Until I make the reluctant leap to join the Hive Mind (aka Facebook), I'll continue to update comment cut-and-paste texts for Ninja Commenting here on my blog. Here's the latest, which I'm using on general "why don't they just put down the donuts and take a walk" kind of fat hate threads, especially those targeted at "childhood obesity". I think it covers the basics for someone not already in the fat acceptance paradigm:
No one has ever developed a way to make fat people thin. Really. Everyone thinks that it's a very simple thing, but if that were so, wouldn't everyone be thin? No empirical study of weight loss shows more than a 5% long-term success rate for any weight loss method. That means that in five years, 95% of people not only re-gain all the weight they have lost, but generally end up approximately 3-10% heavier. That includes weight loss surgery patients.
The good news is that there are several studies showing that fat and unhealthy are NOT the same thing. Studies show that a person's level of exercise, regardless of how much they weigh, is the primary determinant of health. Genetic factors play a very high role as well. Stress (like in stigma and shaming) is a very important factor in developing many illnesses normally attributed to weight, but for some reason we blame the weight alone.
Trust me, kids know when they're fat. If they ever interact with our culture in America, they're not allowed to forget it. Shaming, bullying, and weight stigma have shockingly bad effects on health. For instance, eating disorders amongst kids younger than 12 have shot up in the last decade. Think about 9 year olds being hospitalized for anorexia before you condone weight-shaming in children. Childhood depression and other mood disorders have increased dramatically. Children who aren't even overweight for their age are developing a poor body image that will haunt them throughout their lives.
If you're interested in an alternative model for health instead of a fruitless pursuit of weight loss and panicked screaming about epidemics, (see the recent news from the federal health agencies that Americans actually haven't been getting any fatter for the last decade. Weight has not increased in any age category), use your search engine to look for HAES (Health at Every Size). You'll notice that a lot of the health specialists involved with promoting HAES are those on the front lines of eating disorder reasearch. They know that the old system of shaming and blaming is only going to do more harm.