For the study, scientists at the University of California, San Diego (UCSD) examined survey responses from over 4,500 children aged between 11 and 15 from 21 communities across the United States.
Participants were asked about their substance use in the past month, including whether their parents found out about it. They also completed a questionnaire on how often their parents knew their whereabouts or plans for the day.
Overall, 3.6 per cent of kids said they had used alcohol or drugs in the past month, the study found.
Researchers calculated that substance use would have been 40 per cent higher in the study group as a whole if children did not have second thoughts about their behaviour due to fear of their parents' monitoring.
Professor William Pelham, lead researcher and an assistant adjunct professor of psychiatry at UCSD, said the findings suggest that monitoring teenagers can reduce their chances of using alcohol or drugs simply by making them think twice, whether or not parents succeed in catching them.
"Some parents think drinking or using drugs is something that kids are just going to do, no matter what," he said. "But that's not true. Parents can make a difference."
A study published last month by the World Health Organisation (WHO) found that more than half of children in England, Scotland and Wales had drunk alcohol by the age of 13.
More than a third of boys (35 per cent) and girls (34 per cent) had drunk alcohol by the age of 11, according to the study, while 40 per cent of girls in England and Scotland had vaped before the age of 15.
Dr Katherine Severi, chief executive of the Institute of Alcohol Studies, said youth drinking is in decline overall, but added that “the UK is one of the heaviest drinking nations in the world”.
She said: “People tend to have this perception that introducing children to moderate drinking is a good way of teaching them safer drinking habits. This is untrue. The earlier a child drinks, the more likely they are to develop problems with alcohol in later life.”