1. Is there an underlying cause of histamine intolerance?
2. If someone has histamine intolerance, will they have to follow a low histamine diet forever, or can histamine intolerance be reversed?
3. If someone has seasonal pollen allergies and Oral Allergy Syndrome (reacting with mouth tingling and itching to apples, pears, cherries etc), are they very likely to have histamine intolerance?
In my opinion, much of histamine intolerance is driven by gut health. For example, a low FODMAP diet and gut repair with glutamine have been shown to cause as much as an 8-fold decrease in histamine. Probiotics may decrease histamine also. Environmental exposure can also contribute, seasonal allergens, toxins, molds…. One’s immune system, meaning how balanced is their immune system from early life development, also plays a large role, but also can’t be ‘treated.’
You can absolutely improve their histamine tolerance. They do not need to follow forever. Once they have been on the diet for at least a few weeks and after they have repaired their gut, then reintroduce to tolerance.
They are more likely to, yes. This indicates imbalance in the immune system.
When a client is on a low histamine diet, takes various anti-histamine medications, has worked on healing the gut, has tested negative for gut infections and SIBO, has had her genetics looked at and still cannot tolerate any amount of histamine containing foods, is it possible that this is the client’s “lot” for the rest of her life?
This is a tough one, Sandra, because I have found ‘healing the gut’ is often not handled great by many clinicians. For example, have you performed a therapeutic trial of antimicrobials, or the low FODMAP diet? How about fasting? Or an elemental diet? So checking that gut health is optimized would be worthwhile. Assuming gut health is optimized, in addition to everything else you listed, then this certainly suggests a more severe case of histamine intolerance. We have a podcast coming up that will provide a OTC antihistamine protocol to consider. Also, considering other interventions like LDN, helminth therapy, or even FMT might make sense for this person.
What do you think the root cause of her histamine intolerance is? Is it the SIBO?
Do you ever use glutamine to support epithelial integrity and repair?
Please see above regarding root cause. SIBO can absolutely be one. In some cases, I have used glutamine, after all other gut inventions have been performed (diet, probios, HAbx…). This does seem to help. One study did show glutamine could decrease histamine.
Make sure you verify a “hypothyroid” diagnosis.
Sadly, it is not an uncommon occurrence for someone to be incorrectly diagnosed as hypothyroid. This usually happens after a patient sees a well-intentioned but overzealous provider. We have discussed at length what the criterion for true hypothyroid are. We have also discussed what the criteria for SCH is. When a clinician fails to understand this, they can falsely label someone as hypothyroid who is not.
Why does this matter?
A diagnosis carries a psychological burden.
Being on thyroid Rx when you do not need to be can lead to fatigue and other reactions.
Treating a condition that someone does not have can lead to poor outcomes.
If you correctly identify this, your patients will be very grateful; it’s one less diagnosis and medication they need to take.
A short trial of thyroid HRT can be justified. In some cases, this may provide short-term relief whilst you fix the underlying cause of symptoms. However, it’s very important to clarify that you are using the hormone as a short-term aid and not because they have a diagnosed disease.
How do you determine if one is true hypothyroid? Simple, look at their TSH and free T4 from before they started using Rx. Or, said another way, look at the labs used to justify the Rx. If they don’t fit the criteria, they do not have hypothyroid. See the following for more, https://drruscio.com/subclinical-hypothyroid-dos-donts-episode-53/.
This is not to say the patient doesn’t have symptoms, but the cause of symptoms is likely not due to frank hypothyroidism and thus does not require Rx if they do not fit the criteria. This is more common than you might think, so be on the lookout.
I’d like to hear your thoughts or questions regarding any of the above information. Please leave comments or questions below – it might become our next Practitioner Question of the Month.
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