In the excellent BBC series about the history of design (The Genius of Design), chairs played a large role. Perhaps a fifth of the show is about them, far more than any other product. Yet I rarely use them and own only a few. I sit while socializing but otherwise usually work reclining (on a bed or in a rocking chair) or standing up. Long ago I discovered that if I stand a lot I sleep better. Since then I've spent a lot of time on my feet for someone whose job doesn't require it.

My self-experimental discoveries led me to avoid about 99% of the food sold in a typical store - granola, cake mixes, flour, rice, breakfast cereals, and so on. Most of what I avoid is carbohydrate. Just as we are pushed to sit in chairs, we are pushed to eat carbohydrate. I don't think carbs cause obesity - it's more complicated than that - but they raise blood sugar (making diabetes more likely) and rarely supply essential fats. They are also poor sources of microbes, which I'm sure you need to eat.