Allergies, seasonal allergies, “hay fever”, or in medical jargon, “allergic rhinitis” (AR) are all names for essentially the same thing. AR is extremely common affecting up to 25% of the Canadian population; and curiously, the incidence has been increasing over several decades.
Risk factors that may explain the increasing incidence of Allergic Rhinitis
– improved hygiene but reduced exposure to allergens early in life
– worsening air quality (ex. pollution from vehicular exhaust)
– toxicants such as phthalates, bisphenol A, pesticides, and endocrine-disrupting agents
Diet and Lifestyle
– increased time spent indoors (decreased exposure to outdoor allergens)
– decreased activity levels (decreased respiratory fitness)
– increased processed/refined food intake
– decreased fruit, vegetable, fiber, antioxidant and essential fatty acid intake
– early childhood antibiotic use
– decreased childhood bacterial/viral infection
– poor vitamin D status
– decreased breastfeeding
Allergic Rhinitis results from an abnormal immune reaction in the airways (primarily in the nasal passages) resulting in symptoms such as runny nose, congestion, sneezing, and itchy, watery eyes. These reactions occur in response to a variety of allergens, once the immune system has become sensitized. Examples of common allergens causing AR include pollen, grasses, weeds, pet dander, insect faces, and mold spores. AR can also worsen asthma symptoms (shortness of breath and wheezing) and increase the risk of other respiratory complications such as bronchitis, ear and sinus infections. In terms of quality of life reduction, AR can contribute to disturbed sleep patterns, fatigue, poor concentration, impaired performance, and low self-esteem. It carries a high economic burden once productivity, missed work days, and medical expenditures are factored in.
The most effective treatment for allergic rhinitis is to avoid the causative allergen, however this may be difficult or impractical in many cases. Identification of allergens can sometimes be done with testing, such as skin scratch testing or blood testing. Indoor air quality can be improved by minimizing dust, minimizing carpets/curtains, and using HEPA air purifiers in some cases. Humidity and water damage are other important factors as excess moisture can contribute to mold, mildew and dust mite growth.
Antihistamine medications are often used for symptomatic relief, along with nasal decongestants and corticosteroids. Although effective, some of these medications cause undesirable side effects which may explain why approximately 50% of allergy sufferers seek some form of natural therapy. Natural therapies are generally less effective for improving AR symptoms immediately, however there are several evidence-based therapies that can reduce the frequency and severity of AR.
Nasal/sinus irrigation with saline solution is a simple and reasonably effective way to reduce symptoms and medication use related to AR. There are a variety of options available at most pharmacies. Care should be taken to properly mix solutions and clean irrigation devices between use as per manufacturers directions.
Nutrition is a major factor in preventing allergic disease – even before we are born! Maternal diet and nutrition has a profound impact on the allergic tendencies of her offspring. High maternal intake of processed foods and vegetable oil increases risk of allergies in children. In contrast, the Mediterranean diet (a diet rich in vegetables, fruits, leafy greens, legumes, nuts, seeds fish, and essential fatty acids) shows the opposite effect. Breastfeeding children is associated with tolerance to allergens, and decreased allergic tendencies. Interestingly, allergic disease typically shows up early in life.
Poor dietary habits in both children and adults can promote inflammation and immune system dysfunction which may also play a role in allergic tendencies. However, high dietary intake of fruits, vegetables, fibre, essential fatty acids, and various antioxidants have all been linked to decreased risk of allergies. Food reactions can also contribute to AR, however this happens very infrequently in isolation. Food reactions are more often observed with other allergic symptoms such as asthma, eczema, hives, and gastrointestinal symptoms. Dysbiosis (defined as a lack of beneficial intestinal microbes such as Bifidobacterium and Lactobacillus species) also increases the risk of allergic disease; and various probiotic therapies have shown promise for reducing AR symptoms.
Vitamin D is crucial for maintaining a healthy immune system. Poor vitamin D status increases the risk of allergic disease like AR; and the majority of Canadians (especially those who do not supplement with daily vitamin D) have sub-optimal vitamin D levels. Supplementing with vitamin C, and the bioflavonoid quercetin can also help reduce histamine levels and improve symptoms. Butterbur (Petasites hybridus) root extract has also demonstrated similar effectiveness to antihistamine medication at reducing AR symptoms in several clinical trials.
Immunotherapy is a way of desensitizing the immune system by using very low doses of allergen formulas over a long period of time. There are several different therapies available, but most are given by injection in a doctor’s office, or sublingually (under the tongue) at home. Sublingual immunotherapy (SLIT) is growing in popularity due to its safety, effectiveness and the convenience of treatment. These therapies generally take several months to achieve their full effect but can produce great results.
~ Dr. Tim
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