In theory, caffeine blocks the effects of diamine oxidase (DAO), which is an important histamine degrading agent, which blocks the cleaning up of histamines from your system. To avoid the caffeine content, switch to a quality decaf.

Does caffeine affect DAO?

Caffeine may block the effects of diamine oxidase (DAO), an important histamine degrading enzyme, while mold can cause your body's immune system to go wild.

Does caffeine increase histamine?

Histamine level significantly increased beginning 30 min after caffeine administration and remained elevated for at least 140 min.