Anything can be overcome, humans can do anything (get out of poverty, convert to healthy living, run marathons, stop smoking....) yet the majority (of a huge sample size of humans) is stuck in their way, held down by environmental conditions and, if you will, by limits in the human condition or whatever. If it could be fixed by telling people to "try harder" they would have by now, no?

The answer is to alleviate the environmental conditions. You have mentioned in another post that you have benefitted from food stamps for a while (did I understand that right?), allowing you to eat healthy; other people need that and maybe a little additional help with food, housing and clothing (all of it basic human rights anyway and relatively cheap to provide for in a modern society) to reduce the pressure and higher order effects of not having that safety net.