Obesity, we're told by th' />

Finally, an expert on human nutrition brave enough to tell us what we don't want to hear - it's our fault if we're fat.

Obesity, we're told by those well-meaning groups formed to fight it, is a complex issue caused by environmental or hormonal or psychological issues. Individuals are not to blame and should not be discriminated against, they opine. More money should be poured into DHBs to help them. They mustn't be persecuted. It's not their fault they can't walk past a patisserie without wolfing down pies and doughnuts.

Then along came John Birkbeck of Massey University, adjunct professor in human nutrition, who told journalist Geraldine Johns in this newspaper: "You can't get over-fat without eating more calories than you expend."

And this: "You do not see fat people in concentration camps. Why? Because they get hardly anything to eat and they have to do a lot of work."

National MP Maurice Williamson must be muttering into his whiskers. Two years ago he was pilloried for saying virtually the same thing: "If some people can't lose weight no matter what, how come there were no fat people in Nazi concentration camps?"

Williamson was correct then, and Birkbeck's correct now, but of course he's already angered the Eating Difficulties Education Network. Spokeswoman Maree Burns called Birkbeck's comments "flagrant, inappropriate, intolerant and offensive", adding "shaming and blaming people has never been effective".

But actually it has. Look what we do to smokers. We treat them like lepers, forcing them out into the street, away from bars and restaurants. Two decades ago it was acceptable to smoke on planes, in offices and pubs. Now everywhere is proudly a smokefree environment.

If it's acceptable to shame and sin tax anyone addicted to nicotine and alcohol, why not do the same to those addicted to food? "This is a pizza/pie/burger/fizzy-drink free zone". I doubt it - remember the outcry when Air New Zealand did away with meals on its one-hour flights? I watch fat people in the Koru lounge piling up their plates with "free" food, then going back for more and I wonder if they are really starving, or just plain greedy.

Over-fat people eat too much for numerous reasons. They're unhappy, unloved, lazy, don't care, love food, are weak-willed, can't cook properly, but they're not obese for cultural reasons, or because they're big-boned, have hormone problems, or other "it's not my fault" excuses. Thankfully, we all come in different sizes - large, petite, slim, solid - but basically obesity is caused by eating too much food.

As Birkbeck stated, our society is in danger of accepting over-fatness as the norm. These days, it's the skinny, flat-chested girls who are shamed on television modelling competitions. She must be anorexic, we gasp, if we see a hip bone or a rib.

I don't mind if people are overweight. I don't judge their personality by their size, but I care if they're unhappy. I feel sorry for fat children if they're bullied at school - they'll feel miserable, be reluctant to do sport, eat more to compensate and so the vicious cycle begins until they become obese adults.

But molly-coddling won't help. Tough love works with treating other addictions - we should use it on food addictions.

Ban junk food at state-funded schools; don't give in just because the dairy over the road sells pies - that was a cop-out by National.

Reintroduce compulsory, and competitive, sport in schools, even if it means walking between lamp-posts for the fat kids. Teach them basic cooking skills, some food nutrition, like sucking on a bottle of water all day WON'T lose weight, and 99 per cent fat-free just means it's chock-full of sugar.

Campaigners like Robyn Toomath are right to warn our public health system won't cope with disease caused by fat New Zealanders. More than half of you are eating yourselves to death and the rest of us are paying for it.

So how about some incentives for losing weight? If you're a smoker you pay more for life insurance because you're a greater risk. But I don't get any discount on my ACC levies or my medical insurance despite my BMI being 22.

If I fly with excess baggage I'm charged extra, yet the gut from the guy next to me could be rolling over the armrest into my seat, so why shouldn't he pay extra for his 130kg of bodyweight?

Yes, I know why, because it would hurt his feelings. He has every right to be a big, fat slob. And people like me who don't eat more than we need should just shut up and pay.