Health depends on a wide range of factors.

A person is born with a range of genes, and in some people, an unusual genetic pattern can lead to a less-than-optimum level of health.

Environmental factors play a role. Sometimes the environment alone is enough to impact health. Other times, an environmental trigger can cause illness in a person who is genetically susceptible.

Access to healthcare plays a role, but the WHO suggests that the following factors may have a bigger impact on health than this:

• where a person lives
• the state of the surrounding environment
• genetics
• income
• education level
• relationships with friends and family

These can be summarized as:

• The social and economic environment: Including how wealthy a family or community is
• The physical environment: Including parasites that exist in an area, or pollution levels
• The person's characteristics and behaviors: Including the genes that a person is born with and their lifestyle choices

According to the WHO, the higher a person's socioeconomic status (SES), the more likely they are to enjoy good health, a good education, a well-paid job, afford good healthcare when their health is threatened.

People with a lower socioeconomic status are more likely to experience stresses related to daily living, such as financial difficulties, marital disruption, and unemployment, as well as social factors, such as marginalization and discrimination. All these add to the risk of poor health.

A low socio-economic status often means less access to healthcare. People in developed countries with universal healthcare services have longer life expectancies than people in developed countries without universal healthcare.

Cultural issues can affect health. The traditions and customs of a society and a family's response to them can have a good or bad impact on health. For example, around the Mediterranean, people are more likely to consume high levels of fruits, vegetables, and olive, and to eat as a family, compared with cultures with a high consumption of fast food.

How a person manages stress will affect health. People who smoke, drink, or take drugs to forget their problems are likely to have more health problems later than someone who combats stress through a healthful diet and exercise.

Men and women are prone to different health factors. In societies where women earn less than men or are less educated, they may be at greater risk than men for poor health.