The Serotonin Connection with PMS

Medical research has linked all the major symptoms of PMS with low serotonin. Symptoms triggered by low serotonin include:

Numerous research studies have shown that serotonin levels decrease when tryptophan is depleted. The studies have found that many patients with PMS symptoms improve when the level of tryptophan is raised.

. Low serotonin is linked to PMS symptoms

At the Royal Edinburgh Hospital in Scotland , a review of the medical literature stated, "Evidence is presented that the mood changes which commonly occur premenstrually are linked to cycle-related alterations in [serotonin] activity in the central nervous system, and premenstrual food craving may be a marker of such alterations."

J Bancroft. "The menstrual cycle and the well being of women." Social Science & Medicine. September 1995; Vol 41, No 6: pages 785-791.

From the University of Leeds in the UK , a review of the research on PMS looked at issues of appetite and eating behavior. They reported, "Fluctuations in appetite, cravings and energy intake during the menstrual cycle may occur in parallel with cyclical rhythms in serotonin, which can be accompanied by affective [mood] symptoms. The premenstrual phase can be considered as a time when women are especially vulnerable to over-consumption, food craving and depression. This is often associated with low serotonin activity."

L Dye and JE Blundell. " Menstrual cycle and appetite control: implications for weight regulation." Human Reproduction ( Oxford , England ) . June 1997; Vol 12, No 6: pages 1142-1151.

Another review of the literature summarizes conditions associated with low serotonin, concluding: "serotonin levels have been implicated in the regulation of sleep, depression, anxiety, aggression, appetite, temperature, sexual behavior and pain sensation." [These are the same conditions that typical occur in PMS.]

TC Birdsall. " 5-Hydroxytryptophan: a clinically-effective serotonin precursor." Alternative Medicine Review . August 1998; Vol 3, No 4: pages 271-280

At the psychiatric unit at Albert Chenevier Hospital in Creteil , France , researchers reviewed the scientific literature on a severe form of PMS - premenstrual dysphoric disorder. They reported: "The most widely studied and frequently blamed hypothesis regarding premenstrual dysphoric disorder is serotonin dysregulation. Serotonin is particularly involved in expression of irritability and anger, but also in occurrence of depressive symptoms and specific food cravings, precisely found in the premenstrual dysphoric disorder."

F Limosin. "Psychiatric and psychological aspects of premenstrual syndrome." L'Encephale . November-December 2001; Vol 27m, No 6: pages 501-508

. Both low serotonin and low tryptophan have been implicated in PMS

At the University of Otago in New Zealand , a study of tryptophan depletion was used to lower serotonin in 16 women with documented premenstrual syndrome. Researchers reported, "Tryptophan depletion caused a significant aggravation of premenstrual symptoms, particularly irritability. Symptom magnitude was correlated with the degree of depletion of tryptophan. This result supports other evidence implicating serotonin in premenstrual syndrome."

DB Menkes and others. "Acute tryptophan depletion aggravates premenstrual syndrome." Journal of Affective Disorders . September 1994; Vol 32, No 1: pages 37-44.

A study at the Institute of Psychiatry , Kings College of London evaluated the effects of tryptophan depletion on healthy women. The results: "Women who had received the tryptophan depletion drink showed more behavioral aggression in response to provocation. The conclusion: Decreased serotonergic [serotonin] neurotransmission increases aggression in women as well as men."

AJ Bond and others. "Tryptophan depletion increases aggression in women during the premenstrual phase." Psychopharmacology . August 2001; Vol 156, No 4: pages 477-480.

. Tryptophan has been found to reduce PMS symptoms

A study at the Department of Psychiatry, St. Mary's Hospital, Montreal , tested the efficacy of L-tryptophan, which acts specifically on the serotonin pathway. This particular study was a randomized, controlled clinical trial, which is considered the gold standard of good research. In the evaluation, 71 women with premenstrual dysphoric disorder were treated with L-tryptophan or with a placebo (a sham treatment). The tryptophan was given monthly from the time of ovulation to the third day of menstruation, for three consecutive months. The evaluation "revealed a significant therapeutic effect of L-tryptophan relative to placebo for the cluster of mood symptoms.mood swings, tension, and irritability.These results suggest that increasing serotonin synthesis has a beneficial effect in patients with premenstrual dysphoric disorder."

S Steinberg and others. "A placebo-controlled study of the effects of L-tryptophan in patients with premenstrual dysphoria." Advances in Experimental Medicine and Biology. 1999; Vol 467: pages 85-88.