The price of break can start going up even before money is printed. World reserve currency status is due to the fact that historically US Dollar was a very safe and reliable storage of wealth. As soon as talks of printing more money start circulating, people outside of US will start selling USD and buying EUR/Chinese Yuan/Bitcoins/local currency. Due to that, US Dollar exhchange rate can collapse and price of bread will definitely go up.
There is some flexibility - trust in USD is still very strong and US can print quite a bit before negative cycle kicks in but it defintely could not print as much as needed to make everyone rich.