Let’s Talk About Protein
By Briana Ururen
The word protein means “of high importance.” Isn’t that the truth! BUT, if not used correctly, you may not receive the full benefits of the protein you consume. So I’m here to share more information so you can make wise protein choices.
Proteins contain carbon, hydrogen, and oxygen atoms, just as carbohydrates and fats do. What sets them apart is that proteins also contain nitrogen atoms. Not surpringly, nitrogen is an element that is essential to growth and reproduction.
Proteins are vitally important because they form integral parts of most of our body’s structures including the muscles, skin, and bones, as well as participating in vision and blood clotting. In fact, almost every cell in the body contains some protein!
But, proteins in foods do not directly become body proteins like muscles. Instead, the proteins we eat supply the body with amino acids so that the body can make its own proteins.
That means amino acid composition is important. A cell must have all the needed amino acids available at the same time to make proteins. That means that in order to prevent protein breakdowns in the body, dietary protein must contain at least the nine essential amino acids (histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine). These amino acids are considered “essential” because the body cannot make them or cannot make enough of them; therefore it is essential that they be supplied by your diet.
High quality proteins are ones that contain all the essential amino acids and these are usually foods derived from animal products s such as meats, poultry, fish, eggs, cheese, yogurt and milk.
Complementary proteins are two or more dietary proteins whose amino acid sequence complement each other so that when essential amino acids are missing in one, the other will supply it.
An example of this complementing system could be black beans and rice, or whole wheat bread and peanut butter.
Protein quality is extremely important and there are two main factors that influence it: its amino acid composition, as discussed above, and the protein’s digestibility.
Digestibility depends on the protein’s source as well as the foods that were eaten with it. Some proteins are more easily digested by the body, and are therefore more ‘bioavailable’ or usable. Most animal proteins have a high digestibility – around 90-99% – whereas plant proteins are less digestible at 70-90%, with the exception of soy and legumes which are also around 90%.
Reference protein is a standard for measuring food protein quality and is determined by comparing the amino acid composition with the essential amino acid requirements of preschool age children. It has been said that if a protein will effectively meet the needs of a child’s growth and development, then it will be adequate – if not exceed – the requirements of most older children and adults.
Proteins can also help maintain blood glucose levels when carbohydrate intake is insufficient; however, it is at the expense of our lean body tissue.
Since proteins are broken down by our body before they are absorbed, a common misconception is that consuming predigested proteins (sold as “amino acid supplements”) will keep the body from overworking. Be wary of buying amino acid supplements or protein shakes containing predigested proteins. Although this sounds like a good idea, it is not completely accurate. Our digestive system actually handles whole proteins better than predigested ones because it is able to break down and absorb the amino acids at a rate that is more accurate for the body’s use.
Protein can be very beneficial to your body and should be an essential part of your diet, especially if you are exercising. Make sure to choose high quality or complementary proteins instead of supplementing with predigested proteins when fitting them into your diet, and remember that the human body contains around 30,000 different kinds of proteins (some of them haven’t even been studied yet) so this is just the tip of the iceberg!