Legendary quarterback Tom Brady says he's never had a cup of coffee "or anything like that." That's just as well. In early March of this year, he had knee surgery and is rehabbing it in order to be ready for summer training camp.

It turns out an unrecognized issue that impacts surgery is caffeine withdrawal, which many patients go through leading up to, during, and after an operation.

A study in the journal Food and Chemical Toxicology says that when caffeine-loving patients can't eat or drink anything for hours before a procedure, it can trigger withdrawal symptoms such as drowsiness, difficulty concentrating, and intense headaches.

And those reactions can complicate treatment and even extend hospital stays. Withdrawal also can increase the risk of delirium in intubated emergency room patients.

Around 90% of adults consume caffeine regularly, and get the remarkable health-boosting benefits that include helping prevent diabetes and lowering inflammation.

But caffeine withdrawal symptoms can pop up three hours after your last dose and persist for up to nine days.

The lead author of the study summed up the researchers' conclusions: "This is a no-brainer," he said. "We have everything we need to supplement patients as needed and prevent these symptoms. But first we have to start paying better attention."

Let your doctor know if you're a caffeine aficionado well before you head into the operating room for any planned procedure.

Ask if caffeine supplements or even a cup of joe as you wake up after surgery might be a smart move (with your physician’s approval) so you can avoid the complications of withdrawal.