Perhaps the most important benefit of living a healthy lifestyle is that it not only provides the best quality of life but it also helps reduce the likelihood of a person getting ill and of incurring a financial hardship. This is because medical bills are likely to be far lower if the patient has already managed to secure treatment while healthy. The same would also go for prescription drugs: while sick, a person can probably get by with fewer medications than he or she would have had they been healthy.

Illness and health do often co-exist with each other. That is why it is important to maintain a healthy lifestyle. In many countries, even children as young as five have been reported to have diabetes. These diseases are likely to have been caused by lack of exercise and exposure to toxins and contaminants in the environment. Illness and health can also arise from an accumulation of too many diseases (i.e. a single instance of appendicitis for a woman may lead to serious menstrual complications) or from a deficiency of some essential nutrient (for example, iodine).

Many of the social determinants of good health can be improved by adopting a healthy lifestyle. One area where social determinants play a role is education. The ability of people to get and keep a job is highly correlated with their health status. A study carried out in Canada showed that women who completed a post-secondary education had a 50% better chance of staying alive after a first baby (the child being under five years old at the time of the study). Similarly, men were found to live longer if they attended college or university or were employed.

Public health aims to address the gaps that exist between people and the health or wealth that they have access to. The development of a healthy population requires that an effort be made to eliminate the existing social determinants of health and develop new strategies to achieve this. The planning phase of public health seeks to address these gaps and give rise to policies and programmes that will improve the health of the general population. The implementation of strategies to reduce social disparities is known as the implementation phase of health promotion.

The design of a public health program usually involves the following elements: analysis of current trends and practices; assessment of the impact of these trends and practices on the health and well-being of persons; identification of priority areas for change and implementation of plans based on the identified priorities; evaluation of the programmes’ effects on reducing or eliminating the identified threats; and finally, review of the programme’s results to determine whether it is successful in achieving its goals. The design of disease prevention programmes, for example, involves establishing a target population and designing methods of communication regarding the programme to reduce or eliminate the risks posed by the disease. It also involves evaluating the success of the programme in reducing morbidity, mortality and rates of new onset diseases. Analysis of current and past practice on disease prevention and controlling is an important element of the design of a programme for disease prevention.

Public health promotion, meanwhile, aims at the improvement of the quality of life of the general population by addressing conditions that cause poor health and are thus preventable. These include, among others, high blood pressure, diabetes, obesity, smoking, physical inactivity and unhealthy environment. Public health programmes address these problems through interventions that deal with the causes of these problems and the effects these problems have on the individuals living in them. Some examples of interventions addressing physical inactivity are promoting walking or recreational activities and making public places healthy and inviting to physical activity. Other examples of interventions addressing unhealthy environments include creating and promoting spaces for healthy eating and physical activity, creating environments that promote healthy social interaction and physical education, and providing information and support to families towards the goal of physical fitness.