Researchers from La Jolla Institute for Allergy in California have finally revealed for the first time in humans that mast cell release of histamine is a key trigger of eczema.
We have long understood that eczema is an immunological condition, whereby the skin becomes inflamed due to various triggers. When the body detects one or these triggers, inflammatory cytokines AND histamine are released as part of the immune systems attempt to deal with the threat. For some people, their ability to deal with this increase in histamine is compromised, leading to eczema.
What can trigger the release of histamine?
Gut bacteria – an overgrowth of unwanted bacteria in the gut such as Klebsiella or Citrobacter will release histamine. You may not have any gut issues at all, but the effect of this is seen on the skin with the development of eczema.
Inflammation – from infection, parasites, viruses and autoimmune conditions will stimulate the release of histamine from mast cells, which can cause eczema.
Oestrogen – unfortunately for women (and some men), oestrogen can stimulate the release of histamine. This is often the case in women with oestrogen dominance whereby they are unable to clear oestrogen effectivity through the liver. This is common in women with MTHFR and COMT gene mutations.
Stress – it is now known that stress releases cortisol releasing hormone (CRH) not only from the adrenal glands, but also on the skin. Therefore, CRH is stimulating mast cells to release histamine directly on the skin causing eczema.
High histamine foods – many foods increase histamine in the body including fermented foods (soy, miso, kimchi, sauerkraut), aged cheeses, alcohol, yeast, shellfish, canned tuna, processed meats, chocolate and tomatoes.
Mould – this is a big issue. If you have mould in your house this may be the major cause of your eczema. Mould is toxic to the immune system and will cause havoc with histamine. If you feel better when you are away from your home, this is a huge sign that you may have mould in your home hiding somewhere.
Why am I more susceptible to histamine and eczema than other people?
MTHFR gene mutation – people with MTHFR and methylation cycle issues can have issues breaking down histamine via the HNMT enzyme.
DAO gene mutation – the DAO enzyme is continuously released from the intestinal mucosa to help the gut get rid of excess histamine. A mutation in the gene leads to a reduction in functioning of this enzyme.
Chronic gut issues – those who have taken many rounds of antibiotics or reflux medication, have long standing IBS symptoms, and food intolerances will have lowered DAO activity in their gut.