All amino acids consist of a specific recipe of nitrogen, carbon, oxygen, and hydrogen. They differ only by a ‘side chain’ in addition to these main ingredients. Although the theoretical number of aminos that could exist is just about infinite, there are only 20 that are bodies need to work and grow like it supposed to. However, your body can produce enough of 11 of these from the 9 that are classified as ‘essential.’1 In short, you can’t make these 9 from anything else; they must come from your diet.
Chains of amino acids are what constitutes protein. Since animal protein is far more like human protein than any plant protein, it is the best source. When you consume protein (from an animal or plant), your digestive system breaks it down into individual amino acids that it then absorbs into your bloodstrem. Once absorbed, your body rearranges those amino acids into proteins that it needs. Your body manufactures thousands of different proteins from amino acids and have various functions such as muscle growth and immune function.2
Conditionally essential amino acids
The truth is, some amino acids, while ‘non-essential,’ can become essential under the right circumstances. For instance, arginine is non-essential, but your body just can’t produce enough of it when you have certain diseases like cancer.3 Also, if you are very athletic, especially a weightlifter, you need far more glutamine than average folks that aren’t, if you want to recover adequately. Thus, it is important to utilize supplements for any amino acids that you might need in your diet for specific reasons.
The Essential Amino Acids
Here are some functions of the essential amino acids (and why you need them in your diet):
Phenylalanine
This is precursor for several neurotransmitters; the chemicals that allow your brain cells to communicate properly. It is also important in the production of other amino acids (non-essential ones of course).4
Valine
Along with leucine and iso-leucine, this is one of the branched-chain aminos. These 3 aminos together are best amino acids for muscle growth. Valine is particularly important in building muscle of course, but also energy production.5
Threonine
The main structural proteins in your skin and connective tissues are highly dependent on threonine. This is important because these tissues represent an enormous amount of ‘you.’ It is also important for breaking down fat and immune function.6
Tryptophan
Many people think tryptophan makes you feel tired (mostly from turkey on Thanksgiving) but that’s actually a myth. 5-Hydroxy-tryptophan does make you tired however, and you clearly need tryptophan to make it. It is also important for maintaining the right amount of nitrogen in your body. Like phenylalanine, it is essential in the production of important neurotransmitters (like 5-Hydroxy-tryptophan).
Methionine
This amino is particularly important in metabolism and detoxifying your cells. The various tissues of your body are also unable to grow without it and it helps them absorb vital minerals.8
Leucine
This is another branched-chain amino, so it is clearly important for muscle growth and health. In addition, it helps regulate blood sugar and helps your body to heal wounds and produce growth hormones.
Isoleucine
The last of the branched chains, this one is heavily concentrated in muscle tissues and plays an important role in the creation of muscle. It is also important for immune function, production of hemoglobin (essential in blood to carry oxygen) and regulation of energy.10
Lysine
Although not a branched chain amino, this one is also important in protein synthesis and the production of various enzymes. It also helps you absorb calcium to keep your bones strong. Lysine is also important in the production of energy, collagen, and elastin.11
Histidine
You may be familiar with histamines, those sometimes-annoying chemicals that are responsible for allergic reactions. They are made from histidine (hence the similar names). But histamines do more than make you sneeze. They are also involved in digestion, sexual function and sleeping. It is also essential to the integrity of myelin sheaths. These are the essential ‘covering’ over all brain cells.12
The Importance of Amino Acids
Many times, people think of protein, and thus amino acids, as essential for muscle growth and that’s about it. But they are far more important than that. Consider that 80% of your dry (waterless) bodyweight is protein (which consists of amino acids). Pretty much every part of your body and every chemical that is essential to life is made mostly of protein. Thus, it is important to get an adequate amount of protein every day to ensure that your body can function at its best.
