In The Spirit Level, Richard Wilkinson and Kate Pickett claim that “unequal societies are almost always unhealthy societies.” Some new research provides laboratory evidence for this.
Armin Falk and colleagues conducted a simple experiment. They split people into pairs. One person had to do a tedious job, of counting the number of zeros on sheets of numbers, with the pair being paid according to the number of correct answers. The other was given the role of boss, who did nothing except decide how to allocate the revenue thus generated between himself and the worker.
They found that “workers” who felt they were unfairly paid had significantly lower heart rate variability than those with less sense of unfairness.
This matters, because it’s thought that low HRV can predict heart failure.
Falk and colleagues corroborate this by showing that survey evidence links perceptions of being unfairly paid with subjective assessments of personal health.
What we have here, then, is clean micro-level evidence for a link between a sense of unfairness and physiological symptoms.
This is significant. Wilkinson and Pickett’s evidence - which is based mainly upon cross-country correlations between inequality and life expectancy - has been strongly criticized for relying upon a selective sample of data. This evidence, though, seems more robust - it's less vulnerable to the omitted variables bias if nothing else; it‘s reasonable to suppose that if something as trivial as a lab experiment can provoke changes in HRV, then the real world of longer-lasting senses of grievance might also do so, and probably to a greater extent.
There is, though, a slight caveat here. Falk and colleagues are measuring subjective senses of fairness. This means that a man who gets a £1m bonus but who thinks he deserves a £2m one will - ceteris paribus - have lower HRV than a minimum wage worker who feels fairly treated. I‘m not sure, though, that this undermines the basic point, which is that inequality really is bad for health.