Diet has long informed how society perceives weight and body image

In the last 50 years our diet has been transformed. From boiled beef and carrots to a Big Mac and fries, we have moved from a world of shortages and post-war rationing to one of overabundance.

Pictures of gym classes in the 1950s and 1960s, when Anna Soubry was growing up, show pigeon-chested children with pinched faces and stick thin limbs. The poorer the family, the more stick-like their children – hence her recall of “skinny runts”.

Their counterparts today are made of different stuff: taller, heavier, with developed physiques. And where once malnourishment was the curse of the poor, today it is over-nourishment.

But the association between obesity and poverty is a recent phenomenon. Through most of history, and in many cultures today, weight has been associated with wealth. A man with a belly was one who could afford to eat – and it was likely he ate well.

During the 19th century, height and weight were valued in soldiers and labourers. Military and industrial success depended on strength. Body sizes increased. For a woman, weight was equally important – it determined her fertility. Without a certain amount of adipose tissue, a woman’s monthly ovulatory cycle will cease. If there is not enough food to sustain the present generation there is no point in producing the next.

Evolution has seen to it that the reproductive process shuts down during periods of starvation. Fatness has thus come to be associated with fertility. In Uganda, until the 1960s, the Kabaka (king) gave his many wives an unlimited supply of milk in order to maintain their weight. Their gross obesity was a mark of his importance.

Obesity is still seen as a sign of wealth and health in much of Africa, especially since the HIV-epidemic (also known as Slim Disease) began 30 years ago.

The value placed on being slender in western societies is a recent phenomenon. The wealthy can afford more nutritious food, know how to prepare it, are under greater pressure to be slim and have more opportunities as well as greater expectations of physical fitness.

The poor, however, have to travel further and search harder to find good food. They are less likely to dig up a potato and boil it than take a bag of chips out of the freezer and stick it in the microwave.