Income raises human well-being indefinitely, but age consistently slashes it

Abstract

The relationships among human well-being, income, and age have long been debated. The association between human well-being and income is believed to be U-shaped, although the reasons remain elusive. A recent study shows a turning point in the link between human well-being and income; that is, increased income does not always improve well-being. However, the mechanisms of the effects of income and age on human well-being are unknown. Here, we illustrate the total cumulative effects of income and age on evaluated well-being through all observed causal pathways based on a 1.6-million-observation global dataset and the structural causal model. This is the first study to investigate those casual relationships globally. We find that an increase in age always reduces evaluated well-being, and the adverse effects are aggravated with age. Furthermore, increased income continuously improves human well-being, but the impacts gradually become marginal with higher income. Our results demonstrate that physical health improvement in older people is the most effective way to intervene against the harmful effects of age on well-being. Moreover, increased income may dramatically enhance the well-being of people living close to the poverty line.

Figure 1

The DAG of the relationships among variables. ($\mathit{UNE}$, $\mathit{TWR}$, $\mathit{LGH}$, $\mathit{ENJ}$, $\mathit{INT}$, $\mathit{WLR}$, $\mathit{STR}$, $\mathit{SDN}$, $\mathit{ANG}$, $\mathit{WRR}$, $\mathit{PHP}$, $\mathit{HPD}$, $\mathit{INC}$, $\mathit{NOF}$, $\mathit{NOH}$, $\mathit{SPT}$, $\mathit{SRH}$, $\mathit{SES}$, $\mathit{SAQ}$, $\mathit{SWQ}$, $\mathit{SHC}$, $\mathit{SAH}$, $\mathit{RTL}$, $\mathit{STC}$, $\mathit{MAC}$, and $\mathit{LE}$ are unemployment, feeling treated with respect, smiling or laughing, enjoyment, feeling something interesting, feeling well-rested, stress, anger, worry, physical pain, disability due to health problem, logarithm of individual income, Insufficient food index, insufficient shelter index, satisfaction with public transportation, roads and highways, educational system, quality of air, quality of water, quality of healthcare, and availability of housing, satisfaction with the city, recommending the city to their friends, moving away from the city and life evaluation).

Figure 2

The distribution between the total cumulative effects of age on SWB and age.

Figure 3

The distribution between the total cumulative effects of income on SWB.

Figure 4

The distribution between the total cumulative effects of age on income.

Figure 5

The summary of total cumulative effects of age on life evaluation by country.

Figure 6

Distribution between the total cumulative effects of age on SWB and age by continent.

Figure 7

Map of the country-level average total cumulative effects of age on SWB.

Figure 8

The summary of total cumulative effects of income on life evaluation by country.

Figure 9

Distribution between the total cumulative effects of income on SWB and income by continent.

Figure 10

Map of country-level average total cumulative effects of income on SWB.

Figure 11

The summary of total cumulative effects of age on income by country.

Figure 12

Distribution between the total cumulative effects of age on income and age by continent.