Belgians who work full time have bodies that suggest they are a full six years older than they really are. That is the attention-grabbing conclusion of a study carried out for NN insurers (previously Delta Lloyd).

The study is based on a number of questions posed by data consultants 365Analytics regarding lifestyle and stress. The 1,900 respondents were all between the ages of 20 and 65.

The questions involved eating and exercise habits, as well as number of hours of sleep a night and general feelings of well-being. Analysis of their answers to an online questionnaire shows that the average Belgian is biologically six years older than they really are.

The results are largely due to a lack of exercise, according to NN. Nearly half of the respondents are considered overweight by medical standards. And 60% do not get enough sleep during the week.

One notable finding is that those at higher incomes levels, such as CEOs and managers, as well as the self-employed, score much better. Although these business leaders seem to appreciate the benefits of a healthy lifestyle, that doesn’t translate to efforts made for their workers: 57% of workers said that their employers made little to no effort to encourage healthy lifestyles at work.

If you want to know your biological age, take the test (in French and Dutch).