Updated: Jul 9, 2019
Proteins are all the buzz, especially in the fitness industry lately! Understanding what protein is, how much to consume, protein sources, etc. can help you make healthier choices every day. So follow along to find out protein basics.
What is Protein?
A protein is a macronutrient that is essential to human life and function. Proteins are responsible for building tissue as we grow, and maintaining tissue as it constantly deteriorates. They also develop hair, skin, nails, bones, tendons, and ligaments. They break down food for energy, play a huge role in blood clotting, help carry oxygen in your blood, and the list goes on and on!
Each protein contains one or more amino acids. Amino acids are the building blocks of proteins. The body uses each of these amino acids for various protein functions in the body.
Essential Amino Acids
Of the 20 amino acids, 9 are essential amino acids. Essential amino acids cannot be formed by your body like other amino acids; thus, it’s necessary to consume them so that they can be used to maintain your body function!
These amino acids include:
With a lack of amino acids, your body will begin to have trouble carrying out basic everyday functions!
Complete vs. Incomplete Proteins
A complete protein contains all of the essential amino acids. These sources include eggs, meat, fish, and poultry. Rounding out the complete proteins are a few vegetable sources; including most popularly soy protein (tofu, tempeh, soybeans), quinoa, and buckwheat. So basically, eat an egg, eat a chicken breast, eat a block of tofu, and no more thinking necessary- you are getting some of each of those essential amino acids you need.
Incomplete proteins, on the other hand, are food items that have some of the essential amino acids, but not all. However, these incomplete proteins can be combined with other incomplete proteins to form a complete protein!
Making a Complete Protein Out of Incomplete Sources
In order to get the correct combination of essential amino acids from incomplete protein sources- it is recommended to consume 60% of protein from grain products, 35% from legumes (beans, nuts, etc.), and 5% from leafy green vegetables. Which can be eaten over the course of a day and don’t have to be eaten all at once (1).
For example, to consume 56 grams of protein from incomplete sources, you could do so by eating:
1 ¼ cup beans
¼ cup seeds/nuts
4 slices of wholegrain bread
2 cups of vegetables (1 cup leafy)
2 ½ cups of grains (brown rice, oatmeal, etc.)
Include incomplete proteins in your diet by using the percentages above as a guide to be sure you’re getting the right nutrients! And remember, it’s also possible to use incomplete proteins to fulfill just a portion of protein needs, fulfilling the rest with complete sources.
How Much Protein Should You Consume?
The Food and Nutrition Board of the National Academy of Science has released Recommended Dietary Allowance (RDA) recommendations for protein and other macronutrient intakes (2).
These recommendations are liberal and reported in safe excess so that generally healthy people following the recommendations do not experience nutritional deficiencies. However, these averages are based on the needs of an extremely varied population, not strict recommendations for individuals.
For an average healthy adult, it’s recommended to consume 0.8 grams (g) of protein per kilogram (kg) body mass daily. For a 150 lb (68 kg) person that’s about 54 grams per day.
However, for athletes or adults who participate in intense training, a study in the Journal of Sports Science, recommends increasing protein uptake 1.3-2.0 g/kg. For a 150 lb person that’s 82-136 grams of protein per day!
If you are looking for a recommendation for specific individual requirements please consult with a registered dietitian. A registered dietitian is qualified to tell you what’s optimal for you specifically.
Which Source of Protein is Best?
Animal sources are generally rated higher for protein because they do have all of the essential amino acids. However, that doesn’t mean that plant sources aren’t adequate when properly consumed or combined. In fact, according to research, amino acids from plant and animal sources when consumed properly provide comparable results when it comes to building and maintaining muscle (3).
Overall, animal sources are higher in saturated fats than their vegetable counterparts. There have also been multiple clinical trials involving soy protein which have shown that replacing as little as 20 grams of animal protein sources with soy protein resulted in decrease in blood pressure, decrease in plasma homocysteine levels, decrease in triacylglycerol levels, decrease in LDL (bad) cholesterol, along with no reduction in HDL (good) cholesterol(4,5,6)! Which is huge! For those who have elevated blood pressure or cholesterol, introducing some vegetarian protein to the diet could yield positive results.
Ultimately, how you choose to consume protein in your diet is up to personal preference. If you could use improvement in this area of your diet, don’t stop here! Do some more research or talk to a registered dietitian to get some sound advice on what you should be eating.