The UK is not a good yardstick to judge healthy weight by. High levels of overweight here among all races (also, a lot of UK TV drama portrays the UK as a lot whiter than it actually is - our major cities & more modern towns are as ethnically diverse as the US equivalent). However, there's less extreme obesity here - likely as portion sizes tend to be smaller (soda cups larger than 20oz are a rarity, for example).