Histamine is a component of foods — rather than an ingredient, per se — and histamine sensitivity is not an allergy, but as it can mimic an allergy, it’s often perceived to be one. Histamine is released in the body during a food allergic reaction, but if you consume it directly, you’ll experience similar symptoms, albeit never life-threatening. It is caused by an inability to metabolise and break down this excess histamine, often due to a deficiency of an enzyme called diamine oxidase (DAO), for which supplements are available.
In 2017, Dr Janice Joneja — probably the leading international expert on the condition — wrote The Beginner’s Guide to Histamine Intolerance, which I reviewed here. What interested me about the book was learning that diagnosis is not straightforward, and is essentially one of exclusion. There is no real test for histamine sensitivity — which may have something to do with the fact that a few (certainly not all) doctors, dietitians and immunologists still view the condition with a little scepticism and suspicion.
Thankfully, histamine intolerance research is continuing apace, and just recently a paper was published in The Journal of Pharmaceutical and Biomedical Analysis suggesting a new approach to the diagnosis of the condition, by determining levels of histamine and a related compound, methylhistamine, in urine — which would be less invasive than a blood test to investigate the activity of DAO.
Further, a paper published in the journal Allergy was also interesting: although it was small, a quarter of participants with suspected histamine intolerance had elevated histamine levels during the day, possibly due to reduced DAO levels, while the remaining three-quarters had normal histamine and DAO but increased prevalence of other food intolerances. Clearly, accurate diagnostic protocols are urgently needed.
This is clearly a fast moving field, now. When I wrote my first book in 2003, Living with Food Intolerance, I only dedicated a single page to the ‘amines’, with only a paragraph to histamine itself (which I didn’t even index, much to my shame). That book is in urgent need of an update, and I expect I’ll be needing to dedicate a whole chapter to it when I eventually get around to it!
Meanwhile, in a final piece of histamine news, healthcare professional readers may be interested to know that Dr Joneja has now brought out Histamine Intolerance: a Comprehensive Guide for Healthcare Professionals.
I imagine it is much needed …