Fermentation Guide & and little yellow flag

Fermentation is basically a way to produce NAD+.  Nad-plus is an improtant ingredient/fuel for energy production when a cell can't get access to oxygen.

Some cells can switch to this auxiliary 'fuel system' that produces that valuable NAD+, which helps extract energy from glucose.

Also note, there are tworking kinds of fermentation.  One that makes a burning sensation. In your muscles when they work hard, and the other that results in alcohol formation.