Those of us who experience this, I believe, are like canaries in a coalmine. Living with severe histamine intolerance and complex allergic conditions means many experience diverse systemic effects that often go unrecognised. This includes complex cognitive difficulties like obsessive thoughts, anxiety, and many more that are often simply attributed - even diagnosed as mental health issues.

I have had chronic severe allergies since I was an infant, male 55, and have literally only just discovered that there are four specific classifications. These are IgE-mediated, Non-IgE-mediated, Mixed-Type reactions and Non-Allergic reactions (which in my case includes lacking the DAO and lactase enzymes). I have been having severe reactions to histamine for the past 10 years and less severe reactions prior. I put it down to age and something unknown and so began the mission to try and determine what it was.

This took 7+ years and the profound revelation (that I figured out myself) was that my symptoms were exacerbated pretty much directly after a massive yeast overload. I had made doughnuts and didn't realise they weren't fully cooked and ate about four.

I was so sick the next day and literally felt like I had been poisoned - like I had become a living, breathing yeast factory (it is sort of funny - but it isn't). It was only just over two years ago that I made the connection that this was precisely when it all started - chronic diarrhoea, hives (with a single persistent one on the back of my neck for years), cognitive decline and many other more serious symptoms began.

After finally figuring out it was yeast, and eliminating that from my diet (not easy, yeast/yeast extract is in so many things), the hive went away and the other symptoms improved. If I accidentally consumed yeast, the hive and everything else would return for weeks.

Following the yeast incident, I developed persistent thoughts of being poisoned - whether through external sources, self-administration, or exposure to unavoidable environmental triggers. This was difficult to understand and deeply unsettling. The thing is, I was being poisoned.

This psychological phenomenon is a clinically plausible and under-investigated response to physiological threats, in my case primarily fungal exposures (yeast and mould) and associated non-immune-mediated intolerances. Clinical evidence supports the view that such cognitive manifestations frequently arise as psychological responses to genuine biological stressors, reflecting the mind's attempt to rationalise ongoing somatic distress.

This raises a clinically significant question: how many individuals have received primary psychiatric diagnoses when their presentations actually reflected psychological responses to unidentified physiological insults? The potential for diagnostic error - where psychological symptoms mask underlying physical causes warrants greater clinical consideration, particularly in cases involving environmental sensitivities, food intolerances, or chronic inflammatory conditions that may manifest with prominent psychological features before their physiological basis is recognised.

I mention this because there may have been a triggering event for you or someone you know as well - a medical intervention, an allergen overload, an infection, something that catalysed a systemic overdrive like mine did. For me, recognising that event was crucial, even though I'll never be able to prove that it caused everything that followed. The timeline is the evidence: my symptoms appeared directly after that exposure, and whilst that's not the kind of proof that satisfies medical science, it's valid and essential knowledge about one's own body. Whatever it was, identifying a connection, that recognition matters - both for understanding this condition and an explanation for why everything felt so crazy.

Even though for me, it was not a complete solution, it provided an answer to why I was having many of those symptoms, which in itself was a huge revelation. As often mentioned by others who experience all of this, it is as much about understanding the why as it is about fixing it. Spending years trying to work out "is it this, is it that?" etc. is so profoundly exhausting and psychologically taxing. Combine that with the physiological effects of dietary and/or external triggers and it's a double whammy.

With diagnoses back in the 70s/80s, you were pretty much allergic or not allergic. That was my experience. I was never told about these other mechanisms that have clearly played as big a part. We do know more now, but so much is still completely unknown.

Heeding the Warning Signs

What affects us acutely and severely today may well be affecting countless others more subtly - people who haven't yet connected their brain fog, fatigue, digestive issues or mood changes to what they're eating or breathing. We are the early indicators of systemic problems: gaps in medical education, outdated diagnostic frameworks that haven't kept pace with emerging science, and perhaps even environmental or dietary shifts that our bodies simply weren't designed to handle.

The fact that it took me 50+ years to learn about non-IgE-mediated reactions and enzyme deficiencies - despite a lifetime of severe symptoms - speaks volumes about how much is still unknown, or worse, how much we know but fail to communicate. If we are the canaries, then the question becomes: is anyone listening? Our experiences, our self-discovered connections, our years of exhausting detective work - these aren't just personal struggles; they are data points, warning signs, calls for systemic change in how we approach, diagnose and validate these complex conditions.

Just as those small birds served as early warning systems for miners, detecting toxic gases before they became lethal to humans, those of us living with severe histamine intolerance and complex allergic conditions may be signalling something far broader about our modern environment and medical understanding.

Perhaps some of the most attuned canaries developed a way to signal danger early enough so that no one had to die - not the miners, and not themselves. I have sometimes wondered whether any of the miners were sad if their canary died. I am sure the sensitive ones were. All of them grateful, of course.

Perhaps some of the most attuned canaries developed a way to signal danger early enough so that no one had to die - not the miners, and not themselves. I have sometimes wondered whether any of the miners were sad if their canary died. I am sure the sensitive ones were. All of them grateful, of course.