Study, 1991
Do women with PMS have different tryptophan levels?
No. Women with PMS had similar tryptophan levels compared to women without PMS, both before and after ovulation. This suggests that low tryptophan is not the reason for PMS.
What they did
Researchers measured the ratio of tryptophan (an amino acid that affects serotonin and mood) to other amino acids in blood from women with PMS and women without PMS. They compared levels at different times in the menstrual cycle.
What they found
There were no clear differences between women with PMS and the control group, and no differences across different times of the cycle.
What it means for you
Some researchers thought low serotonin from low tryptophan might cause PMS, but this study suggests that is not the cause. Something else must explain the serotonin problems in PMS. The sample size is not stated in the abstract, which is a limitation.
5
competing amino acids measured alongside tryptophan
About the study
- Original title
- Tryptophan and neutral amino acids in premenstrual syndrome
- Authors
- Rapkin AJ, Reading AE, Woo S et al.
- Journal
- American journal of obstetrics and gynecology
- Year
- 1991
- Study design
- Study
- What was tested
- None - measurement study
- Read the paper
- doi.org/10.1016/0002-9378(91)90040-x