Blocked, runny or itchy nose, constant sneezing, itchy and watery eyes.. if you’re part of the 30% of people who suffer from allergies, you probably always wonder what really causes these unpleasant reactions. In this article, I’ll help you to find out a bit more about exactly what’s going on…
Article written by Ariane Monnami, nutritionist and micro-nutritionist.
Caused by pollen, this allergy is called seasonal rhinitis, otherwise know more commonly as hay fever.
Symptoms persist as long as the individual is exposed to the allergens which are present every year as flowers begin to bloom:
- Start of spring, tree pollen
- Throughout the month of July, grass pollen
- At the end of summer, common ragweed (Ambrosia artemisiifolia)
- During the spring snowmelt, mould
Persistant or perennial rhinitis
Some individuals can suffer from persistant rhinitis which is lasts throughout the year.
Persistant rhinitis is caused by allergic substances constantly present in the individual’s environment at home or at work: dust, mites, animals and mould. Individuals suffering from this can often appear to have a constant cold and symptoms can flair up several times throughout the day.
In other cases, individuals can also suffer from non-allergic vasomotor rhinitis. This occurs when there are variations in temperature or greater humidity, due to smoke, dust, strong odours, chemical products, as a reaction to medicine or hormonal changes.
The most common symptoms
Despite the misleading name ‘rhinitis’, allergic rhinitis can in fact affect the entire ENT area as well as the eyes:
- Itchy, runny nose
- Continuous sneezing
- Blocked nose
- Sinus discomfort
- Itchy throat, cough or rough voice
- Itchy roof of mouth
- Changes in sense of taste and smell, and hearing ability
- Fatigue, irritability, insomnia if symptoms last for several days over several weeks
These symptoms are caused by the immune system’s overreaction to substances called allergens:
- plant pollen
- animal/pet dander
When these substances come into contact with the eyes or airway of an allergic individual, the immune system can trigger an inflammatory reaction.
- Allergens enter the ENT mucosa
- They stick to the mast cells (immune cells) and trigger the release of histamine and other inflammatory molecules (leukotrienes, prostaglandins)
- Histamine causes allergic reactions (sneezing, itching) by stimulating specific receptors (H1 receptors) found on a variety of other cells.
- The other molecules cause local inflammation as well as an oedema responsible for congestion and discharge.
- Heredity plays an important role in allergy apparition. When two parents suffer from allergies, the likelihood for the child to suffer from allergic rhinitis is twice as high.
- Continuous/prolonged exposure to airborne allergens
- Exposure to cigarette smoke, especially during early years.
- Exposure to air pollution and other respiratory tract irritants (chimney smoke, air pollutants)
What areas are targeted by medicine?
It’s easier to understand which areas are targeted by medicine by looking at the table above:
- Antihistamines work by very specifically targeting histamine in the H1 receptors. They blockthe effects of histamine without actually stopping its release.
- Local or systemic cortisone acts on the inflammation and oedema.
- Vasoconstrictors work by preventing the oedema from forming.
Immunity defence works against all of these reactions: it prevents the allergen from sticking to the mast cell and therefore also prevents the release of different allergy mediators and inflammation.
Why are allergies becoming ever more common?
Several studies suggest that individuals who suffered from continuous respiratory tract infections in early years were less likely to suffer from allergic illnesses later on in life. This could suggest that the continuous improvement in hygiene conditions could contribute to the increase in allergy frequency.
Excess fatty acids such as omega 6 (sunflower oil, poultry skin) compared to omega 3 oils (fatty fish, colza oil, nut oil) encourages the production of prostaglandins and leukotrienes, pro-inflammatory molecules which increase allergic reactions.
According to Doctor Seignalet, allergic illnesses are linked to the “eliminatory system”
In effect, our bodies aren’t able to decompose some molecules found in our food and environment. These molecules must therefore be eliminated using a variety of emunctories:
- ENT mucosa
The last two emunctories mentioned above is where eliminating waste can cause several problems:
- Nasal hyper-secretion with initial nasal discharge and then in the throat.
- Trachea hyper-secretion causing a cough and increased expectoration.
When waste substances increase, chronic mucosa inflammation is caused by increased white blood cell intervention.
According to Doctor Seignalet, chronic mucosa inflammation would be the most important factor, allowing allergens to enter the body. This view also allows us to better understand the effect of probiotics on allergies as well as the importance of detox treatments which encourage waste elimination through the different emunctories.
- Dossier inserm https://www.inserm.fr/information-en-sante/dossiers-information/allergies
- Dr Jean Seignalet L’alimentation ou la 3ème médecine