What is health psychology?Health psychology is the study of behaviour when it comes to health, illness and healthcare. Health psychology focuses on individual strengths and puts emphasis on prevention and adaption during all phases from health to illness. Questions like How to remain healthy for as long as possible? and How to adapt in the most healthy way? are related to this. Health psychologists work in health care (private practice, medical psychology department in the hospital, rehabilitation centres, medical centres), research, policy (local or federal government, developmental aid organisations) and primary prevention and training centres (Hersenstichting, KWF, Voorlichtingsbureau Voeding). How can we prevent unhealthy behaviour?There are three forms of prevention. Primary prevention is a method to keep people healthy for as long as possible. The target group of this form of prevention is healthy people. Secondary prevention focuses on finding early signs of an illness. This is done by screening and early treatment. The symptoms that may occur are still reversible at this stage. The target group for secondary prevention is (healthy) people with an increased risk of developing a certain condition. Tertiary prevention is based on the prevention of symptoms growing worse and rehabilitation. The people who this type of prevention is aimed at have already developed a certain condition. What is ‘health’?There are different opinions on the exact meaning of health. Some people see health as being not ill, which means showing no symptoms and not having to visit a doctor. Others see health as a reserve/resource (quick recover, strong family), behaviour (looking after yourself), physical fitness and vitality, psychological well-being (being in balance, enjoyment, harmony) or as a function (being able to do what you have to do or what you want to do). According to the WHO, health is a state of complete physical, mental and social well-...