Brain allergies – do they exist?

Allergies are a common condition experienced by a large percentage of the Canadian population.


Dominique Vanier
Dominique Vanier

24 August 2016

But what about an allergy occurring in the brain?

A small, somewhat controversial body of literature defines a brain allergy as any abnormal reaction to a food or other substance that creates psychological, emotional, or neurological symptoms.

Indeed, allergic symptoms can go beyond their bothersome impacts on the sinuses or the digestive tract. There are a multitude of emotional and behavioural symptoms that can occur alongside an allergic reaction, such as anxiety, agitation, confusion, depression, palpitations, sweating, as well as lack of concentration and mental slowness – or, what is otherwise known as “brain fog.”

For instance, newer research is suggesting there is in fact a link between brain fog (or brain allergies) and impairments in digestive function. An overwhelming number of patients suffering from either irritable bowel syndrome (IBS) or small intestinal bacterial overgrowth (SIBO), for example, will agree that they experience cognitive changes upon ingesting offending foods.

One mechanism by which the brain experiences adverse symptoms during a food allergy or other abnormal digestive processes may be due to a small molecule called zonulin.

When zonulin levels are increased, it has the ability to open up the spaces between the cells of the intestinal lining, causing “leaky gut” and resulting in increased gut permeability as well as a host of alarm bells in the immune system.

Zonulin, surprisingly, can also impact the permeability of the blood-brain-barrier, which is a protective structure in the brain that prevents the passage of certain harmful substances.

Increased permeability of the blood-brain-barrier could lead to “leaky brain,” resulting in symptoms that are characteristic of a brain allergy, such as brain fog, reduced concentration, and inflammation.

The Hippocrates saying, “all disease begins in the gut” still holds much merit today. Addressing a brain allergy should begin by examining digestive function, nutrient absorption and assimilation, and the involvement of the immune system during the digestive process.

The following natural approaches can be taken to help reduce unpleasant cognitive effects associated with leaky gut and allergies:

  • Avoid food triggers and allergens. If the inflammation causing cognitive difficulties is starting in the gut, be sure to determine and then avoid food triggers. Those who suffer from IBS and SIBO often find relief when eating a low FODMAP diet. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols, which are carbohydrates that easily ferment and cause gas and bloating in individuals who have susceptible digestive tracts.
  • Drink molkosanMolkosan is a prebiotic drink rich in L+-lactic acid, which is known to support the growth of healthy gut bacteria and improve digestion and gut inflammation.
  • Multiple animal studies support that exercise alters gut microbes, which promotes brain health. Other studies performed in athletes suggest that exercise may promote bacterial diversification in the gut, positively impacting digestion.
  • Rebuild the gut lining. L-glutamine is a major fuel source for colonocytes (the cells that make up the digestive tract). Taking L-glutamine in powdered form daily may help decrease intestinal permeability and optimize digestive function.
  • Decrease histamine levels. If the brain allergy is caused by a true allergy-mediated immune reaction, high histamine levels will play a role in allergic symptoms. Allergy relief is an effective remedy that can reduce histamine and relieve symptoms such as itchy nose, watery eyes, and scratchy throat.