The prolonged traumatic, or “chronic toxic,” stress that most people have been experiencing throughout the pandemic makes it more difficult to keep desires in check, and it in turn promotes illogical pleasure-seeking, said Dr. Robert Lustig, a professor emeritus of pediatric endocrinology at the University of California, San Francisco, and author of “Metabolical.” In scientific terms: When brains are flooded with the stress hormone cortisol on a long-term basis, it inhibits the function of the prefrontal cortex, leading to excessive activation of the “reward center” of the brain — triggering the excessive baking, drinking, smoking and shopping that filled the idle hours of 2020.

“Dopamine is the reward neurotransmitter. It is held in check by the prefrontal cortex. When that inhibition is released, the reward center looks for hedonic stimuli,” Lustig said. “Those can be chemical — cocaine, heroin, nicotine, alcohol, sugar — or behavioral — shopping, gambling, internet gaming, social media, pornography.”

Take the beloved carbohydrate sugar. Early in the pandemic, a baking frenzy swept the country, offering both a relatively accessible quarantine hobby and a constant supply of carbs. Like hand sanitizer and toilet paper, flour and yeast went from lowly supermarket staples to hot-ticket items quickly nabbed from store shelves.