Amino Acids are chemical units that are the basis or building blocks of all life on our planet.
Our bodies put together different combinations of these amino acids in long chains, linking them together with peptide bonds.   The particular combination of amino acids, in a particular pattern, determines what will be formed; proteins for creating hair, nails, organs, each type of muscle fiber, vital bodily fluids, etc.  Our bodies are continuously building these chains of proteins as required, as well as breaking down chains that are ingested, for use in building other chains.
Amino acids are utilized to facilitate many of the chemical processes that allow cells to function.  They are essential in the body’s ability to utilize and/or increase the effect of vitamins and minerals in our bodies.
In humans the liver is responsible for producing 80% of the amino acids it needs, the other 20% (known as essential amino acids) must be obtained from the diet.  The essential amino acids are Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, and Valine.  The other types of amino acids are referred to as non essential amino acids.  The term non essential only refers to the fact that we do not need to consume these in our diet, but are actually able to manufacture them.
I am always awed by the wisdom of our cells and our bodies.  Miraculously complex actions take place inside of us without any awareness on our part.
There are 28 commonly known amino acids that can be combined to synthesize the hundreds of proteins present in all living things.
The power of amino acid chain production is hampered by only one thing: The lack of a particular essential amino acid (or the body’s inability to absorb or create one).  If you do not have a properly balanced diet, one that supply’s enough of the essential amino acids, it will manifest as a physical disorder sooner or later.
This is why it is essential to have each and every amino acid present in meals.  If just one of the essential amino acids is missing from a diet, the body cannot continue to properly synthesize proteins.
Amino acids are considered one of the three basic nutrients for life.  It is their 16% nitrogen content that differentiates them from the other two basic nutrients, sugars and fatty acids.

I did say amino acids are essential for all life on our planet; take the herpes virus, which is responsible for genital herpes and cold sores, for example.  In order to thrive and replicate, this virus needs the amino acid Arginine.  Lysine, one of the essential amino acids, represses our body’s ability to metabolize Arginine, making life much more difficult for the herpes virus.  A diet high in Lysine can help to prevent and shorten the duration of herpes outbreaks.  A grain that is extremely high in Lysine is amaranth; check it out in our Gluten Free Grain of the Month for April.

http://www.herpes-coldsores.com/amino-acid-lysine-for-herpes.html

The branched chain amino acids Valine, Lsoleucine and Leucine as well as Tyrosine, Tryptophan, Phenylalanine and Histidine are able to provide energy directly into muscle tissue.  A deficiency of these in elderly people can produce depression or neurological problems.  Low levels of Tyrosine can lead to anemia.  People suffering from low levels of Methionine and Taurine (either from not enough in their diet or impaired metabolism), have a risk of developing allergies or autoimmune disorders, which is what Celiac Disease is considered.  Since the consumption of gluten for someone with Celiac Disease causes mal-absorption of nutrients through the small intestine (including essential amino acids), it is not surprising that some of the same symptoms of amino acid deficiency are present in people with this disorder: indigestion, depression, and even stunted growth.  Another amino acid L-Glutamine is used as a metabolic fuel for cells in the intestines; it helps maintain the villi and therefore the absorption surfaces of the gut.  Glutathione is necessary for repair of the intestines; if you cannot absorb enough of either of these…it sets a vicious cycle in motion.
There are other things that can cause a deficiency in a person’s amino acid levels besides an imbalanced diet or impaired absorption.  External factors such as trauma, stress, infection, age, drug use, overall health, as well as imbalances in other nutrients all affect our amino acid levels.

A word of warning here about supplements:  Take only with the advice of a doctor, nutritionist or dietician.  Certain supplements can be toxic in too high a dose; others need additional minerals to be utilized properly.  Balance is essential to health.  Balance is delicate, nutrition is complex, seek guidance!
For fast referencing on your own I recommend The Prescription for Nutritional Healing by Phyllis A. Balch, CNC and James F. Balch, MD.  A large book filled with vital nutritional information.
Getting complete nutrition from foods we eat remains the safest most balanced way to assimilate them.   In the natural world meats contain the most complete sets of amino acids. B What an animal’s body requires and utilizes in protein synthesis is not all that different from ours…so their amino acid content (in their veins, eyes, muscle, tissue, etc.) is very compatible with ours.   After ingesting meat, all the essential amino acids used in creating meat proteins, will be present in our bodies.
Keep in mind the old adage “too much of a good thing….” is infinitely applicable here; you do not want to eat too much meat, or take a lot of amino acid supplements!  Proteins are processed by the liver and their waste product by the kidneys; too much protein puts undue stress on these organs.

Grains and legumes are the next important source of amino acids, but because their formation is very different from ours, their amino acid chains, usually, do not contain everything that we need.
Pairing specific grains with specific legumes or beans was one way I handled this problem as a vegetarian.  An excellent cook book with lists of paired grains and legumes for complete amino acid availability is Laurel’s Kitchen by Laurel Robertson
This is an excellent book on nutrition, and eating responsibly for vegetarians.  It is not a Gluten Free book, but for nutritional information, it was the best source when I was studying nutrition in College and eating as a vegetarian.
Amaranth and Quinoa are more nutrient dense than other grains, having more available protein as well as minerals like calcium.  See the nutritional value comparison chart in Whole Grains  as well as read about Amaranth as April’s Gluten Free Grain of the Month.