Fibbers should also refrain from verbal tirades and if they smile, make sure they also use their eyes.
A professor of psychology will today issue advice on how to spot liars in interviews, but it could equally help those seeking to pull the wool over the eyes of prospective employers.
Adrian Furnham, of University College London, encourages managers to note any "mismatch" between what applicants say and how they say it.
Professor Furnham will tell a seminar at the Institute of Personnel and Development's recruitment and selection conference that most adults are experienced liars. However, it is important to be aware of the signs: "The ability to detect falsity in facial expression or manner of speech can hold the key to reducing the likelihood of a candidate slipping through the net by the most fantastic deceit."
He suggests some tell-tale signs which might be more difficult to conceal except by the most practised liars such as sweating, pupil dilation and blushing.
"Most of us are 'torso liars' - we can lie with our upper-body - but we are not so good with the lower halves of our bodies," he says.
He concedes that there will be a difference between the nationalities and his advice is aimed at the detection of the British liar.
The Italians will be more "gesture-laden", a trait which in this country might be interpreted as sign that the interviewee is dissembling.
The Chinese will have different "eye-contact patterns", will look rather stiff compared to the British and may even look frightened. However that may be simply an expression of politeness and deference, according to Professor Furnham.
While most people tend to fib a lot in everyday life - lies of both omission and commission - interviewees are generally truthful, he says. Yet many people are tempted into mild deceits as they try to sell themselves.
"Lying at interviews can take many forms and has different levels. There is the tendency to attribute desirable characteristics; there is the tendency to deny undesirable characteristics. Then there are the self-deceivers - those who believe their own positive self-reports - and lastly those who deliberately seek to fool the interviewer through lies.
"Making the wrong decision remains every recruiter's nightmare," he adds.
The tendency to embellish the truth at interviews has tended to weaken their objectivity as a recruitment tool, the Professor believes.
Graeme Wright, director of media and research at Park Human Resources, will tell another IPD seminar that traditional selection techniques such as the face-to-face interview are on the brink of decline.
In America, leading employers conduct initial dialogue with prospective recruits on the Internet.
By 2004, some 66 per cent of all homes in Britain will have personal computers, a fact which will revolutionise the world of recruitment, according to Mr Wright.