Fatter people pay the price of being overweight by earning less, a Europe-wide study has found.

For every 10 per cent increase in body mass index (BMI), a man loses 3.27 per cent in earnings, and a woman 1.86 per cent.

The effect is much stronger in the countries of Southern Europe — the Olive Belt — than it is in the “beer belt” of Northern Europe, say the authors, Giorgio Brunello, of the University of Padua, and Béatrice D’Hombres, of the European Commission’s research centre in Ispra, Italy.

One explanation is that fatter people are so common in the beer belt that they are less likely to be discriminated against than are those living in the svelte world of the “olive belt”. But the issue is fraught with difficulties. The most obvious is distinguishing cause from effect: does being overweight reduce earnings, or do lower earnings cause people to be overweight? Poorer people may have an unhealthier diet, or do less exercise, for example.

Writing in Economics and Human Biology, the authors gathered data from the European Statistical Office on more than 40,000 people from nine countries: Greece, Italy, Portugal, Spain, Austria, Belgium, Denmark, Finland and Ireland.

The raw statistics suggest quite a strong link between being overweight and reduced earnings, a 10 per cent increase in BMI being linked to a 3.49 per cent reduction in earnings in women and a 5.29 per cent reduction in men. But when occupations that require physical strength are taken out of the equation the association weakens and the reductions in earnings are roughly halved.

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