Your run-of-the-mill shoe stank might not pose much of a survival threat, but trench foot certainly will; baking soda is great at absorbing the moisture that might otherwise literally cause your feet to rot off your legs. As for the health of your teeth -- it will be pretty hard to get through your day's rations of homemade jerky and hardtack without some high-quality chompers. And you certainly don't want to rely on that pesky fluoride that will "kill your brain over time" (um, what?).
To me, the best option is to store emergency food. How much? If you have none, store enough for a few days. If you have enough for a few days, get enough for a week. How much you store depends on what time frame you think you're at risk for having to be completely independent. The early settlers of the southwest liked to store enough food for a whole year and still do to this day!