(Further to my post on exercise and my questioning on how much effect it had on a child’s weight gain).
Whilst exercise undoubtedly has some effect on a child’s weight; in my opinion - and picked up by others - the main cause of childhood obesity is sugar. (Refined carbohydrates are equally important I acknowledge but I’ll leave them out of the equation for the sake of argument on this occasion).
From all the research on diet I have undertaken over the last 18 months the single most egregious culprit that is wrecking our childrens’ future is sugar; especially sugar found in fizzy drinks (soda in the US) and fruit juice.
Let’s say a child needs 1800 calories a day and is in energy balance.
She starts secondary school and starts a 2 miles(!) return walk to school - roughly 40 minutes of exercise. This means she needs an extra 100 calories, (roughly: 150lb adult burns 100 cals/mile - 75lb child therefore needs 50 cals/mile) so her mum feels justified in allowing her an extra can of Coke (or the equivalent in fruit juice) because of all that exercise. There are 142 cals in 330ml either Coke or fruit juice, and she burns 100 of them, leaving 42 in excess. Multiply that by 190 (average days in a school year) then by 5 years (age 11 to 16) will translate to her carrying an extra 11.4lbs of abdominal fat she does’t need. I think I’ve got the above right, but feel free to correct me if I’m wrong. (By the way, that energy she needs for the daily walk translates to just 2 teaspoons of sugar!)
And that’s with just ONE can per day! Factor in all the other cans, bags of sweets and all the other sugary junk that’s in just about everything and you can see where the problem lies. An 11.4lb excess at 16 looks pitifully small then.
When I was a child I had no fizzy drinks whatsoever (saving Christmas) and fruit juice wasn’t available. I remember the ‘Corona’ wagon that you used to book your order with (and who gave you your deposit back on empties), but we never bothered. I go into any supermarket now and look with slack jawed astonishment and horror at the serried rows of sugary junk waiting to assault our kids’ unfinished livers.
Repeating what I’ve said before; lack of exercise cannot explain tiny children with non alcoholic fatty liver disease (NAFLD) and even 5 year olds with non alcoholic cirrhosis if you can believe that! Even if they don’t get sick and are merely(?) overweight it’s a short haul from there to the late teens and then alcohol is added to the load on a damaged liver. Google ‘alcoholic cirrhosis in young adults’ and there are well over a million hits. Though I have yet to see the correlation to sugar induced NAFLD it must undoubtably be there! Adults lay down liver fat very differently than children - Here’s a snippet a from a PubMed article on childhood NAFLD:
‘Excessive nutrients cannot be stored in the adipose tissue and overflow elsewhere, mainly to the muscle tissue and liver. Fat deposition in both sites enhances insulin resistance and further deposition of fats in a vicious manner’.
Fructose’s metabolic pathway.
The liver is the only organ that can metabolise fructose, and sugar is 50% fructose. The other half, glucose, can be utilised by every other cell in the body. When the liver can’t cope with fructose (or alcohol) overload it lays down fat within itself and that’s a precursor to cirrhosis.
So, the bottom line for me will be protecting my 9 and 10 year old sons’ metabolisms (and their teeth) by eliminating (tall order) or at least reducing to a minimum sugar from their diet. I think it might be a good idea for all of us.