I don't agree with your comparison of obesity and homosexuality though. Nor can I find anything about obesity being an abonimation to God as I see about homosexuality. It's quite specific.
Everytime we sit down and have a meal we pray to God and give him thanks. Jesus asks of God "give us this day our daily bread". The scriptures are clear that food has a sacred quality to it because it is so intristically tied to continuation of life. Likewise, sex is tied to the continuation and production of life.
Food exists to provide the sacred body that God has given us with sustenance, it exists to sustain our bodies so that we can continue to carry on God's gift of life and function to the best of our abilities.
Food is pleasurable in many instances to our taste buds, in the same sense, sex appeases our senses. However, to indulge in sex or to indulge in food for the purpose of pleasure, while disregarding the purpose of sex, pro-creation, or disregarding the purpose of food, sustenance, is to misuse and pervert those gifts which God has given us. This is what Augustine has labelled as evil, the perversion or degeneration of something that is good.
When we over indulge in food, or eat the wrong kinds of food to appease our senses, the harm to our bodies (agains which are meant to be vessels of holiness) is obvious. Being seriously overweight can lead to numerous health problems, and the risk of heart attack and heart disease is significantly increased. Likewise, we are told that the homosexual lifestyle is dangerous to the body, posing a signigicant risk of disease.
The Bible makes no commentary on obesity, clearly because when it was written being dangerously overweight was not an issue. But it is clearly an abomination in the same sense as homosexuality because it is a misue of the body. People in third world nations are dying because they don't have enough food to eat, yet people in the developed world are dying because they are eating far too much, and far too much of the wrong things in excess.
I think I have drawn some very important parallels. Please do not subvert my argument with the claim that I am subverting a discussion of homosexuality. I am simply using the same logic and arguments which have been used against homosexuality, and seeing that many of the same points would apply to being overweight.