There's a big difference between telling people obesity is hunky dory and supporting the obese in a way that isn't as likely to lead to self loathing etc.
You tell them that then. It was not too long ago that I was ranting about the preposterousness of that one particularly obese woman squaring off against a doctor over whether the term obese should be banned because it made obese people feel bad, or when I was ranting about the malicious delusions of the fat acceptance movement that preached the Darwin-award worthy notion that being obese is not a massive health risk and a gratuitous waste of resources and healthcare, or when I was ranting about how the fat acceptance movement reached the point where they were saying things like people calling them fat is literally as bad as racism.
No one should have to support the obese because obesity is not something that should be supported. Help people get fit and have the NHS try to keep them alive in an uphill battle only getting worse with each and every extra large portion of fries. 28% of British children are now obese too. Nothing disgusts me more than a parent who feeds their child troughs of fast food; it's neglect. Feel guilt and shame for an unhealthy lifestyle because it is an unhealthy lifestyle.
Much can be done to aid the obese, for one stop the promotion of food adverts that sexualize gluttony and those "calorie count" diets that promise freedom from fat yet deliver only malnutrition and dangerous weight loss, for another spend gratuitous amounts of money trying to persuade people to be more proactive against the face of their sedentary lives and promote healthy eating (at this point obese people are such a strain on this country that anything that costs lest than £5,000,000,000 is a net profit). But at the end of the day if you have working limbs and you get obese and you feel shame when confronted with your obesity you should try to change yourself instead of forcing the world to change around you. The obesity problem is already beyond the point where the majority of the UK is obese, shame is what you feel when you personally make foolish decisions; it is not something to run away from when you eat yourself to an early grave, you confront it and better yourself.