To keep your body in tip-top shape, you need to know some nutrition basics. It doesn't take a biology degree, just an understanding of what your body needs to function properly and where to find it.
Proteins, one of the six essential nutrients, is built from 20 different amino acids. The human body can produce the majority of amino acids, but nine of them must come from food sources.
As a consumer, you may just think of protein as protein—you get it from meat, dairy, and nuts, end of story. But that's not the case; not all protein sources contain all the essential amino acids, meaning you have to mix up the proteins you eat to get all nine. Vegans and vegetarians have to be especially precautious, as individual plant-based proteins tend to contain fewer types of amino acids.
The 9 Essential Amino Acids
Since the body can't synthesize the following amino acids, they're referred to as “essential,” meaning you must procure them from food or supplements. Each of these compounds plays a unique role in the body, as described below.
- Histidine– Histidine helps create histamine, a neurotransmitter responsible for immune response, sexual function, digestion, and sleep cycles. Histidine also helps maintain myelin sheaths, which serve as protective barriers around nerve cells.
- Isoleucine– Isoleucine is a three-branched chain amino acid. Branched-chain amino acids (BCAA) can be used as an energy source during exercise. Isoleucine, more specifically, helps with metabolism, immune function, and hemoglobin production.
- Leucine– Leucine, another branched-chain amino acid, helps with protein production and muscle repair. The body also needs leucine for regulating blood sugar, producing growth hormones, and healing wounds.
- Lysine– Lysine plays a role in protein synthesis, hormone and enzyme production, and calcium absorption. This amino acid also helps the immune system.
- Methionine– Methionine plays an active role in the absorption of certain vitamins and minerals, tissue growth, detoxification, and metabolism.
- Phenylalanine– Phenylalanine is essentially a building block for other amino acids, the building blocks of protein. Furthermore, it's needed to produce vital neurotransmitters like tyrosine, dopamine, epinephrine, and norepinephrine.
- Threonine– Like phenylalanine, threonine helps synthesize other amino acids. The body uses it to create proteins like collagen and elastin and to strengthen tissues and muscles around the body.
- Tryptophan– Though often associated with causing drowsiness (the nap after Thanksgiving turkey), tryptophan is needed to maintain proper nitrogen balance and is a precursor to serotonin, a neurotransmitter that regulates your appetite, sleep, and mood.
- Valine– Valine is the last of three branched-chain amino acids. Valine helps stimulate muscle growth and regeneration and is involved in energy production.
Protein Groups
The human body produces or uses more than 10,000 different proteins. But rather than researching specific proteins, it's beneficial to learn about groups of proteins with similar functions.
- Fibrous Proteins– Fibrous proteins such as collagen and elastin form muscle fibers, tendons, bones, and connective tissues in your body.
- Globular Proteins– Globular proteins, such as hemoglobin, are more water-soluble and are used to transport and regulate various nutrients in your body.
- Membrane Proteins– Membrane proteins, such as histones, help cells communicate with each other and transport molecules between cells and throughout your body.
A Balanced Protein Diet
The key to consuming enough of all the essential amino acids is diversifying your protein sources. Even on a vegan diet, you can find natural sources of all nine. Protein-rich foods include:
- Meat and seafood
- Eggs
- Dairy products
- Oats
- Quinoa
- Vegetables like broccoli, brussels sprouts, spinach, and asparagus
- Tofu
- Soybeans
- Nuts
- Seeds
- Beans
- Legumes
- Lentils
Common Protein Supplements
It is normal for people concerned about protein to take a protein supplement, usually a powder. Some people are vegetarian or vegan and want to make sure they are getting enough diverse proteins in their diets. Others take supplements to help build muscle. A few popular protein supplements include:
- Whey Protein Powder– Whey protein comes from milk and, as such, does contain some lactose, which many people are sensitive to. However, it is easily digestible and easily absorbed by your body. Whey is a complete protein, meaning it contains all the essential amino acids.
- Mixed Plant Protein Powder– These vegan-friendly supplements contain protein from two or more plant-based protein sources such as peas, hemp, brown rice, and flax seeds. By combining ingredients, most mixed plant protein powders contain all the essential amino acids.
- Collagen Powder– Hydrolyzed collagen helps to strengthen bones, joints, skin, hair, and nails. Because the body's natural production of collagen slows with age, it's become a popular supplement for seniors.
Pro Tips for Protein Consumption
Most people know that protein is an essential nutrient for good health. However, it is worth taking some time to make sure you are getting all of your essential amino acids in. Make sure to eat a variety of protein-rich foods so that you can live your best life.