In France, obesity rates among both women and men have risen sharply since 1981, with the trend accelerating since the 1990s. This trend affects both young and older people. However, this trend has not affected all social groups equally. Geographical differences have widened between the North and the East, where obesity rates are highest, and the Île-de-France region and the Mediterranean area, where they are lower. Similarly, the gap between socio-professional categories has widened significantly: since 1992, obesity has increased much more rapidly among farmers and manual laborers than among managers and professionals. Unlike women, the poorest men are not the heaviest. (R.A.)