I spent about 45000 for the 15 months. Some places cost less, some places cost more especially if there is some specific activities involved such as safari, diving, cruises (which i took to antarctica) . there are lots of activities which are free too - trekking in Patagonia and volcanoes hike.. so, it was pretty much about balance between frugality and luxury.
I was lucky as only one case of bad stomach in Tanzania which lasted for a while. Fell ill due to extreme hot weather and rough travelling conditons in jeruselem and Fez, Morocco. Either I self medicate or go to he pharmacy.
Bed ridden once for a few days in Patagonia when I fell face down like a pole.. left me with a cracked bleeding lips, swollen like angelina Jolie, brusied nose and cuts over the face.. self pity seeped in and was so miserable, really wish to have friends and family around at that time
Hygiene wise - honestly, i dont think of it.. eat first then worry later

Last thing - Like our mums always say " drink more water"