According to the National Institute of Health, bright light therapy, psychotherapy, exercise and the consumption of tryptophan-rich foods increase serotonin levels in the human brain. Increasing serotonin levels in the brain helps to quell the effects of mood disorders associated with depression, such as major depressive disorder, seasonal affective disorder, dysthymia, premenstrual dysphoric disorder and the depressive phases of bipolar disorder.
Alex Korb, Ph.D. lists two more possible methods of increasing serotonin levels in the brain: getting a massage and remembering happy thoughts. The idea of increasing serotonin levels in the brain is one of the ways to treat the unhappiness or depression associated with serotonin malfunction within the brain; however, it is not the only method regarding the alteration of serotonin activity.
Serotonin systems can malfunction for other reasons besides just low levels, explains Alex Korb, Ph.D. A person may not have enough serotonin receptors in her brain or neurons may be absorbing serotonin too rapidly as well. Selective serotonin reuptake inhibitors alter serotonin activity in a different way: they block neurons' absorption of serotonin, leaving it free within the synapses and able to induce positive moods. Selective serotonin reuptake inhibitors do not affect the overall level of serotonin in the brain, they simply change what happens to it. In combination with increasing levels of serotonin using the aforementioned methods, selective serotonin reuptake inhibitors may be the best option for using serotonin levels more efficiently within the brain.