Although there are no specific dietary recommendations for people with asthma, research has shown that several foods support lung function, improve the body’s immune system, and reduce asthma symptoms. However, certain foods may worsen asthma symptoms or increase the likelihood of it developing.
Asthma is a common chronic condition. According to the Centers for Disease Control and Prevention (CDC), just under 25 million people in the United States have asthma, with children making up around a fifth of this number.
An article in Nutrition Reviews states that asthma is more common in African Americans and people of lower socioeconomic status.
This article looks at what foods people with asthma may wish to avoid, what foods may improve or even prevent asthma symptoms from developing, and lifestyle factors that may help a person manage this chronic condition.
The American Lung Association (ALA) has identified key foods and drinks that people with asthma may wish to avoid because they may worsen asthma symptoms.
Foods that contain sulfites
Sulfites are a type of preservative often found in preserved food and drink, such as alcohol, pickled foods, bottled lemon and lime juice, and dried fruits.
People with asthma who have high levels of sulfites in their diet may find their asthma symptoms worsen. The ALA warn that foods containing sulfites, particularly wine, may even trigger an asthma attack. A 2018 study confirms that white wine can lead to intolerance reactions in people with asthma.
Salicylates are compounds found in teas, coffees, spicy food, or foods flavored with herbs. Although rare, people with asthma are sometimes sensitive to these compounds and might be more likely to experience a flare-up of symptoms.
A 2013 study looking at the consumption of fast food in children and teenagers found that those who consumed fast food three times a week or more were more likely to develop severe asthma, as well as other health conditions.
The following foods may have some benefits for people with asthma.
Vitamin D foods or supplements
Evidence suggests that low levels of vitamin D have links to an increased risk of asthma attacks in children and adults. It also indicates that taking a vitamin D supplement every day can significantly reduce the risk of hospital admission for a severe asthma attack.
Vitamin D may also support lung function and reduce upper respiratory infections, such as the common cold.
Vitamin D occurs naturally in just a few foods, so most people in the U.S. get their dietary vitamin D from fortified foods, such as breakfast cereals, yogurt, and orange juice.
Good food sources of vitamin D include:
- fatty fish, such as salmon, tuna, and mackerel
- egg yolks
Fresh fruit and vegetables
A healthful, balanced diet rich in fruit and vegetables may reduce the risk of developing asthma.
A 2020 article states that several studies have found that high consumption of fruit and vegetables reduces the risk of adults and children developing asthma.
A 2017 review of over 80 studies found associations between a high intake of fruit and vegetables and reduced asthma symptoms, such as wheezing.
Fresh fruit and vegetables are rich sources of antioxidants, such as vitamin C, vitamin E, and beta carotene, which help the body fight toxins that may damage tissues.
This, in turn, may help to improve lung function and control the symptoms of asthma.
Rich sources of vitamin C include:
- citrus fruits, such as oranges and grapefruit
- kiwi fruit
- red and green peppers
- baked potatoes
Good sources of vitamin E include:
- nuts, such as almonds, peanuts, and hazelnuts
- sunflower seeds
- fortified foods such as breakfast cereal, fruit juice, margarine, and spreads
Orange and red fruit and vegetables contain beta carotene.
- sweet potatoes
- red and yellow peppers
- dark leafy greens, such as kale and spinach
Flavonoids and selenium
A wide variety of fruits contain flavonoids, including:
- black and green teas
Foods that contain selenium include:
- dairy products
Whole grain foods
Whole grain foods may also play a part in reducing the symptoms of asthma.
A 2017 study found that people who enjoyed a healthful diet, including whole-grain food, experienced fewer asthma symptoms and better control of their condition.
Whole grain foods include whole oats, wholewheat pasta, buckwheat, and bulgur wheat.
People with asthma must identify and avoid triggers that may worsen symptoms or bring on another asthma attack. The ALA provide advice and information on common triggers, including:
- over-the-counter (OTC) medicines, such as aspirin or non-steroidal anti-inflammatory drugs
- common food allergies, such as peanuts and shellfish
- smoke, such as cigarette smoke, campfires, or wood-burning fireplaces
- adverse weather, such as stormy, windy, cold, or humid weather
- air pollution, smog, vehicle exhaust fumes, or chemical fumes
- dander and saliva from animals with fur or feathers
- environmental exposure to dust mites, mold, or spores
The ALA recommend managing asthma proactively. Working with a healthcare provider can help people with asthma develop an action plan to avoid triggers and use their prescribed medication effectively and at the right time.
Keeping an eye on symptoms and recording them will help people with asthma identify what steps they can take to avoid foods, activities, or environments that may cause an asthma attack.
Although there is no specific diet to reduce or prevent asthma, there are many foods that can positively or negatively affect asthma symptoms.
A diet rich in fruit and vegetables and low in fast, fatty, or fried foods can help control asthma symptoms.
Keeping track of triggers and symptoms, and working with a healthcare provider, can help people with asthma control their condition more effectively.