People who ignore expiry dates on food to save money in the recession run the risk of being exposed to the dangerous listeria bacteria, according to an all-Ireland food safety organisation.

Safe Food, a North-South body responsible for the promotion of food safety, is concerned that the return of more penny-pinching attitudes towards groceries will put people at serious risk of illness.

The body warns that cases of human listeriosis, one of the most serious food-borne bacterial infections, are on the increase across Europe, including Ireland.

This is backed up by the most recent available figures which show that, in 2007 21 listeriosis cases (0.5 per 100,000) were reported in the Republic Of Ireland, three times the number of notified cases in 2006.

"People want to stretch things out a bit more. The danger is if you are a bit older or you have an underlying medical condition, or you are very young, you may be more susceptible to these types of food poisoning germs than you would be if you're in the middle point of your life and otherwise healthy," warned Dr David McCleery a microbiologist with Safe Food.

"The 'use-by' date is the date that food can be used up to, provided it has been stored as described on the label.

The 'use-by' date is not to be confused with the 'best before' date which provides an indication of the quality of the food. It is okay to eat food after a 'best before' date but never after a 'use-by' date," said McCleery.