The objective of this article is to analyze and identify if there is enough evidence to assume that obesity, smoking and alcoholism, as well as health spending are variables that determine the behavior of life expectancy at birth. It is a quantitative study based on documentary information obtained from the OECD, with a correlational scope and a non-experimental approach. The results show enough evidence to infer that life expectancy for countriesthat belong to the OECD is being explained more significantly by obesity, alcoholism, and health spending. It is also demonstrated that the life expectancy of the countries included in the study is 80.7 years. It is concluded that in recent years, life expectancy has generally been increasing in most of the countries. Life expectancy is a topic of significant social interest so its research has identified several factors that impact its level. Due to the growing interest, the countries seek to develop policies and programs that would allow them to continue improving life expectancy. Thus, many countries focus their efforts on diminishing the negative impacts of the main affecting variables.