All protein is made up of amino acids that chain together to form a larger molecule. Protein powders are no exception—they are also made up of amino acids. However, protein powders on the market can vary greatly in terms of amino acid content. When choosing the right protein powder, it is important to have a general understanding of amino acids and the type of amino acids each product contains. Let’s take a deep dive into the benefits of amino acids and why the amino acid composition is important in choosing a protein powder.
What are Amino Acids?
Amino acids are the building blocks of protein. Protein is a large molecule that consists of multiple amino acids chained together, then folded up into various shapes. The types of amino acids present and the order they are found in determines the function of the protein. For example, a protein used for building new muscle would have a very different amino acid composition from a protein to be used as an enzyme. The order and type of amino acids determine the destiny of the protein molecule.
There are 20 amino acids used in the human body. The body can make eleven types of amino acids on its own, from either other amino acids or nutrients. However, nine are considered “essential” in that they must come from food. The nine essential amino acids are: leucine, isoleucine, lysine, methionine, phenylalanine, threonine, histidine, tryptophan and valine. Each of these amino acids has a specific daily recommended intake.
Many foods contain some amino acids, but only a few foods have all nine. When a food has all nine amino acids it is considered a “complete” protein. When it is lacking one or more it is an “incomplete” protein. Animal foods, such as milk, poultry, fish and meat, are all complete proteins. Plant-proteins, such as beans, nuts and seeds, are incomplete proteins. The only exception is soy, which does have all nine essential amino acids. Quinoa and bulgur do have all nine essential amino acids, but the quantity is not high enough for those to be considered “complete” proteins.
In order to meet your daily amino acid needs, you will have to eat a variety of foods. You can meet your protein needs with plant foods alone, but it will require some planning and knowing about complementary proteins. Complementary proteins are foods that together form a complete protein. For example, beans are low in methionine, whereas rice is low in lysine. When eaten together, rice and beans make a complete protein because the amino acids in one fill in the gaps in the other. These complementary proteins do not even need to be eaten at the same meal, as your body can pull the amino acids it needs from your diet.1
The easiest way to meet your daily protein needs is to eat a high protein food with each meal. For optimal nutrition, you should vary between plant and animal sources. Unless you are a strict vegan, there is no need to worry if you are getting enough of each of the essential amino acids when you eat a varied diet.
Benefits of Amino Acids
Amino acids have many health benefits. Since they are the building blocks of protein, they play a role in muscle growth, enzymatic reactions, tissue repair, nutrient absorption, immune function and proper digestion.
Each individual amino acid also has some of its own unique benefits. Here are a few of the highlights:
- Valine is one of the branched-chain amino acids that helps with muscle growth.2
- Phenylalanine is a precursor to multiple neurotransmitters that may help with mood and sleep.3
- Threonine is part the structural proteins of the skin, collagen and elastin. It also helps the body use fat and is needed for healthy immune function.4
- Methionine is needed for detoxification and metabolism. It also helps the body absorb important minerals, such as zinc and selenium.5
- Tryptophan is a precursor to neurotransmitters that help regulate appetite, sleep and mood.6
- Leucine is another branched-chain amino acid that is needed for muscle growth, blood sugar regulation and wound healing.7
- Isoleucine is also a branched-chain amino acid involved stimulating muscle metabolism, immune function and energy.8
- Histidine is needed for the production of histamine which is important for sleep, digestion and immune function.9
- Lysine helps make hormones, absorb calcium and maintain a healthy immune function.10
- Cysteine is one of the three components needed by the body to synthesize glutathione – the body’s major antioxidant.11
As you can see, these amino acids are extremely important building blocks with lots of different functions in the body.
Amino Acids in Whey Protein
There are many different options for protein powders on the market, but the amino acid content in them can vary significantly. Whey protein, made from milk, is one of the best absorbed sources of amino acids that also has a complete amino acid profile. The amino acids in whey protein include all of the essential amino acids and most of the non-essentials as well.
The amino acids in whey protein make it a nutrient-dense source of protein. It is great for those who feel like they may not be adequately meeting their protein needs, who have higher needs than most, or for those who just want to be sure they are taking a high quality protein. Whey has been found to improve exercise performance, help maintain muscle mass, promote weight loss, and enhance immune function.12 It is truly the optimal protein in terms of nutrition and amino acid composition.
Choosing a Protein Powder
When you are choosing a protein powder, even a whey supplement, you want to be sure to choose a product that is the least processed. The amino acids in whey protein and other proteins are very sensitive to heat. When exposed to heat during processing, the proteins can start to break down or become denatured. This decreases their effectiveness and damages many immune-boosting proteins and nutrients.
The source of the whey also matters. Whey is made from the liquid leftover from making cheese. The type of milk it is sourced from matters for the nutrition and fat composition as well.
There is a lot to think about when choosing a protein powder, but always consider quality first to help support your health, muscles, and immune system.