Tony Franklin entered a betting shop in northwest London one morning this month and paid 300 pounds, or around $400, into a gambling machine — and lost that money within 16 minutes.

Then he paid in another 300 pounds. Then a further 1,000 pounds six minutes later. And 20 minutes after that, a final 1,000 pounds.

Within 42 minutes, Franklin had lost 2,600 pounds, the latest relapse in a decadeslong gambling addiction that he reckons has cost him more than 1 million pounds, his marriage, several jobs and his relationship with his three children.

“I just don’t know why I go in, and this is the problem,” Franklin, 46, said a few hours later. “You know you’re going to lose.”

Franklin has been trying to quit gambling for years. What usually drags him back in is a particular kind of gambling machine, known as a fixed-odds betting terminal, that lies at the heart of a bitter debate about the future of British gambling. Campaigners and some researchers say the machine is an unusually addictive form of gambling that is sucking billions out of Britain’s poorest communities, and some hope it will be banned after a government review next month.