Small business owners have been encouraged to take on older workers following a study showing that employing staff over 60 years old can lead to a business being more profitable.

Researchers from Lancaster University Management School conducted research at over 400 McDonald's chains and found that restaurants that employ older staff have greater customer satisfaction and profit levels.

"The research clearly demonstrates the very real business value of recruiting an age-diverse workforce," said Professor Paul Sparrow of Lancaster University.

The study also found that younger staff respond positively to the work ethic and face-to face customer skills of older staff.