In the teenage years, it remains important to follow your low protein diet to control your blood phe levels. You may have started to take more control of your own diet which you will need to embrace alongside other changes in your life such as starting school or new hobbies. Becoming a teenager brings about many changes to your body and mind, growth spurts, increased physical activity and changes to hormones. This can all have an effect on your blood phe and it may be necessary for more blood spot monitoring during this time. Despite these challenges, it is essential that you consume a healthy balanced PKU diet, which includes enough energy and nutrients to grow, be active and generally be the best version of you! There are lots of benefits for you in following the diet, one of which is keeping your blood phe levels in the correct range. In this section, the potential impact of high phe levels – both short- and long-term shall be looked at.