As an experiment today, I consumed a Snickers bar, a Lemon Ice Tea, and then indulged in a sugary lemon soda soft drink an hour later. For the next few hours, I found my fluency was adversely affected by the caffeine and high sugar content. I’m convinced this dopamine surge really affects my fluency because on a normal day, I’ll drink one decaf coffee in the morning and for the rest of the day I’ll drink herbal tea (zero caffeine), and have zero sugary treats.