A group of right-wing Conservative MPs has warned that too many young people are taking university arts courses.
'Barely half' of students were doing jobs which needed a degree
Tory leader David Cameron has said anyone who thinks they can gain from a degree should have the chance to go.
But the Cornerstone group of MPs said studying traditional arts subjects could make graduates worse off, with growing numbers "not benefiting".
However, the government says that university is still a "worthwhile investment" for students.
'Passed the point'
MP Julian Brazier, who wrote a paper for the Cornerstone group, said: "Everyone with the educational attainment to benefit from a degree course should have the opportunity to go to university - as David Cameron has rightly said."
However, participation had "already passed that point" , he added.
Cornerstone argued that vocational courses such as media studies gave a bigger boost to job prospects.
Mr Brazier said "barely half" of those who had entered university in recent years had completed their degrees "and followed careers for which a degree is even a norm, let alone a requirement".
Many taking arts subjects were "likely to make a substantial financial loss out of their time at university", given the costs involved.
The paper cited research showing that one in three students recently entering university either dropped out of their courses, failed to get work or settled for non-graduate jobs.
A Swansea University report published last year found graduates could expect to earn £150,000 more over their lifetimes than those with just A-levels - £250,000 less than previously estimated by ministers.
Researchers said some subjects - such as the arts - could even mean losses, when fees and living costs were taken into account.
The report, based on the British Labour Survey, blamed the increase in student numbers for narrowing the earnings gap.
But the government said that the discrepancy between earnings figures was partly due to the different ways in which they had been calculated.