(Poor 3rd worlders pay more for basic food if not subsidised)

https://www.theguardian.com/sustainable-business/agricultural-subsidies-reform-government-support

China has far higher farm subsidies than US. The yanks sure produce cheaper corn than China.

Hindu dairy garmers are threatened by milk powder imports

http://www.stuff.co.nz/business/farming/3972942/Protests-against-NZ-milk-in-India

http://www.baif.org.in/doc/Livestock_Devt/WTO%20Challenges%20for%20Indian%20Dairyl%20Farmers.doc

Hindu  farmers dumped tomatoes in the street because of imports from china and US

http://devinder-sharma.blogspot.hk/2014/10/while-indian-farmers-are-forced-to-dump.html#!/2014/10/while-indian-farmers-are-forced-to-dump.html

PPPee GDP only applies to some sectors like truely modern medical services provided the personels are well trained and low cost. No such things like PPPee prices for commodities, computer equipements, weapons..and what nots...

The average poor 3rd worlders definitely spend a lot more on basic food than chemotherapy.