The health-wealth gradient is like a ladder, the higher up the more wealth and health.
The relationship between health and income is referred to as a “gradient” to emphasize the gradual relationship between the two; health improves with income throughout the income distribution, and poverty has more than a “threshold” effect on health.
In the NLMS data the proportional relationship between income and mortality is the same at all income levels, which implies that the absolute reduction in mortality for each dollar of income is much larger at the bottom of the income distribution than at the top.
The gradient is often assessed in terms of other variables; mortality declines with wealth, with rank, and with social status. One of the most famous of the current studies links ill health and mortality to occupational grade among Whitehall civil servants (in the United Kingdom); that none of them are poor further illustrates that the gradient is more than an effect of poverty.
Tip! How are income and wealth linked to health and longevity? Visit Urban.org to learn more.