Although asthma is an incurable disease, it is possible to achieve adequate control and treatment in order to improve the quality of life. Following a plant-based diet can help with this goal.
Plant-based nutrition encourages the consumption of foods of plant origin in their most complete, natural, complete, unrefined and minimally processed form (including foods such as whole grains, vegetables, fruit, legumes, seeds, oil fruits and healthy fats), not including animal foods.
Recently, a new and wide-ranging review published in the Nutrition Review at the University of Oxford was able to analyze the associations between asthma and consumption of some foods such as fruits and vegetables, dairy products, eggs and saturated fat, with plant-based nutrition as a tool powerful to prevent and control asthma, while some animal products such as dairy products and other high-fat foods increase the risk and aggravate your symptoms.
According to the Portuguese Society of Pulmonology, asthma is a chronic inflammatory respiratory disease of the bronchi, resulting from their narrowing, causing a sensation of difficulty in breathing and wheezing.
This is a disease that, according to information from the World Health Organization, affects about 235 million people in the world of all ages and genders, and in Portugal it is estimated that it affects more than 600,000 people, from children ( 11% of our children) to adults (5% of adults).
Despite being an incurable disease, it is possible to achieve adequate control and treatment in order to improve the patient’s quality of life. Simultaneously with the traditional pharmacological approach, monitoring nutritional status, physical activity, and food intake is also essential, and the association between food and asthma has been addressed in several studies over the years, showing some promising results with potential clinical impact.
One of the first works that suggested a plant-based diet as a potential treatment option for asthmatic patients dates back to 1985 in Sweden, where its authors tested the effect of changing the dietary pattern for a vegan-type plant-based diet on a set of 35 patients with severe bronchial asthma over 1 year. There was a significant improvement in several clinical variables, including mainly pulmonary function meters, as well as a significant decrease in antibodies associated with the allergic process (such as IgE and ESR), improvement in cholesterol, blood pressure and weight loss. an average of 8 kilos per patient.
Prevent and treat asthma with plant-based foods
The accumulated scientific evidence, including an international study of asthma and allergies in childhood and adolescence, which covered more than one million children, revealed as a protective factor, among the prevalence rates of asthma, allergies and eczema, the ingestion of starchy foods, cereals and naturally rich in antioxidants like fruits and vegetables.
The variation in the consumption of foods rich in antioxidants has also been shown to directly affect the condition of the asthmatic patient, and the omission of foods rich in these components, even for a short period of time (10 days), has led to the worsening of some symptoms of asthma.
On the other hand, the asthmatic patient subject to the reinforced consumption of a diet rich in antioxidants (with 5 servings of vegetables and 2 servings of fruits) instead of a diet low in antioxidants (2 or less servings of vegetables and 1 serving of fruit), had its rate of asthmatic exacerbation halved.
Within these antioxidants from the diet we can include nutrients such as vitamin E and C, carotenoids, flavonoids and selenium, positively associated with lung function in patients with and without asthma. Similarly, increased intake of dietary magnesium sources and a low-salt diet are associated with a positive effect on asthma with improved lung function in patients with exercise-induced asthma.
Vegetable-based diets, as they emphasize the consumption of foods such as fruits, vegetables and whole grains, are also rich in fiber, which has been positively associated with improvements in lung function.
In asthmatic patients, systemic inflammation is associated with worse clinical outcomes, however, plant-based diets potentiate anti-inflammatory markers and reduce pro-inflammatory molecules, where nutrients such as unsaturated fatty acids (especially present in foods such as olive oil, seeds and flaxseed oil, avocado, olives, walnuts and chia seeds) and antioxidants obtained from foods of plant origin have revealed their anti-inflammatory potential and as attenuating conditions triggered by the systemic inflammatory response.
Foods to Avoid in Asthma Control and Treatment
The results of a pilot study that looked at the effect in children with asthma of excluding milk, milk products and eggs for 8 weeks, showed an improvement of an average of 20% in their peak expiratory flow, but they have not been significantly changed in controls, thus lacking this potential connection between dairy products and clinical symptoms from large-scale and longer-term studies.
The mechanisms by which dairy products influence the development or course of asthma are not yet clear, and may include a positive association between the consumption of milk proteins or fats and their derivatives and the pro-inflammatory interleukin 17F, which in turn plays a role mediating role in the development of asthma.
A diet rich in saturated fats, sodium and low in fiber and carbohydrates is related to bronchial reactivity in asthmatic patients, while a plant-based diet is associated with lower rates.
However, until now, the direct scientific evidence that evaluates the prevention and control of asthma through food, namely plant-based, still lacks intervention studies in order to confirm and substantiate these associations.
Nutritionist Holmes Place Coimbra
Lindahl.Olov.M.D., Lindwall.Lars.PhD., Spångberg,Alf., Stenram.Ake.M.D., Ockerman.Per,.Arne.M.D.(1985). Vegan regimen with reduced medication in the treatment of bronchial asthma. Journal of Asthma, 22(1) 45-55, Linkoping S-581 85, Linkoping, Sweden. DOI: 10.3109/02770908509079883
Alwarith.Jihad.,Kahleova.Hana.,Crosby.Lee.,Brooks.Alexa.,Brandon.Lizoralia.,Levin.Susan.M.,Barnard.Neal.D.(2020). The role of nutrition in asthma prevention and treatment.Nutrition Reviews, vol.78, Issue 11, November 2020, 928-938, Oxford Academic. doi.org/10.1093/nutrit/nuaa005
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