Choose an example of a demerit good and and a policy which may be used by the UK Government to help reduce its consumption

A demerit good is a good which is generally both harmful or unhealthy to the consumer - in most instances, they also carry negative externalities, which are costs imposed onto third parties. An example of such a good is fast food, given the well-evidenced health consequences of its regular consumption. The UK Government aims to reduce the consumption of fast food because it can not only cause health problems for individuals themselves, but because it then subsequently passes on these costs externally to other people and the Government itself in the form of greater required expenditure on the NHS. A government policy to help combat its consumption may come in the form of subsidies to help reduce the cost of purchasing healthy foods - such as fresh fruits and vegetables. This would consequently reduce the demand for fast food by cutting the cost of a healthier substitute - both solving the issue and increasing the wellbeing of the populace.