In some countries there is a rise in number of people who are facing health issues from excessive fast-food consumption. Some people believe that governments should impose a higher tax on fast food. But, in my view this may not work as expected.
People develop unhealthy food habits over the years and raising taxes might not result in people spending less on such foods. People may consider eating at their preferred fast food chain and save money elsewhere. For example, someone fond of deep fried chicken will not change their habit just because the prices went up. It is an essential part of their life and they would try to save money in some other way, such as buying groceries in bulk.
Although, raising taxes of fast food is not futile. It will influence a small section of the society, usually poor people, since they spend majority of their income on food. They are more likely to consume less fast food if the taxes are raised.
However, in order to benefit the whole society, governments can implement other better policies to nudge individuals to adopt a healthy lifestyle. For instance, governments can run awareness campaigns to educate citizens about the harmful effects of eating excessive fast food. They can also make fruits and vegetables more affordable to citizens.
Therefore, in my opinion, imposing higher tax on fast food might not help in reducing the number of people eating fast food. But there are other ways for the government to tackle this problem.