Threonine is one of the 20 "normal" amino acids. While you might have heard that you can take threonine supplements as a treatment for anxiety, there's no scientific proof to back this up. You need threonine to maintain normal body function --- it's an essential amino acid --- but it won't benefit you psychologically.
Amino Acids
Amino acids are the building blocks of protein. You obtain them when you consume protein-containing foods --- the digestive enzymes in your gut break the proteins down into their amino acid constituents, which you absorb into the bloodstream. You use amino acids for a number of purposes: you can burn them for energy, use them to make other small molecules, and use them as building blocks for your own proteins, explains Dr. Gary Thibodeau in his book "Anatomy and Physiology."
Threonine
Threonine is one of the amino acids. Like all amino acids, its structure consists of a central, or "alpha," carbon to which a hydrogen atom, a COOH group and an NH2 group are attached. Amino acids also have a fourth group attached to the alpha carbon, but it varies depending on the type of amino acid. In the case of threonine, the variable group --- called a side chain --- has the formula CH(OH)CH3, note Drs. Reginald Garrett and Charles Grisham in their book "Biochemistry."
Depression and Threonine
There are many causes of depression; some are due to external events, such as tragedies, while others are due to aberrant brain chemistry. Scientists continue to learn more about chemical depression, but so far, it appears that low levels of serotonin and dopamine --- both neurotransmitters --- can contribute. Depression treatments attempt to regulate concentrations of key brain chemicals. There is no evidence, however, that threonine plays any role in regulating brain chemistry or elevating mood.
Alternatives
While threonine doesn't appear to elevate mood, another amino acid --- tryptophan --- might. Tryptophan is turned into serotonin by the body, and serotonin helps promote relaxation. If you're depressed, however, it's best to see a doctor or therapist rather than trying to treat your own symptoms using tryptophan, due to the complex nature of brain chemistry and the potentially serious nature of depression.
References
- "Anatomy and Physiology"; Gary Thibodeau, Ph.D.; 2007
- "Human Physiology"; Lauralee Sherwood, Ph.D.; 2004
- "Biochemistry"; Reginald Garrett, Ph.D. and Charles Grisham, Ph.D.; 2007
