Lactose intolerance is the inability to digest a sugar called lactose
that is found in milk and dairy products.
Normally when a person eats something containing lactose, an
enzyme in the small intestine called lactase breaks
down lactose into simpler sugar forms called glucose and galactose.
These simple sugars are then easily absorbed into the
bloodstream and turned into energy — fuel for our bodies.
People with lactose intolerance do not produce enough of the
lactase enzyme to break down lactose. Instead, undigested
lactose sits in the gut and gets broken down by bacteria,
causing gas, bloating, stomach cramps, and diarrhea.