DS (6) weighs 25kg and is in the 85th percentile of BMI for his height.
At 25.7kg he tips into the overweight.
Should I change his diet?
He eats a lot (not snacks, just big meals) but is incredibly active. He is also almost pure muscle and very very strong. He can run faster than me. He does judo once a week and swimming twice a week. He runs in the park every day.
After lunch and dinner he has a big tummy but when he gets up in the morning he is slim.
His dad has a fast metablolism and is slim. I was slim until having DS1 but still have a healthy BMI.
He is always asking for more food after his meals but we do say no.
Atlantic, food volume as well as content is a major issue as people get older. Without seeing the exact amount and what exactly he's eating I just couldn't judge. I think you are probably the only one who can. Having said that, parents are often quite delusional about what their kids are actually eating so I don't know if that's the case here either. If you are confident he's not eating two flavoured yogurts, a bag of crisps, a load of raisins, nuggets and chips etc every day (notes all those are fine as a treat but not daily) then portion control is for you to judge. How you cut portions for a hungry 6 yr old I've no idea!
Sounds great OP. I'd just keep an eye on his weight over the next few years. Everyone is different body and metabolism wise so it's important to teach him how to eat for his own body but at 6 and with such a good diet and exercise, I'd be watching carefully for now.
My DS is 12 and has always been right at the top end of the healthy weight scale, ever since he was a baby. Literally a couple of extra pounds would push him over into the overweight category. He is also quite tall for his age. Like your DS, mine very rarely eats 'junk' food and always has healthy homemade meals at home. He walks to and from school, plays football and cricket and is generally quite active. I've stopped worrying now as I think this is just the way he is. He is 'solid' if you know what I mean. Heavily set, big bones (would make a good rugby player except he doesn't like rugby!) I think as long as he keeps eating healthily and getting plenty of exercise then you're doing a great job.
Also, meant to say, my DSS is 14 and is as skinny as a rake. He eats loads of junk food, chips, takeaways, fried foods, crisps, chocolate etc (his mum isn't bothered) yet he is stick thin. It doesn't make sense! He eats healthily when he is with us yet still constantly asks for sweets etc. Maybe it's just they have different metabolisms. I would rather DS be bigger and eat healthily than thin but living on crap, iyswim.
BMI is not a be-all-and-end-all measure. Most professional athletes will likely be classed as overweight or even obese in the case of some rugby players. That does not mean that they are unhealthy or fat. Like someone else said, muscle weighs more than fat. Body composition is just as important as overall weight.
If he has very little fat, a lot of lean muscle,and is as active as you say, I can't see a problem. He sounds really healthy and a sensible eater.
He may be hungry all the time because he is so active on top of being at an age when his body is growing quite fast. Try to give him more lean protein throughout the day, such as eggs for breakfast. Protein takes longer to metabolise and keeps you feeling satiated for longer.