The development of allergies and asthma is a complex interaction of genetic susceptibility and environmental factors, including your diet and nutritional status. The prevalence of allergies and asthma is on the rise in developed countries, particularly in Australia and New Zealand. The exact reason for this increase not entirely clear at this stage, however it may be partly due to our love of highly processed and nutrient poor food choices.
Current research suggests that a Mediterranean-style diet can help to improve symptom management for allergy and asthma sufferers. The mediterranean diet provides an abundance of antioxidants and key nutrients to help reduce inflammation and tame that overzealous immune response.
The Mediterranean Diet
The Mediterranean diet centres around a plant-based, whole food diet with a primary focus on fresh fruit and vegetables, legumes, whole grains, nuts, seeds, olive oil, herbs and spices. Fish and seafood are also consumed on a regular basis, at least twice a week — think small, oily fish like sardines, anchovies and mackerel for all those lovely omega 3 fatty acids. Poultry, eggs and dairy are also eaten frequently, however in smaller portion sizes. Red meat intake is relatively low compared to the typical western diet, and limited to only a few times per month.
The key is to include a wide variety of whole foods in your diet and select seasonal, local and organic produce whenever possible. Fresh, seasonal and local produce, particularly fruits and vegetables, will generally have much higher levels of antioxidants, vitamins and minerals.
Organic and pesticide-free produce
If you have access to pesticide-free or organic produce, then that is fantastic. If you cannot get a hold or organic fruit and vegetables, then you can wash your produce using an unscented detergent such as castille soap or a fruit and vegetable wash. Rinse produce and then soak in a sink of clean, filtered water and vinegar (3 parts water, 1 part vinegar) for 10 minutes to further reduce pesticide residues. Rinse and air dry produce thoroughly and store as appropriate. Dietary exposure to pesticides (dichlorophenols in particular) may potentially affect our microbiome (population of good gut microbes), increasing the risk of allergy and asthma development.
There are several key nutrients, abundant in the mediterranean diet, that have been shown to dampen the allergic response and reduce inflammation. I have also included a list of foods that are rich in these lovely, allergy-fighting nutrients.
Omega 3 fatty acids have a potent anti-inflammatory effect, which can help relieve some of those hay fever, asthma and eczema symptoms. Omega 3 fatty acids are a major component of cell membranes and in combination with Vitamin E, plays a vital role in maintaining the integrity and flexibility of tissue membranes in the respiratory tract, the gastrointestinal tract and the skin. Adequate blood levels of vitamin E is thought to inhibit IgE immune responses (hypersensitivity reactions) to allergens, reducing the frequency and severity of allergic reactions.
Vitamin C is a natural anti-histamine. Histamine is a chemical released from our immune cells, often in response to allergen exposure and contributes to allergy symptoms such as itching, inflammation, swelling, increased mucus production and narrowing of the airways (also known as bronchoconstriction). Vitamin C can help to reduce the allergic response by inhibiting the release of histamine from immune cells and by increasing the breakdown of histamine that is released. Vitamin C also provides antioxidant and anti-inflammatory support and aids in tissue repair.
Bioflavonoids are bioactive compounds found exclusively in plant foods such as fruit, vegetables, herbs, spices, nuts and seeds. Bioflavonoids, in particular quercetin and catechins, have been shown to have powerful anti-inflammatory effects and stabilise those histamine-releasing immune cells.
Dietary fibre is possibly the most important nutrient to help manage your allergy symptoms. Why? Because fibre, specifically soluble fibres known as prebiotics, feed our microbiome (good gut bacteria population) — keeping it healthy, strong and diverse. Although the human digestive tract is not able to breakdown prebiotic fibres, our microbiome can digest them to produce energy for themselves as well as metabolites, that regulate our immune system and keep inflammation in check. These metabolites are the key to minimising the severity of allergenic responses and inflammation.
|Food source of nutrients|
|Omega 3 Fatty Acids||Seafood — Salmon, tuna, trout, herring, mackerel, anchovy, eel, blue mussels, pacific oysters, prawns, scallops.
Vegetarian — Flaxseeds, chia seed, walnuts.
|Vitamin E||Wheatgerm, almonds, walnuts, cashews, sunflower seeds, avocado, brown rice, rice bran oil.|
|Bioflavonoids||Fresh fruits and vegetables, particularly citrus fruits and peels, berries, apricots, tomatoes, capsicum, green tea.|
|Vitamin C||Citrus fruits, strawberries, kiwi fruit, pineapple, tomatoes, capsicum, chillies, fresh herbs, kale, Brussels sprouts, broccoli, spinach.|
|Soluble Fibre/Prebiotics||Vegetables — Jerusalem artichokes, chicory, garlic, onion, leek, shallots, spring onion, asparagus, beetroot, fennel bulb, green peas, snow peas, sweetcorn, savoy cabbage
Legumes — Chickpeas, lentils, red kidney beans, baked beans, soybeans
Fruit Custard apples, nectarines, white peaches, persimmon, tamarillo, watermelon, rambutan, grapefruit, pomegranate. Dried fruit (eg. dates, figs)
Grains and cereals — Barley, rye bread, rye crackers, pasta, gnocchi, couscous, wheat bran, wheat bread, oats
Nuts and seeds — Cashews, pistachio nuts, flaxseeds
Other — Human breast milk
This is not an exhaustive list of beneficial nutrients for allergy sufferers, but the main nutrients with supporting clinical evidence. I also want to stress the importance of taking a dietary approach, rather than the supplement reflex. While it is incredibly tempting to take the easy route and grab yourself a collection of these nutrients in supplement form, Mother Nature is always ten steps ahead. Whole natural foods contain a range of nutrients that usually have a synergistic relationship. Foods that are naturally high in vitamin C such as citrus fruits also contain bioflavonoids. Likewise, most nuts and seeds that provides omega 3 fats, also naturally contain vitamin E and prebiotic fibres. Mother nature provides us with beautiful synergistic nutrients in natural foods, so my advice is to always go with the food-based approach first. Supplement with additional nutrients if you need to and always under the guidance of your healthcare provider, but let me just say this — you cannot out-supplement a Homer Simpson-style diet.
The take home message
As there is a strong genetic link, it is unlikely that we can ever get rid of allergies completely. But, we can do so much through diet alone to better manage allergy symptoms and potentially reduce our reliance on over-the-counter medications. Enjoying a wide variety of colourful, fresh, whole foods is the key. And don’t forget to feed that army of gut microbes — keep these guys happy and well balanced and they will return the favour ten-fold.
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