as someone who actually does have a thyroid condition, people using that as an excuse for why they're fat grinds my gears like nothing else. yes, it can make it harder for you to lose weight. no, it won't make you obese. a good portion of my family also has thyroid issues and not one of them is obese. overweight maybe, but not obese. and if you treat your thyroid problem (which you should because it can seriously fuck up your body in a lot of ways if you don't), then a lot of the weight you've gained will come back off.