Reza Jafery has been something of a workaholic since he was in first grade. Whenever he was assigned homework, he'd head straight for the library at the end of the day and would finish it before going home. Attending an elite high school in Dubai further spurred his desire to be successful, as did his hard-working parents. But he was driven more by compulsion than a love of learning, and became anxious if he didn't have something in his sights to accomplish.

"I felt I had to reach particular milestones by a certain age or else I wasn't successful," says 27-year-old Jafery. "I told myself that I wouldn't have to work as hard once I was successful, and that I'd be happy. But I hadn't defined what success was and life was just a constant race."

Now living in Los Angeles, the self-professed productivity junkie has two jobs: he is the blockchain lead for a cryptocurrency company and the founder of a digital agency. Jafery works long hours "90% of the time", which means working until midnight and at weekends and getting just five hours sleep for a few weeks at a stretch.

According to the chief director of the Center for BrainHealth at the University of Texas at Dallas, Dr Sandra Chapman, the brain can become addicted to productivity just as it can to more familiar sources of addiction, such as drugs, gambling, eating or shopping.

"A person might crave the recognition their work gives them, or the salary increases they get," says Chapman. "The problem is that just like all addictions, over time a person needs more and more to be satisfied and then it starts to work against you. Withdrawal symptoms include increased anxiety, depression and fear."

Read article from BBC Worklife here