic–regulated phosphorylation of the skeletal muscle CaV1. 1 channel in the fight-or-flight response.” Proceedings of the National Academy of Sciences 107, no. 43 (2010): 18712-18717.|
|↑4||Tipton, Kevin D., and Robert R. Wolfe. “Exercise, protein metabolism, and muscle growth.” International journal of sport nutrition and exercise metabolism 11, no. 1 (2001): 109-132.|
|↑6||Stark, Matthew, Judith Lukaszuk, Aimee Prawitz, and Amanda Salacinski. “Protein timing and its effects on muscular hypertrophy and strength in individuals engaged in weight-training.” Journal of the International Society of Sports Nutrition 9, no. 1 (2012): 54.|
|↑7||Protein. Australian Sports Commission.|
|↑8||Delimaris, Ioannis. “Adverse effects associated with protein intake above the recommended dietary allowance for adults.” ISRN nutrition 2013 (2013).|
|↑10||Protein. Harvard TH Chan.|
|↑11||Amino acids. US National Library Of Medicine.|