why are there still so many people overweight despite the current fitness craze ?   well , there are certain factors that effect people's size and weight .   what are they ?   one study said that low-income groups have a higher percentage of over-weight people than higher income families .   why ?   the survey said that the low , income groups eat more junk food on a daily basis .   that makes sense . Probably less time to make dinner and the junk food is cheaper .   and junk food contains lots of fat and oil . There is one final reason why so many people are fat .   what's that ? 