What Is An Asthma Diet?

A balanced diet helps maintain overall physical and mental health. Certain foods and nutrients may specifically help symptoms of asthma. Other foods may be helpful to avoid because they trigger symptoms.

Helpful and harmful foods vary for every person. No single food or vitamin will improve symptoms for everyone. There is not much conclusive research on which nutrients help symptoms. But a diet with a variety of vitamins and nutrients can help you stay healthy. It is important to talk to your doctor before making any changes to your diet.

How does diet affect asthma symptoms?

A well-balanced diet helps keep us healthy and strong. It gives us energy and supports our immune system. A healthy body weight also helps our immune system and lung function. Losing even a little weight can improve asthma symptoms.^1,2

Our diet directly impacts inflammation in the airways, which is a central cause of asthma. In the United States, our diet tends to be higher in processed foods and meats, and lower in fruits and vegetables. This diet promotes inflammation because it has fewer antioxidants and more unhealthy fats. A diet with more fruits, vegetables, and healthy fats seems to reduce inflammation.^3,4

What foods can help my asthma symptoms?

Vitamin D

Vitamin D helps the immune system and reduces airway inflammation. Low vitamin D levels are linked to a higher risk of asthma attacks. Adults with asthma may benefit from vitamin D supplements. However, we do not yet have conclusive evidence that vitamin D supplements improve asthma symptoms.^4-6

Some foods with vitamin D include:⁷

• Fortified milk
• Salmon
• Orange juice
• Eggs

Most of our vitamin D comes from exposure to the sun. Spending a few minutes outdoors in the sun can increase your levels of vitamin D.

Antioxidants

Antioxidants may help reduce airway inflammation by reducing toxic chemicals called free radicals. However, we do not yet have conclusive evidence that antioxidants improve asthma symptoms. The main dietary antioxidants are vitamins A, C, and E. Some foods with these antioxidants include:^4,8

• Vitamin A – Fruits and vegetables, whole milk, liver, eggs
• Vitamin C – Fruits and vegetables
• Vitamin E – Nuts, seeds, green vegetables, vegetable oils

Omega-3 fatty acids

Omega-3 fatty acids may reduce airway inflammation. Some studies have shown the benefits of omega-3 fatty acids, especially in exercise-induced asthma. Some foods with omega-3 fatty acids include:^1,3

• Certain fish, including tuna, trout, and salmon
• Canola and soybean oil
• Walnuts
• Flaxseed

What foods should I avoid in my diet?

If you are allergic to any foods, avoid those foods. Some foods worsen asthma symptoms for some people but not others. If you want to try changing your diet, talk to your doctor. They can suggest ways to avoid certain foods while maintaining a healthy diet. There are some foods and nutrients that commonly cause problems for people with asthma:⁷

Sulfites

Sulfites are used as a preservative in wine and some foods. Sulfites are a common allergen for people with asthma and other atopic conditions. They may cause allergic reactions and worsen asthma symptoms within minutes. Some foods that may have sulfites include:^1,7

• Dried fruits
• Pickled foods
• Shrimp
• Maraschino cherries
• Bottled lemon or lime juices
• Alcohol, especially red wine

Foods that cause gas

Gas and bloating may make breathing harder. This can cause asthma episodes and chest tightness. Some foods that often cause gas include:⁷

• Beans
• Carbonated drinks
• Onions
• Garlic
• Fried foods

Salicylates

Salicylates are naturally occurring chemical compounds found in many plants. Some people with asthma may be sensitive to salicylates. Some foods and drinks that have salicylates include:⁷

• Coffee and tea
• Beer
• Fruits and vegetables
• Sweet potatoes
• Nuts
• Olive oil
• Aspirin