Probiotics are important in maintaining our gut flora, but they can still cause issues just like any supplement and most issues with supplementation go unreported on the natural health blogosphere. Everyone writes about the pros of taking probiotics, but what are the cons? The cons of taking probiotics is the topic of this upcoming blog series. The following blog entry is going to tackle histamine and probiotics.

Histamine is an organic compound produced by the body. The compound is produced during immune responses and as a neurotransmitter down regulator. Histamine produced by the stomach and the intestines help to regulate their function. There are four types of histamine receptors in the body, and activating each receptor performs a different task.1 2 3

  • H1 – blood vessel dilation, smooth muscle contraction of the bronchi and GI tract, stimulation of vagus nerve, increases histamine and arachidonic acid release, decreased AV node conduction of the heart, helps form nitric oxide, improves eosinophil function.
  • H2 – stimulates nasal and intestinal mucosa, relaxes the LES, increases vascular permeability, stimulation of suppressor T cells, increases stomach acid production, reduces neutrophil and basophil function, increases lymphocytes, increases activity of NK cells.
  • H3 – increases histamine in the brain as a neurotransmitter, suppresses norepinephrine release at parasympathetic nerve endings, stimulates nasal mucus, reduces bronchoconstriction and gastric acid.
  • H4  – enhances the function of eosinophils, mast cells, and neutrophils.

As you can see different receptors have differing effects on our digestive health, which is why it is important for its production and activation and deactivation of certain receptors to be in balance.

Most people make the compound out to be a monster. Too much histamine is the cause of my seasonal allergies. Overproduction is the only cause of my anaphylactic reaction when I eat shrimp, which I am allergic. Excess production is the reason I have heartburn, so I take a H2 antagonist like Pepcid to relieve my digestive woes. The main problem is not directly the histamine in all of these individual issues; the real problem is why too much is released or is circulating throughout the body during these health issues.4

The body needs the correct balance of the compound so that your digestive system, immune system, neurotransmitter system, cardiovascular system, and nervous system work properly.

Proper ingestion of omega 3 fatty acids (fresh fish only),5 extra virgin olive oil (as long as you are not sensitive to salicylates), vitamin B6,6 magnesium,7 and vitamin C8 can help the body maintain proper histamine balance. Some people also require taking mast cell stabilizers like quercetin (use with caution if you have a COMT mutation), or cromoglicic acid to help improve histamine intolerance symptoms. If you are suffering from having a histamine imbalance, you should try a histamine reduced diet to see if your issues improve. Proper sunlight exposure and vitamin D production may help with histamine intolerance as well. Finally, some people supplement directly with the DAO enzyme which breaks down histamine in the body with differing success.

If you are supplementing probiotics and have histamine issues, you should only supplement histamine-degrading probiotics instead of histamine-producing probiotics until the imbalance corrects itself. The intestines and stomach for proper function require histamine. It is unknown if these probiotics increase levels in vivo in humans, I would still limit them if needed. Histamine-producing probiotics should not be used until the body can maintain proper levels of the compound.

Histamine Producing (L-histidine to histamine)/Modulating/Degrading Microorganisms

Histamine Immune Modulators/Producers:9 10 11 12 13 14 15

  • Candida
  • Bacillus coagulans SL5
  • Bacillus licheniformis A7
  • Bacillus subtilis
  • Citrobacter
  • Clostridium perfringens
  • Escherichia coli
  • Enterobacter
  • Enterococcus faecalis
  • Helicobacter pylori
  • Hafnia alvei
  • Klebsiella pneumoniae
  • Klebsiella oxytoca
  • Lactobacillus brevis
  • Lactobacillus bulgaricus
  • Lactobacillus casei
  • Lactobacillus reuteri
  • Morganella morganii
  • Proteus mirabilis
  • Staphylococcus aureus
  • Streptococcus thermophilus

Histamine Degraders/Neutral:16 17 18

  • Bacteroides fragilis
  • Bifidobacterium animalis ssp. lactis Bb12
  • Bifidobacterium infantis
  • Bifidobacterium longum
  • Lactobacillus casei 4a and 4b
  • Lactobacillus gasseri
  • Lactobacillus rhamnosus
  • Lactobacillus plantarum
  • Lactobacillus salivarius

Probiotic Supplements Without Histamine Producing Bacteria:

  9. Preedy, Victor. Processing and Impact on Active Components in Food, Academic Press, 2014.