A review of recent evidence suggests a link between diamine oxidase (DAO) deficiency and fibromyalgia. The review found that certain genetic variants associated with DAO deficiency were more common in people with fibromyalgia compared to the general population. Specifically, having more of these genetic variants was linked to increased symptom severity.
In some cases, taking DAO supplements showed a potential benefit. The review noted that people using DAO supplements experienced a larger decrease in pain catastrophizing and better scores on the Fibromyalgia Impact Questionnaire compared to those taking a placebo. This suggests that histamine intolerance, driven by a lack of the DAO enzyme, might play a role in how fibromyalgia affects certain individuals.
It is important to remember that this is a narrative review of emerging evidence rather than a single new clinical trial. While the findings are interesting, more large scale research is needed to confirm these links and determine how effective supplementation is for the broader fibromyalgia community. You should discuss any changes to your supplement routine with a healthcare professional.