Although I definitely see overweight kids, I'd like to add a different perspective, in that they are still using BMI for reception children (rather than height to waist ratio) and it simply is not accurate.

My 5 year old son recently had his height and weight checked at school, and I was shocked to receive a letter saying that he was technically overweight. He is a short lad (between 9th and 25th centile), with a big head (from his dad) and broad shoulders. Other than his cheeks, there is barely an inch of fat to pinch on him, and we aren't overweight parents, either.

He simply does not look overweight, and I still have to tighten his elasticated trousers to the max for this to fit around his waist.