In recent times there has been a huge increase in awareness of how important gut health is, and when it comes to skin – gut health is everything. And with this increase in awareness there has been a subsequent rise in consumption of fermented foods like sauerkraut, kim chi, kefir, kombucha and yoghurt.

Fermented foods are a great, whole food source of probiotic bacteria and, in turn, their benefits to our insides. But did you know they might be doing your skin more harm than good…?

Let me explain…

If your gut is already in pretty good nick, fermented foods will only add to the health and wellbeing of your microbiome – and this will be good for your skin.

However.

If your gut is compromised in any way, consuming fermented foods may make your skin worse.

This is because fermented foods are one of the biggest dietary sources of histamines. An intolerance to, an excess of, or issues with metabolism of histamine frequently can express itself on the surface of the skin through a number of symptoms, including but not limited to hives, eczema, rosacea and acne[1]. This is called histamine intolerance[2].

In one study[3] researchers found that a histamine-free diet improved a number of allergic conditions and, upon reintroducing histamine-containing foods there was a clearcut recurrence of eczema in half of the patients affected! No surprises then that a study found higher histamine levels aggravated eczema[4], and another[5] found that some atopic eczema patients had lower levels of a key enzyme that metabolises histamine – diamine oxidase.

In the case of acne I see patients who present with angry, red, itchy and inflamed breakouts that can flare up at times, and then the symptoms subside – seemingly without explanation.

Histamine Intolerance

To understand histamine intolerance we need to look at how our bodies metabolise it, which occurs in two ways:

• by an enzyme called diamine oxidase (called DAO for short) which is the main enzyme by which histamine metabolism occurs.
• by ring methylation by an enzyme called histamine-n-methlytransferase (called HNMT for short). Ironically, the activity of this enzyme is inhibited by high histamine levels!

Histamine intolerance occurs because there is either increased availability of histamine in the body and/or a reduction in the ability to clear out histamine from the body.

• Increased availability of histamine: this can occur because the body is producing an excess (in the case of allergies) or consumption of high histamine foods. Gastrointestinal bleeding can also see histamine rise.
• Reduction in the ability to clear out histamine from the body: a reduction in histamine degradation can be genetic or acquired.
  • From a genetic point of view, MTHFR polymorphisms will result in under-methylation and a subsequent accumulation of histamine.
  • An acquired impairment in histamine clearance may be a result of any number or possibly combination of the factors below:
    • any sort of gastrointestinal inflammation* (like leaky gut), disorder (like IBS) or disease (especially Crohn’s, Ulcerative colitis and allergic enteropathy) decreases the main enzyme (DAO – diamine oxidase) that clears histamine out of our bodies
    • biogenic amines (like adrenalin… hello stress!), alcohol or drugs can directly inhibit DAO activity
    • low levels of s-adenosyl-methionine (or SAMe) as this is a cofactor for HNMT
    • low levels of B6 and copper as they are cofactors of DAO (nutrients that are required for DAO to function)

* chronic skin disorders almost always have some degree of leaky gut and gut inflammation

Research shows that those who are sensitive to foods high in histamine may produce low levels of DAO. In addition, people with low levels of DAO typically have other digestive concerns too, such as increased intestinal permeability, SIBO (small intestinal bacterial overgrowth) and/or possibly other gut related symptoms and conditions.

High Histamine Foods

For a comprehensive list of high histamine foods, click on the image to download a copy. However, if it turns out to be the case that fermented foods are aggravating your skin, don’t bin them just yet. For the most part, any issues with histamine metabolism can usually be corrected once the cause has been identified:

• If you have intestinal inflammation, SIBO and/or leaky gut, a gastrointestinal repair program along with digestive support will see an improvement in DAO activity and therefore histamine tolerance.
• If you have a genetic polymorphism such as an issue with MTHFR, appropriate nutritional/methylation support should increase your tolerance to histamine.
• If stress is contributing to the issue, there are many options available with which you can address the impact on your mind, body and skin.
• If you are missing any key nutrients that are required for histamine metabolism a full nutritional assessment will pick this up (and identify if you’re missing anything else) and measures can be taken to correct the deficiencies.

The key here is to have a Functional Medicine Practitioner (like a Naturopath) do a thorough assessment and, if histamine intolerance is a problem for you, have a customised treatment program put together to address why you are having trouble with histamine.

What this means is, after treatment, you can slowly reintroduce fermented foods (one at a time), in small amounts, and test how you respond. In my experience, for most people, a 6 week treatment period is usually sufficient to restore appropriate histamine metabolism – with the exception of genetic polymorphisms which can require a bit more support.

If you’d like to discuss your skin issues with me you are most welcome to contact me here for a quick, no-cost and no obligation chat on the phone!

References:

1. Lugović-Mihić L, Seserko A, Duvancić T, et al. Histamine intolerance–possible dermatologic sequences. Acta Med Croatica. 2012;66(5):375-81.
2. Kovacova-Hanuskova E, Buday T, Gavliakova S, et al. Histamine, histamine intoxication and intolerance. Allergol Immunopathol (Madr). 2015;43(5):498-506.
3. Wantke F, Götz M, Jarisch R. The histamine-free diet. Hautarzt. 1993;44(8):512-6.
4. Worm M, Fiedler EM, Dölle S, et al. Exogenous histamine aggravates eczema in a subgroup of patients with atopic dermatitis. Acta Derm Venereol. 2009;89(1):52-6.
5. Maintz L, Benfadal S, Allam JP, et al. Evidence for a reduced histamine degradation capacity in a subgroup of patients with atopic eczema. J Allergy Clin Immunol. 2006;117(5):1106-12.