It's a working-class staple. And it could be priced out of the market by government efforts to make bakeries change from wood-fired ovens to other fuels to curb air pollution.

Bread — and the lack thereof — plays a role in many corners of the world facing a crisis, from Israel and Gaza to Ukraine to Afghanistan to Sudan.

Last year, the region imported more than 36 million metric tons of wheat, mostly from Russia and Ukraine. The concern is that Russia's war in Ukraine could disrupt supplies and drive up prices.

Yes, Ireland has a legal definition for bread. And the nation's Supreme Court said Subway's bread has too much sugar to satisfy it.