Water Scarcity and Life Expectancy at Birth: A Worldwide Analysis

The Water Poverty Index (WPI) is an interdisciplinary measure that links household welfare with water availability and indicates how water scarcity impacts human populations. Water availability and income per capita may play determinant roles in worldwide life expectancy variations.

In this paper we investigate whether the influence of water as a population health determinant is equal around the world. We also include the influence of income per capita on life expectancy as a proxy variable for quality of life and wealth.

We utilized data on the five main components of the WPI (Resources, Access, Capacity, Use, and Environment) for 128 countries plus their corresponding life expectancy and per capita GDP published by the World Bank. A regression model was used to measure the relative influence of each variable on life expectancy at birth.

The grouped analysis shows that these six variables explained 76% of the life expectancy at birth variation. Analysis of variance demonstrated that our model, considered as a whole, is statistically significant. However, taken individually, only two variables were significant predictors, "access" and "capacity". The variable "GDP", included in the "capacity" dimension, was redundant. After segmentation into major continental areas, the model maintains its explanatory power for Asia, Europe, and North and Central America.

In conclusion, water is not considered a determinant of life expectancy at birth for the Middle East and North Africa, South America and Sub-Saharan Africa. Furthermore, limitation in water resources has no significant impact on life expectancy.