Most of the fiber is in the skin[1]. There's some debate about if it also contains more pesticides etc. but you can grow your own or buy organic. It is true that you want to keep your potatoes in the cool and dark, since when they green they become more toxic[2].
I buy organic potatoes but I don't think everything natural is good, for instance high arsenic levels in rice, even more so in brown rice.
Concerning the potatoes there's some kind of preservative they put on the potatoes to inhibit germination (on non-organic potatoes). They used Chlorpropham but that seems to be prohibited since 2020 (in the EU?), now they use Maleic hydrazide but I don't know about any health issues.
Concerning the potatoes there's some kind of preservative they put on the potatoes to inhibit germination (on non-organic potatoes). They used Chlorpropham but that seems to be prohibited since 2020 (in the EU?), now they use Maleic hydrazide but I don't know about any health issues.