Almost 450,000 teenagers are thought to have engaged in online casino-style gambling, having been lured through video games.
Players can gamble "skins"—virtual in-game items which can be bought and sold for real money—and some young people are losing thousands of dollars in doing so.
The scale of the problem was revealed by pollster Ipsos MORI, which found that 10 per cent of 13-18 year-olds surveyed admitted gambling on unregulated casino sites and other betting games. This percentage would be equivalent to just under 449,000 teenagers.
Using skins instead of actual currency allows websites to circumvent the law which prohibits under-18s from online gambling.
Parenting website Parent Zone, which commissioned the survey, says the loophole which permits this activity needs to be closed.
Giles Milton, Parent Zone's head of content, said: "It is gambling and children should not be gambling online. Parents need to understand what their children are doing with their money."
Various teenagers spoke to Parent Zone about their experiences of gambling.
One 15-year-old had amassed a collection of skins worth more than $2000. To add to it, he tried a gambling website and is now "really addicted" to it.
Another, 13, said it was easy to lose "loads of money" on the websites, adding: "It's basically just gambling, they just cover it up".
The poll found that almost half of teenagers know how to bypass age verification checks online.
It added that parents need to be more aware of the issue and how their children are spending money online.
The website called on policy makers to launch an independent inquiry into new forms of online gambling, and work with gambling websites to prevent underage users from participating.
Never miss another Spirit-filled news story again. Get Charisma's best content delivered right to your inbox! Click here to subscribe to the Charisma News newsletter.
Three Summer Deals from Charisma: