About 25 million Americans have asthma, according to the Centers for Disease Control and Prevention. Inflammation and narrowing in the airways of the lungs is the primary cause of symptoms associated with this disease.
And while there’s no evidence that any one diet will cure asthma, a growing body of research suggests that certain foods can worsen inflammation, and therefore the severity of asthma, according to Meredith C. McCormack, MD, a professor of medicine and the director of the Johns Hopkins Asthma Precision Medicine Center of Excellence in Baltimore.
“The clinical evidence for dietary changes as a primary treatment for asthma is still evolving, but there’s plenty of evidence that suggests a healthy diet is beneficial,” Dr. McCormack says.
Observational studies on diet and asthma have reported “protective” associations with fruits and vegetables and vitamin E, as well as with high fiber intake, and negative effects with processed meats and sugar-sweetened beverages. More research is needed to show how inflammation-promoting foods are directly linked to asthma, but researchers are looking into the ways that oxidative stress and inflammation, as well as imbalances in the gut microbiome, may play a role in asthma.
McCormack says that she works with her asthma patients to develop nutritional plans that alleviate asthma symptoms and support overall health.
Cassidy Gundersen, PhD, a nutritionist and the owner of Spiro Health and Wellness in Utah, says that she’s also worked with a number of people who were able to find long-lasting relief from asthma with dietary changes.
In addition to following a healthy diet, you might want to talk to your doctor about whether avoiding these five types of foods and drinks could help improve your asthma management. Remember, no dietary changes should be used in place of asthma treatment prescribed by your healthcare provider.
When consumed in large amounts, certain food additives can trigger asthma, notes the Cleveland Clinic. And the calorie-free sweetener aspartame, commonly used in diet sodas, is one of many food additives suspected of causing adverse reactions in people with asthma, according to the Asthma and Allergy Foundation of America.
“Food allergy symptoms can mirror — or even worsen — the symptoms of asthma, and vice versa,” says Peg Strub, MD, an allergy specialist in the San Francisco area. It’s best for people with breathing difficulties to avoid chemicals like aspartame that might cause allergic reactions, she says.
“A lot of highly processed foods, such as fast foods, deep-fried foods, packaged foods, and frozen foods, seem to increase asthma symptoms,” McCormack says. She advises her asthma patients to limit these foods and instead focus on in-season whole fruits and vegetables.
The traditional Western diet is high in saturated fat and processed foods. Some research has shown that a Mediterranean diet, which emphasizes fruits and vegetables, whole grains, and lean meats, is associated with reduced wheezing and asthma-related symptoms. Some studies have also found that eating processed meat, in particular, worsens asthma symptoms.Many processed foods contain additives in the form of preservatives and artificial colorings that may worsen lung inflammation. Although the evidence for the effect of specific additives on asthma symptoms is limited, you may want to be wary of the following:
Tartrazine: This is a dye used in sugary drinks, ice cream, and hot dogs.
Nitrates and nitrites: These preservatives are used in processed meats such as hot dogs, bologna, and salami. A study of over 400 Italian children found that exposure to nitrates and acrylamide (a chemical that can form in some foods during high-heat cooking processes) was significantly higher in asthmatic children.
Foods that are high in saturated fat — such as some desserts and baked goods, fatty cuts of red meat, and others — contribute to obesity, which can worsen inflammation and lung function and exacerbate your asthma symptoms, according to research. Maintaining a healthy weight is vital when you have a chronic health condition like asthma, McCormack says. If you’re overweight, your lungs have to work harder, she adds, which can aggravate asthma symptoms.
Not all fats should be limited or avoided, however. McCormack emphasizes that some fats, such as the omega-3 fatty acids found in oily fish, are healthy for people with asthma. “Substituting fish for red meat whenever possible is always a good idea,” McCormack says.
Avocados, walnuts, and seeds are also good sources of omega-3s. One study found that a higher intake of omega-3 fatty acids was associated with better asthma control, lower doses of inhaled corticosteroid medication and lower levels of systemic inflammatory markers, though more research is needed.
Wine contains sulfites, some of which are naturally occurring in the fermentation process and some of which may be added as preservatives. The same goes for beer. Sulfites have been known to worsen asthma in those with moderate to severe symptoms. About 4 to 5 percent of people with asthma have some form of sulfite sensitivity.Additionally, sulfites can be found in dried fruit, shrimp, pickles, and certain condiments. Jennifer Musser, a registered dietitian in Denver who works with adults with inflammation-related chronic conditions (including asthma), says it’s best to avoid them — or at least limit your intake — if you have chronic breathing problems. It’s also a good idea to speak with a doctor for insight into what to avoid and what to do if you have a reaction.
Research has increasingly shown an association between the consumption of sugary beverages and asthma. One study from the United Kingdom that included 210,339 participants found a higher incidence of asthma in people who consumed more than two units a day of sugar-sweetened beverages and artificially sweetened beverages. Of the study participants, 4,645 developed asthma.Another study of 9,938 children found that childhood consumption of sugar-sweetened beverages was associated with increased odds of childhood asthma — and the larger the dose, the greater the risk. Researchers noted, however, that controlled trials are needed to confirm a causal relationship.And an analysis of 11 studies including more than 164,000 children and teens found a significant positive association between the consumption of sugar-sweetened beverages and the odds of asthma. The review authors noted that unabsorbed excess-free-fructose triggers inflammation in the respiratory system and that total excess free fructose intake increases children’s asthma odds by 2.7 times. Excess-free-fructose occurs when the fructose-to-glucose ratio exceeds 1:1, as it does with high fructose corn syrup and apple juice (though most natural foods have a 1:1 fructose to glucose ratio).While some studies have found an association between fruit juice — which is naturally high in sugars — and asthma, others haven’t demonstrated a significant connection. This could have to do with the beneficial nutrients and vitamins in fruit juice, which may offer a protective effect.
While there is no special diet that can reverse asthma, reducing your consumption of certain foods like processed meats, artificial sweeteners, sugary beverages, and fried, fatty foods may help lessen inflammation and alleviate symptoms.
Incorporating more fruits, vegetables, and foods rich in omega-3 fatty acids into your diet might provide some protection against asthma, due to their anti-inflammatory properties, although more research is needed to establish direct effects.
Exercise caution when consuming alcoholic beverages like wine and beer, as the sulfites in these beverages can trigger asthma attacks in susceptible individuals.
Always talk to your healthcare provider before making significant dietary changes or if you experience worsening asthma symptoms, to ensure that you’re maintaining an effective management strategy. As with anything, moderation is critical.
Additional reporting by Moira Lawler.
