Mast cells live in connective tissue all over our bodies, particularly the skin, gut, mouth, nose, lungs and brain. They are part of our immune system and necessary for our survival. We all have mast cells and they do an important job of protecting our bodies from harmful outside ‘invaders’ like germs and parasites. However, for reasons as yet unknown, mast cells can go haywire and react to things which they should consider ‘safe’ and just ignore. When this happens, the mast cells kind’ve explode and release over 30 chemicals (known as mediators) into the bloodstream. This explosion is known as de-granulation.
Mast cell mediators are grouped into 9 categories:
- Biogenic amines: histamine and serotonin.
- Enzymes: tryptase, chymase, carboxypeptidase A, peroxidase, B-hexoaminidase, phospholipases, matrix metalloproteinases.
- Proteoglycans: heparin and chondroitin sulphate.
- Chemokines: IL-8, MCP-1, MCP-3, MCP-4, RANTES, Eotaxin.
- Polypeptides: renin, substance P, corticotropin-releasing hormone (aka CRH), urocortin, vasoactive intestinal polypeptide (aka VIP), angiogenin.
- Phospholipid metabolites: leukotrienes B4 and C4, prostaglandins D2 and E4, platelet activating factor.
- Cytokines: interleukin 1,3,4,5,6,8,9,10,12,13,14,16,18 & 25, macrophage inflammatory protein, monocyte chemoattractant protein, interferon a, β & ƴ, tumor necrosis factor, leptin.
- Growth factors: stem cell factor, granulocyte monocytecolony stimulatory factor, vascular endothelial growth factor, fibroblast growth factor, nerve growth factor, platelet derived growth factor.
- Nitric Oxide.
As you can see above, the biogenic amines Serotonin and Histamine are mast cell mediators and released when mast cells explode (de-granulate). And although the other endogenous biogenic amines such as adrenaline and dopamine aren’t released by mast cells they are affected by mast cell activation.
A list of symptoms caused by mast cell activation can be found here.
Diet and Mast Cell Disease
Eating high histamine foods has zero effect on our mast cells, shocker I know! There is absolutely no evidence that any food liberates the histamine stored in mast cells – see this page for details. While some people react to specific foods it’s not because the food contains too much histamine. We don’t know why my mast cells react to apples and yours don’t, or why your mast cells react to lentils and mine don’t, but it’s not related to the foods’ histamine content.
Why, then, should those with mast cell disease follow a low histamine diet? Because it theoretically should help symptoms. Your faulty mast cells are producing huge amounts of histamine – too much for your body to be able to deal with. What you don’t then need is to eat foods which also contain large amounts of histamine to add to the situation. Reducing exogenous (ingested) histamine will place less burden on the body so that it can concentrate on dealing with the endogenous (internal) histamine.
Bear in mind, however, that when mast cells de-granulate histamine is only one of many mediators which are released and eating a low histamine diet will have no impact on symptoms caused by these other mediators, many of which cause inflammation which is why some people with mast cell disease follow both a low histamine and an anti-inflammatory diet despite the evidence for anti-inflammatory diets being about as speculative as the evidence for low histamine diets!
Is it Curable?
In a word no, and it’s certainly not curable by diet. Symptom management is the best you can hope for and even then it’s tricky. Faulty mast cells can de-granulate for any number of reasons: menstrual cycle/puberty/menopause; exercise; stress; high emotions (good or bad); if you get a virus; being too hot or too cold; barometric pressure; exposure to chemicals like perfume or bleach; and 100 other things, so unless you can control all those managing symptoms is problematic. I tell it like it is, and that’s the reality of mast cell disease.
For more information on the role of a low histamine diet in HIT and MCD by Dr Joneja click here http://www.foodsmatter.com/allergy_intolerance/histamine/articles/histamine-mastocytosis-joneja-05-15.html
There is also slightly more information on MCAD on my Guide To Mast Cell Disease page.