Students who take gap years are more likely to smoke weed, "engage in risky behaviour" and earn less than those who go to university immediately after sitting their A-levels, a study has claimed.

The research, funded by the government, revealed less than 20% of students who progressed straight to university had smoked cannabis, compared to 30% of those who took gap years. The report by the Centre for Analysis of Youth Transitions (CAYT) also suggested gap year takers have "significantly lower wages" than those who don't opt for a year out.

"[This is] simply because they have fewer years after graduation during which they can reap the returns to their investment in human capital," the report says.

The CAYT researchers followed the lives of 16,000 people born between 1989 and 1990m and one group born in a particular week in April 1970. The "Gap-year takers: Uptake, trends and long term outcomes" publication studied the long-term implications of taking a gap-year between school or college and university.

The report added there was "some evidence that those who go straight to university are more likely to have studied science, technology, maths and science subjects at AS- and A-level".

Of those who deferred university, 20% admitted playing truant from school before they were 16, this rose to 30% for those who didn't attend university at all but dropped to 10% for students who did not take a gap year.

"The decision to take a gap year.. appears to have negative consequences for a range of outcomes observed later in life," the report concludes. "[But] this report does not conclude individuals should necessarily be discouraged from taking a gap year."