How to deal with hay fever the natural way
Hay fever can be a real misery for sufferers. For some it can last from February to September every year (!). People suffering from hay fever experience symptoms such as repetitive sneezing, runny nose, teary eyes, headaches, drowsiness, earaches. Hay fever is not a fatal condition, but it does affect the quality of life of the sufferers for a few months. In America, it is the fifth leading chronic health condition, In this article, we will go over the basic physiology of how hay fever happens before exploring a few naturopathic practices, and herbal remedies to reduce the severity of symptoms.
WHAT IS HAYFEVER?
Hay fever is the common name for seasonal allergic rhinitis. The word “rhinitis” comes from the Greek “rhino” (= nose) and “-itis” (= inflammation) and refers to any medical condition in which the membranes of the nose are swollen and inflamed (the common cold, for example). In the case of hayfever, the cause of the rhinitis is an allergic reaction to air-borne particles (pollens).
What are pollens, and why do they trigger hay fever?
Put simply, pollen is the sperm of plants (see Figure 1). Pollens are the male cells of reproduction for flowering plants and conifers. And, much like in mammals, pollens have to travel to the eggs to fertilise them. To travel, pollens can use a variety of modes of transport: air (wind), water, animals (bees, birds, furry animals that rub their coats on plants). To increase the chances of landing on another flower, pollens have to be spread in large numbers (to increase their probability of reproductive success, which is the name of the game for all living things).
Figure 1: schematic representation of the anatomy of an archetypal flower, showing the male and female parts (pollen grains and ovules)
The first plants to kick off the pollen season are the Alder and the Hazel trees, which start to release their pollens in January (!). Elm and Willow start spreading their seeds in February, followed by Beech, Oak, Mimosa, Plane, Birch (which accounts for ¼ of all hay fever sufferers), and Ash in March. Grass and weed pollens (dandelion, plantain, nettle, daisies, mugwort) start getting abundant in the air from early May and stick around until September.
Pollens are microscopic structures (most of them are barely visible to the naked eye), whose shapes and sizes vary greatly between plants (see Figure 2). The outer surface of the pollen grains is made up of proteins and lipids for the most part. When the outer “coat” of the pollen grains is degraded, the proteins and enzymes contained inside are released. It is still up for debate which part(s) of the pollen trigger(s) the allergic cascade that leads to hay fever, the outside or the inside. The variations between plant pollens explain why some people get their hay fever earlier or later in the season (depending on which type of pollen they are sensitive to), but it also means that one person can be sensitive to a few different types of pollens and have a very long hay fever season as a consequence.
Figure 2: microphotograph showing the variety of pollen grain types (Radja et al., 2019)
How hay fever works
Hay fever happens in 2 phases (see Figure 3):
In the early phase, proteins found on the surface of pollen grains (antigens) are recognised by a certain kind of first line of defence antibodies, the immunoglobulins E (or IgE), found in the nose mucosa. These activated IgE are going to send a message to the mast cells (a type of unspecific immune cell) to start the degranulation process, which involves releasing histamines in the nasal mucosa. The release of histamine is responsible for local inflammation, widening of the blood vessels, mucus overproduction. All of these contribute to the feeling of ‘stuffiness’ in the sinus/ face area. This early phase of the allergic reaction happens within minutes of encountering the pollens and is characterised by sneezing, a runny nose, along with red, itchy and watering eyes.
The late phase of hay fever happens over a few hours after exposure to the pollen grains and involves a lot of different cells (basophils, neutrophils, eosinophils, lymphocytes) producing a lot of inflammatory substances (cytokines, prostaglandins, leukotrienes) that contribute to local oedema (swelling of the tissue) and tissue inflammation (in the sinuses and lungs), which leads to bronchoconstriction (tightening of the airways) and bronchial hyper-responsiveness (e.g. asthma). The inflammation of the tissue makes them more sensitive to allergens and more reactive (Bjermer et al., 2019). The systemic inflammation can then cause broader symptoms such as fatigue, malaise, sleepiness, difficulty concentrating, feeling ‘snappy’.
Figure 3: simplified schematic of the pathophysiology of seasonal allergic rhinitis (hay fever).
Who gets hay fever, and why?
It is estimated that about a quarter of the global population suffers from seasonal allergic rhinitis, that is 1 in 4 people. In the UK, about 20% of the population suffers from hay fever (1 in 5), and this number is expected to almost double by 2030. Seasonal allergic rhinitis typically develops during adolescence and early adulthood, but an increasing number of children above the age of 2 are affected. It also seems that the number of people who “grow out of it” in adulthood is decreasing. A number of factors have been suggested as risk factors for developing hay fever:
being born via C-section (Thavagnanam et al., 2008): A quarter of babies are now delivered via caesarean in the UK. Babies who do not emerge via the birth canal do not get inoculated with their mother’s beneficial bacteria and have a less varied microbiome as a result.
having fewer siblings (Penders et al., 2014): It seems that having more older siblings decreases the risk of developing allergies.
having limited exposure to domestic animals. Several studies have shown that the presence of pets in the house before birth and early in life is somewhat protective against allergies (Aichbhaumik et al., 2008).
urbanisation: Exposure to natural environments (farms, forests) in the first 3 years of life seems to confer some protection against allergic diseases (Campbell et al., 2015). About 80% of the UK population now lives in urban areas, and spend 90% of their time indoors.
excessive antibiotics use: a recent scientific review highlighted the impact of repeated courses of antibiotics during childhood on the risk of developing allergies later in life (S. Bloomfield, 2014).
overall poor microbiome diversity: multiple research groups have identified that a diverse microbiome (in the gut, on the skin, and in the airways) is somewhat protective against allergic diseases (S. F. Bloomfield et al., 2016).
genetic makeup: more than 25 genes have been identified as being implicated in the development of allergies (Portelli et al., 2015). Seasonal allergic rhinitis is part of a cluster of manifestations called atopic diseases, which also include asthma, and eczema (atopic dermatitis). A child with 2 atopic parents has 50% chance of being atopic. Atopic people tend to suffer from more than one atopic disease during their lifetime, often following a pattern called “the allergic march”. Typically, the atopic person starts by developing atopic dermatitis (eczema) in the first few months of life, some food sensitivities might also appear before the age of 12 months. This period is usually followed by hypersensitivity to indoor allergens such as dust or furry pets. In the first few years of life, respiratory tract infections will be accompanied with wheezing. Later on, the wheezing episodes will happen in between infections as well, developing into asthma. Finally, in late childhood, teenage years, or early adulthood, reactivity to outdoor allergens (pollens) start manifesting as allergic rhinitis (Thomsen, 2015).
Males and females are equally affected by hay fever, and ethnic backgrounds don’t seem to predispose to or protect from hay fever.
Can I get tested for hay fever?
When you go to the doctor with hay fever symptoms, your GP has the choice between two main types of tests:
the skin prick/scratch test (see Figure 4): this is an immediate hypersensitivity test during which the doctor or nurse places drops of different possible allergens (substances that trigger immune reactions) onto the skin and then uses a needle to scratch the skin to bring the allergen in contact with the mast cells from the epidermis and superficial dermis. If the individual has a sensitivity to the substance tested, a raised red spot will appear where the skin was pricked, usually within 15 to 20 minutes (early phase of the allergic reaction). This test gives a quick indication of what specific substances that person is allergic to (e.g. birch pollen vs nettle pollen) and to what degree they are allergic (depending on the speed and intensity of the skin response to the scratch test).
Skin scratch test for hay fever allergens.
blood tests: levels of specific IgE (immunoglobulins E, responsible for the initiation of the allergic reaction) can be measured in the blood using a fluorescence enzyme immunoassay (FEIA). The amount of IgE measured for one antigen is directly correlated with the level of sensitivity to this substance (e.g. birch pollen, dust mite, etc.). Results are sometimes not reliable, depending on the lab and on the antigen(s) tested, as some substances are well characterized and easy to measure, and others not so much. Total levels of circulating IgE can also be measured but are not really helpful in the case of allergic rhinitis as 50% of hay fever sufferers have normal levels of blood IgE. Same with total levels of eosinophils, this is not a specific measure but can help the GP establish a diagnostic of allergic rhinitis.
HAY FEVER TREATMENTS
Conventional treatments of hay fever
The most common treatment for the symptomatic relief of hay fever includes antihistamines and decongestants. Those drugs used in combination are quite effective in reducing sneezing and runny nose. Antihistamine eye drops help reduce itchy, watering eyes. The second-generation antihistamine medications do not have a sedative effect. Leukotriene receptor antagonists or cromolyn sodium sprays might be used if asthma is a presenting symptom of the hay fever. Those medications have very few side effects and are generally well tolerated.
When this first intervention is ineffective, doctors usually opt for corticosteroids nasal sprays and/or oral corticosteroids. Corticosteroid treatments must be titrated to the lowest dose possible. Prolonged use of this class of medication can have very detrimental side effects, such as adrenal suppression, adrenal crisis, anxiety, oral thrush, candidiasis, Cushing’s syndrome, depression, glaucoma, hyperglycaemia, reduced mineral bone density, sleep disturbances, irritability.
When these medications fail to alleviate symptoms of hay fever, immunotherapy might be considered. The principle of immunotherapy is to expose the body to increasing doses of the substance to which the patient is allergic sin order to induce a progressive de-sensitization of the immune system to this specific allergen. Immunotherapy by injections is effective in 80 to 90% of severe allergic rhinitis cases (Weber, 1997), however improvement in symptoms occur only after 6 to 12 months of treatment and treatment must be continued for 3 to 5 years (1 injection per week). Severe allergic reactions can occur during immunotherapy treatment, which must always be done under medical supervision. Sublingual immunotherapy is also available for a narrow range of allergies. The patients must start taking the daily tablets 3 to 4 months before hay fever season. Sufferers who adopt this treatment manage to reduce their hay fever medications by 50%. However, this is overall a less effective treatment than the injection immunotherapy.
Other measures that should be adopted when dealing with seasonal allergic rhinitis are include:
limiting exposure to allergens as much as possible: this means limiting going outdoors when the pollen count is high, especially during the months where your specific triggering pollens are active. Resources are available to get this information:
· https://www.metoffice.gov.uk/weather/warnings-and-advice/seasonal-advice/pollen-forecast
· My Pollen Forecast UK app
Also, keeping windows shut during pollen season will prevent allergens coming into your living environment.
showering and washing your hair every night. Pollens can stick to hair, so getting into the habit of washing it in the evening during hay fever season can make a significant difference on the exposure level. Alternatively, wearing a hat when outside can stop pollen from sticking to the hair. Wash the clothes that have been worn outside, again because pollen grains might stick to them and bring allergens into your house. Dry them indoors.
avoid petting or playing with furry animals that spend a lot of time outdoors during hay fever season as pollens stick to their coats. Give them regular baths.
wear sunglasses when pollen count is higher, to avoid irritation of the eyes from allergens.
Dandelion flower pollen
NATURAL REMEDIES FOR HAYFEVER
When supporting patients suffering from hay fever with a naturopathic approach, the treatment plan revolves around:
Dietary approach
A few weeks prior and during the duration of the pollen season, sufferers should try to increase their intake of fresh fruits and vegetables (frozen is a great option), omega-3 and decrease the amount of sugar, wheat products, dairy products, omega-6 and trans-fatty acids they consume. To help with reducing inflammation and thinning the mucus secretions, increasing the amount of liquid intake is recommended, with warm herbal teas, mineral water, vegetable juices, broths, and soups. A few nutrients have been shown to play key roles in the management of hay fever and are worth supplementing with a few weeks prior and during the hay fever period:
Zinc: this mineral is implicated in numerous physiological processes, including immune system function. It has potent antiviral properties and can reduce inflammation in the airways. It has also been shown that patients with low levels of zinc have higher IgE-mediated immune responses to allergens (Seo et al., 2017). The recommended daily dose for an adult is up to 30 mg.
Vitamin C and bioflavonoids: bioflavonoids are antioxidants that occur in all citrus fruits and make vitamin C more bioavailable. Vitamin C can help reduce the amount of histamine produced by white blood cells and reduce the histamine-driven bronchial inflammation that occurs in allergic rhinitis (Bucca et al., 1990). The recommended daily dose for an adult is 2 g of vitamin C and 1000 mg of mixed flavonoids and/or 500 mg of quercetin.
Vitamin D: hay fever sufferers seem to have lower levels of serum vitamin D compared to non-sufferers, and the severity of allergic symptoms correlates with the level of deficiency. Supplementing with vitamin D can significantly reduce nasal symptoms of allergic rhinitis after a month (Malik et al., 2015). The recommended daily dose of vitamin D for an adult is 1000 IU.
Vitamin E: vitamin E is a powerful fat-soluble antioxidant that is thought to reduce the allergic response by modulating mast cells degranulation. In one study, daily supplementation with vitamin E helped reducing the nasal symptoms of hay fever (Shahar et al., 2004). The recommended daily dose of vitamin E for an adult is up to 800 IU.
N-acetylcysteine: is a potent anti-inflammatory and antioxidant that has been shown to promote the thinning and clearance of mucus (Homayoun Elahi, 2015). The recommended daily dose for an adult is between 600 mg and 2 g.
Re-establishing a balanced gut microbiome.
The gut microbiome is the subject of intense research because of its multiple implications in all aspects of health. A balanced gut microbiome is linked to a healthy immune system (Zheng et al., 2020). Treating ‘leaky gut’ (if suspected) is a starting point of a naturopathic approach to addressing hay fever. Having a varied diet promotes a diverse microbiome, and should include fermented foods (yogurt, kefir, sauerkraut, kimchi, pickles) as well as prebiotic foods (onions, garlic, leeks, asparagus, chicory root, oatmeal, bananas, apples, artichokes, dandelion greens, flaxseed, seaweed, cacao nibs) unless advised against by a professional (FODMAP diet for example). A few studies have looked at the effects of specific probiotics strains on allergic rhinitis symptoms. Supplementing with a combination of 1.25 billions CFU (colony-forming units) of Lactobacillus acidophilus (L. acidophilus) NCFM and 3.75 billions CFU of Bifidobacterium lactis (B. lactis) B1-04 helps in reducing nasal symptoms of birch pollen allergy (Ouwehand et al., 2009). Supplementing with Lactobacillus paracasei (L. paracasei) ST11 helps reduce nasal symptoms of grass pollen allergy (Wassenberg et al., 2011).
Herbs to help relieve symptoms of hay fever
When using a herbal approach to relieve symptoms of hay fever, it is crucial to address the underlying hypersensitivity and hyperreactivity as well as the inflammation while addressing the symptoms (stuffy nose, tearing eyes, headaches, etc.)
Herbs that reduce hyper-sensitivity and hyper-reactivity of the mucosal membranes and airways:
Stinging nettles (Urtica dioica): stinging nettles leaves contain histamine (that cause the itching/burning reaction when touching them), which paradoxically help relieving hay fever symptoms by blocking histamine receptors and inhibiting mast cells degranulation (Roschek et al., 2009).
Stinging nettles can reduce histamine levels and alleviate symptoms of hay fever
Ginkgo (Ginkgo biloba): ginkgo leaves contain compounds that have an anti platelet-activating factor (PAF) activity, which is thought to be useful to reduce respiratory symptoms of allergies (Kurihara et al., 1989; Muñoz-Cano et al., 2019).
Ginkgo can help relieving some of the respiratory symptoms associated with allergic rhinitis
Eyebright (Euphrasia officinalis): eyebright is an undisputed traditional remedy for symptoms of hay fever such as post-nasal drip, nasal congestion. The tea can also be used to make eye compresses to relieve itchy eyes.
Eyebright can help reduce nasal congestion and sore eyes
Feverfew (Tanacetum parthenium): feverfew has the ability to inhibit the release of histamine and prostaglandins and therefore reduce symptoms of allergic rhinitis (Pareek et al., 2011).
Feverfew has been used for centuries to relieve symptoms of hay fever
Peppermint (Mentha piperita): peppermint is a useful addition to any treatment targeting symptoms of allergic rhinitis, it has decongestant effects, calms bronchospasms, and inhibits histamine release (Inoue et al., 2002).
Peppermint is very useful in reducing bronchospasms and the feeling of tightening in the airways
Herbs that help reduce mucus secretions:
Ribwort plantain (Plantago lanceolata): plantain leaves help reduce mucus secretions and congestion associated with allergic rhinitis (Shen et al., 2016). Compounds found in plantain leaves are also anti-inflammatory and anti-oxidant and reduce the production of histamine.
Plantain helps thinning mucus and reduce sensation of stuffiness in the sinuses
Horseradish (Armoracia rusticana): horseradish helps thinning mucus secretions and decongesting the sinuses (Ciuman, 2012).
Goldenrod (Solidago virgaurea): goldenrod has been used for centuries for catarrhal and sinus conditions, it is a decongestant and is effective in alleviating symptoms of hay fever and asthma (McIntyre, 2019).
Goldenrod can help reducing the severity of symptoms of hay fever and asthma
Other natural substances that can provide relief from hay fever
Propolis: propolis is a substance produced by bees that helps make the walls of the beehive more solid and less vulnerable to infectious agents. In humans, propolis has been found to be antiseptic, anti-inflammatory, antioxidant, antibacterial, antifungal, and have immunomodulatory properties (Pasupuleti et al., 2017). Taking propolis for a few weeks before the hay fever season might help reducing symptoms (Shinmei et al., 2009).
Organic local honey: honey has multiple proven properties such as antibacterial, antifungal, antiseptic, wound healing (Mandal & Mandal, 2011) and can be used to alleviate symptoms of allergic rhinitis (Asha’ari et al., 2013).
Honey and propolis can be used to reduce the severity of allergic rhinitis symptoms if taken for a few weeks before the start of hay fever season
In conclusion, natural remedies have been shown to provide substantial relief from symptoms of hay fever, including sneezing, itchy eyes, stuffy nose, shortness of breath. They are safe to be used in conjunction with conventional medicines (prescription or over the counter drugs) or to be used for a few weeks prior to the start of the hay fever season to reduce the severity of allergic symptoms. A balanced diet and targeted supplements can also be of great help for sufferers.
Authored by: Marie-Caroline Cotel for City Alternative Therapies ©
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