Decaffeinated tea is NOT caffeine-free. The decaffeination process leaves a minute amount of caffeine in the leaf. By law, tea labeled as “decaffeinated” must have less than 2.5 percent of its original caffeine level, which usually equates to less than 2 mg per cup.

Why decaf tea is bad for you?

It's important to note that decaf tea may still contain very low caffeine levels depending on how its produced — more on that in a minute. Too much caffeine can interrupt the sleep cycle and cause side effects including nausea, upset stomach, aggravate acid reflux, and trigger migraines.

Are decaf teas really decaf?

Let's start simple: Decaffeinated (decaf for short) tea is tea leaves that have undergone a process that removes most of the caffeine. By law, tea labelled “decaffeinated” must contain less than 2.5% of its original caffeine. Because of this law and limitations in the process, no decaf tea is actually caffeine free.