Serotonin and depression

Serotonin is a neurotransmitter i.e. it sends signals from one part of the brain to the other. This chemical plays a number of important roles in the body. It relaxes the body, promotes good appetite and sleep, improves sexual desire and function, enhances learning and memory capacity, and promotes good functioning of the cardiovascular system, endocrine system, muscles. Some studies have shown that the levels of serotonin are lower in people with depression. It is likely that the brain cells of people with depression produce lesser serotonin than that of normal people. It may also be that there are fewer serotonin receptor sites or that serotonin that is produced is not able to reach the receptor sites. A deficiency of the amino acid tryptophan can also result in serotonin deficiency since tryptophan is the precursor of serotonin. Some factors which can cause serotonin deficiency include poor diet, prolonged stress, exposure to toxic chemicals like insecticides, pesticides, substances like coffee, alcohol, nicotine. Most antidepressant medications aim to counter depression by boosting serotonin levels. Selective serotonin re-uptake inhibitors like citalopram, escitalopram, fluoxetine, paroxetine work in this manner. Nutrient therapy using 5 hydroxytryptophan and tryptophan can also help raise the levels of serotonin in the body.