Nothing new here if I am anything to go by. I never understand the way people willingly retire, even making the choice themselves. A report by the IEA in London reached these conclusions:

In the past 50 years, labour market participation among older people has declined significantly though the trend has been reversed in
recent years. In the EU, about 70 per cent of people aged between 60 and 64 are inactive….

Whilst people have been retiring earlier on average, they have also been living longer. A 61-year-old man in 1960 had the same probability of dying within a year as a 70-year-old man in 2005.
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Healthy life expectancy at age 65 has also increased in the UK, although at a somewhat slower pace than regular life expectancy. This would suggest that people have the capability to work longer, though perhaps not to increase their working life on a one-for-one basis as life expectancy increases. Life expectancy at age 65 increased by 4.2 years for men between 1981 and 2006. During the same period, healthy life expectancy at age 65 increased by 2.9 years for men.
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Increases in the number of healthy years of life that we can enjoy is the case: people were working longer half a century ago.

If rising pension ages and labour force participation at older ages caused greater ill health then it would be a matter for concern. Most research on the relationship between health and working in old age has produced ambiguous results. Research in this area is difficult because just as the fact that retirement can influence health, health can influence retirement decisions.

To date, research has not generally examined the relationship between the number of years spent in retirement and health. This issue is important. It is possible that health will initially improve when somebody retires and then, after a while, start to deteriorate due to reduced physical activity and social interaction.
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New research presented in this paper indicates that being retired decreases physical, mental and self-assessed health. The adverse effects increase as the number of years spent in retirement increases.
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The results vary somewhat depending on the model and research strategy employed. By way of example, the following results were obtained:

– Retirement increases the probability of suffering from clinical depression by about 40 per cent
– Retirement increases the probability of having at least one diagnosed physical condition by about 60 per cent
– Retirement increases the probability of taking a drug for such a condition by about 60 per cent.

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Higher state pension ages are not only possible (given longer life expectancy) and desirable (given the fiscal cost of state pensions) but later retirement should, in fact, lead to better average health in retirement. As such the government should remove impediments to later retirement that are to be found in state pension systems.

[Via The American Interest who for reasons of their own seem cynical about the motives for producing the report and therefore somewhat sceptical about the results.]