What Does Protein Actually DO In Your Body?
by Dani Taylor
Protein is often thought of as the golden child of the three basic macronutrients the body requires (protein, fat, and carbohydrates). Unlike carbohydrates and fats, you never see protein vilified in news about health. In fact, to hear some “health” outlets tell it, all you really need to eat is protein and nothing else! This definitely isn’t true - carbohydrates and fats are also critical - but protein is seen as the all-star macronutrient for good reason, especially as it pertains to fitness.
Protein is important for every cell in the body. It is used to create and rebuild tissues, and to make enzymes and hormones that control metabolism. So although we may not need as much protein as the media would lead you to believe, we definitely require protein to live and thrive.
It is beneficial, though, to understand just what protein is doing in the body, how to get it, and how much you should eat daily. Here are just some of the ways protein performs in the body…
In your brain: Eating protein raises the levels of another amino acid called tyrosine, which prompts the brain to manufacture norepinephrine and dopamine, other kinds of chemical messengers in the brain. Not as well known as serotonin, norepinephrine, and dopamine can keep you energized because they promote alertness and activity.
In your muscles: Protein is the building block of your muscles. After physical activity, protein is essential for the development and regeneration of muscle cells. The more muscle you have, the more calories you burn at rest as well!
In your immune system: Protein is vital to build and repair body tissue and fight viral and bacterial infections. Immune system powerhouses such as antibodies and immune system cells rely on protein. Too little protein in the diet may lead to symptoms of weakness, fatigue, apathy, and poor immunity.
Inside of your cells: Proteins make up the enzymes that are responsible for catalyzing several biochemical processes that support metabolism, muscle and nerve activity, and even breathing.
Hair, Skin & Nails: Protein helps hair, skin, and nails build structure. Without enough protein, you may have brittle hair and nails and dull skin.
Hormones: Protein helps make up many of our hormones, which have essential functions for fertility, development and growth, and control of appetite.
Bones, Tendons & Ligaments: Collagen and elastin are protein types that provide bones, tendons, and ligaments with structure.
Proteins are made up of amino acids, which form long chains and have distinctive body functions. While there are 20 amino acids in all, only 11 can be produced by the body. The remaining nine are considered essential amino acids, which must be consumed by your diet.
The bulk of plant foods do not contain all 11 amino acids. But you don’t need to eat all 11 amino acids at once in order to reap the benefit of all of them! When consuming a variety of plant-based protein foods, you do not have to worry about not eating “complete proteins” in order to be getting all the amino acids you need. Rice and beans, nuts, whole grains, tofu, tempeh, seitan, nutritional yeast, vegetables, and seed are all great things to consume for a well-rounded amino acid intake. It is more than possible for vegetarians and vegans to ingest ample total protein.
Protein digestion begins in the stomach, where it is broken down by stomach acids and enzymes called proteases. This continues into the small intestine, where additional enzymes break proteins into individual amino acids. These amino acids are absorbed through the intestinal wall and make their way into the bloodstream, going where they are needed throughout the body.
So how much protein should you eat? A good rule of thumb is to eat between 15-20 percent of your daily protein calories, but based on your lifestyle, individual amounts will differ. For example, anyone who is involved in more physical sports, such as intense weightlifting, will generally require more protein than someone who is sedentary.
According to some studies, the body can consume 25–35 grams of protein per meal. Thus, spacing your protein consumption over the day is more effective rather than attempting to eat all of your protein at one meal.
Just because adequate protein is good, that doesn’t always mean that more is necessarily better. Excess protein, just like excess carbohydrate or fat, is retained as fat. Many people believe that eating too much protein defies the laws of thermodynamics (meaning that many people think you cannot gain body fat by eating too much protein), we assure you, this is not the case.
To get an idea of how much protein you’re consuming, you can use an app like MyFitnessPal or a different type of food journal. Try reaching out to a registered dietitian or nutritionist who can help with individualized advice if you need further input.