Asthma alert: can healthful eating lead to better breathing?
Asthma has skyrocketed in the U.S.; the prevalence of asthma doubled between 1986 and 2005, and it is now estimated that 9.5 percent of children and 7.7 percent of adults have asthma. Obesity is known to compromise proper function of the lungs and airways and is associated with asthma-related inflammation. Increased prevalence of asthma among obese individuals has been demonstrated in children and adults. As body mass index (BMI) increases, asthma risk increases. It is now thought that the rise inchildhood obesity is another causative factor for the recent rise in asthma.1-3,4
In addition to obesity, metabolic abnormalities in children and teens, such as high cholesterol, high triglycerides, and hyperinsulinemia, regardless of body weight, have now been associated with asthma. Also, regardless of their weight, children who drink more sugar-sweetened beverages are more likely to be diagnosed with asthma.5 This means that even if a child is of normal BMI, the standard American diet is likely taking its toll on lung function, producing early metabolic abnormalities that may set the stage for asthma, obesity, diabetes, and other chronic diseases.6 On the other hand, there is evidence that vegetable and fruit consumption and adequate antioxidant vitamin intake help to protect children against asthma.7 Of course, these same dietary factors also promote a healthy weight and protect against chronic diseases in later life.
Weight loss has been shown to improve asthma symptoms in obese children.8 In adults who have asthma, there is evidence that a single high-calorie, low-nutrient meal can spark airway inflammation, which can exacerbate asthma symptoms. Asthmatic adults consuming a single high-calorie, low nutrient meal, high in animal protein and added fat (1,000 calories worth of fast food hamburgers and hash browns) experienced increased airway inflammation four hours later. Researchers compared this to a 200 calorie meal, which did not increase inflammation.9
Obesity, resulting from the cumulative effects of years of overeating low-nutrient, high-calorie food is a risk factor for asthma. However, deleterious effects of a low-nutrient diet on lung function occur even in the short term, and can begin early in life. Children at normal BMI with poor diets or metabolic abnormalities are at risk, and the body reacts with increased airway inflammation even from a single, low nutrient meal. Collectively, these studies tell us that asthma is another disease whose major causes include poor nutrition and a sedentary lifestyle.
Since asthma is both a lifestyle and inflammation-related disease, dietary changes and weight loss are extremely effective at improving asthma symptoms. A high-nutrient diet floods the body with protective micronutrients, reduces inflammation, and promotes weight loss—allowing the body to resolve the risk factors for asthma mentioned above (obesity, high cholesterol, etc.). With a good diet, many patients with asthma recover completely and no longer need asthma medication.
Reducing or eliminating asthma medications is a worthwhile goal, since long-acting beta-agonists have been linked to serious adverse events, and inhaled corticosteroids at high doses are associated with adrenal suppression, reduced bone density, and other issues.10-12,13 Long-acting beta agonists (which are often used in combination inhalers with steroids) may worsen asthma control with time.14Short acting beta-agonists relieve immediate symptoms, but may also exacerbate the condition over time, as more frequent use is associated with an increased number of asthma events in the future.15So as you take more drugs, you create a vicious cycle of needing more drugs.
In addition, the overuse and misuse of antibiotics also can make children more prone to asthma.16-18 Nutritional diets reduces chronic mucous, inflammation and incidence of recurrent infections. Most of these antibiotics are given to infants and toddlers with viral infections and viral otitis (ear infection), which combined with poor nutrition puts them on the road to asthma.
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