Susan Keogh meets Mark and Peter Lavery who suffer with a condition called Phenylketonuria– better known as PKU.

They lack the enzyme that breaks down the amino acid Phenylalanine which is found in proteins – this means they cannot eat foods such as milk, eggs, regular bread, fish, cheese, milk chocolate, nuts & tofu.

PKU Association (PKU.ie) & their Facebook group are available online for people who are looking for information, advice and support from others who have been affected by the disease.