We often focus on calories, protein, pancreatic enzymes, salt, and fat-soluble vitamins when talking about nutrition and CF. But antioxidants are important too.

Antioxidants are nutrients and compounds that help protect the body from oxidative stress. Oxidative stress happens when there is an imbalance between free radicals, which can damage cells, and the body’s ability to neutralize them. Free radicals are unstable molecules that are formed naturally during normal body processes, including breathing, metabolism, and the immune response. They can also increase during illness, infection, inflammation, exposure to pollution, cigarette smoke, or other environmental stressors. In CF, the lungs and digestive system often deal with chronic inflammation and infection, which can increase the production of free radicals. When the body produces more free radicals than it can neutralize, oxidative stress can occur. In cystic fibrosis, chronic inflammation, infection, and increased demands on the body can contribute to higher levels of oxidative stress.

So where do antioxidants come from? Many are found in everyday foods, especially colorful fruits and vegetables. Berries, oranges, leafy greens, tomatoes, peppers, carrots, sweet potatoes, beans, nuts, seeds, and whole grains all contain antioxidant-rich nutrients and plant compounds. Vitamins A, C, and E are also considered antioxidants, and vitamins A and E are especially important in CF because they are fat-soluble vitamins.

For many people with CF, absorbing fat-soluble vitamins can be challenging, especially when pancreatic insufficiency is present. That is why CF-specific vitamins are often prescribed and monitored through routine lab work. These vitamins are part of maintaining a normal nutritional status.

That said, more is not always better. High-dose antioxidant supplements should not be started without guidance from a CF care team. Some vitamins, especially fat-soluble vitamins like A and E, can build up in the body if taken in excessive amounts. The best approach is usually a combination of food-first nutrition, prescribed CF vitamins, pancreatic enzymes when needed, and regular monitoring of vitamin levels.

A simple way to increase antioxidant intake is to “eat the rainbow”. Add fruit to breakfast, include a vegetable with lunch or dinner, choose colorful sides, and try snacks like trail mix, yogurt with berries, hummus with vegetables, or peanut butter with apple slices. For people who need extra calories, antioxidant-rich foods can still fit into higher-calorie meals and snacks when paired with healthy fats, protein, and energy-dense foods.

In the era of highly effective CFTR modulators, nutrition needs are becoming more individualized. Some people with CF still need a high-calorie, high-fat diet, while others may need a more balanced approach focused on heart health, gut health, blood sugar, body composition, and long-term wellness. Antioxidants fit beautifully into that bigger picture.

Antioxidants will not replace CF medications, enzymes, airway clearance, or vitamins, but they can support overall health as part of a well-rounded CF nutrition plan. The goal is not perfection; it is adding more nourishing, colorful foods in ways that are realistic, enjoyable, and tailored to each person’s needs.