Dr Malcolm McVicar, vice chancellor at the University of Central Lancashire, told staff in an internal newsletter to "refrain from comment or speculation" while the controversial courses are being scrutinised.

It comes after Dr Mike Eslea, a senior lecturer in psychology, blasted the university for adding complementary therapy courses in herbal medicine and acupuncture to its degree portfolio.

He described them as "quackery" and accused UCLan of running courses that would "severely damage" its reputation and have "no academic justification".

His comments have now led university bosses to review the legitimacy of the courses.

Dr McVicar, in the e-mailed newsletter, said: "Whilst the review is taking place, we need to recognise that there are students and staff studying and teaching on these courses which have satisfied the university's quality assurance procedures and been duly validated.

"I would therefore ask that colleagues would refrain from comment or speculation which would cause concern to these students and staff."

In his open letter to Dr McVicar, Mr Eslea wrote: "Although acupuncture and herbalism have been practised in one form or another for thousands of years, most of what we now call 'traditional' Chinese medicine is quite a recent invention."

He added: "It was concocted in the 1950s from a hotchpotch of folk myths and superstitions.

"Our hopes of being taken seriously as a research institution are being severely damaged by our association with such quackery, but now we are adding yet more bogus therapy to our portfolio."

A spokesman for UCLan said: "As a university we value and practise transparency and tolerance and welcome all academic viewpoints.

"With this in mind, and because we have received concerns from some colleagues as to whether the university should offer courses in homeopathy, herbalism and acupuncture, the university has set up a working group to review all the issues."

The working group, led by Eileen Martin, Pro Vice-Chancellor and Dean to the Faculty of Health, will report its findings and recommendations to the vice-chancellor later in the academic year.