What is cystic fibrosis?
Cystic fibrosis (CF) is an inherited condition, meaning people with the condition are born with it. It affects the balance of salt and water in some parts of the body. This causes sticky mucus to build up in the lungs, gut and some other parts of the digestive system. It is a life-long condition.
What causes cystic fibrosis?
Cystic fibrosis is an inherited condition. This means it’s caused by genes.
Genes are instructions that tell the body how to grow and function. Every cell in our bodies contains thousands of genes. People with CF have a fault in a gene called CFTR. This gene helps to control the movement of salt and water in and out of the cells.
Everyone has two CFTR genes, one from each parent. 1 in 25 of us carries a faulty CFTR gene. Having one copy of the faulty gene does not affect your health. However, babies who have inherited two faulty CFTR genes from their birth parents are born with CF.
Learn more about how the CFTR gene is inherited.
How does cystic fibrosis affect the body?
People with CF often have sticky mucus in their lungs. Germs can grow in the mucus, causing lung infections.
Mucus can also block parts of the digestive system. This can affect how food travels through the gut and how it’s digested. This means people with CF are less able to get nutrients from food. So, they may need to eat more to stay a healthy weight.
CF can sometimes affect reproductive health and male fertility.
Find out more
How is cystic fibrosis diagnosed?
How is cystic fibrosis treated?
Ways to manage cystic fibrosis