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What is cystic fibrosis?

Cystic fibrosis (CF) is a life-limiting inherited condition caused by a faulty gene that controls the movement of salt and water in and out of cells. This causes mucus to gather in the lungs and digestive system and creates a range of challenging symptoms. 

More than 2.5 million people in the UK carry the faulty gene, around one in 25 of us – most without knowing.

There is currently no cure for cystic fibrosis but many treatments are available to manage it, including physiotherapy, exercise, medication and nutrition.

Each week five babies are born with cystic fibrosis, and two people die.

More than half of the cystic fibrosis population in the UK will live past 41, and improved care and treatments mean that a baby born today is expected to live even longer.

We believe that the day when people with CF can live a life unlimited by their condition is within our reach.


The mucus in the lungs of people with cystic fibrosis contributes to a range of issues, making it hard to breath and increasing the risk of infection.

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Digestive system

People with cystic fibrosis struggle to digest food properly, often requiring enzymes at mealtimes to help them.

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How is it diagnosed?

Find out all about diagnosis (newborn or later in life) and what support and resources are available to help you make sense of it all.

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Heel prick test on baby

Are you a carrier?

Read about tests to see if you're one of the 1 in 25 people in the UK who carry a cystic fibrosis gene, and what it could mean for you.

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What causes CF?

Mutations, alleles and DNA - talking about genetics can be confusing! Discover more about the cause of cystic fibrosis and what it all means.

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Scientist cutting DNA model

Find out more about cystic fibrosis, including stories from inspiring individuals living with the condition in our 'is' magazine and helpful factsheets on a wide range of associated medical and social issues.

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Check out the most commonly asked questions about cystic fibrosis.

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Find out more about the treatments and medications to help manage the symptoms of cystic fibrosis.

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Related conditions

Cystic fibrosis can cause related conditions such as CF-related diabetes or osteoporosis. Find out more about what to look out for and the treatments available to manage these conditions. 

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