Chicken liver products used in home cooking are linked to campylobacter food poisoning, experts say.

The Food Standards Agency has urged home cooks and caterers to ensure that their chicken liver pieces are cooked thoroughly before serving, after the Health Protection Agency discovered that 11 of the 15 outbreaks of campylobacter were linked to liver.

Most outbreaks of the disease between 2005 and 2010 occurred at catering premises such as restaurants or hotels, where liver products were cooked on-site instead of being in a ready made condition.

This news comes after a representative from Foods for Life claimed that the five-a-day guideline for fruit and vegetable consumption does not adequately negate peoples' current stress levels.

Yvonne Bishop-Weston, nutrition consultant at Foods For Life, said: "The government message is confusing, because there is no clear evidence anywhere that says that five-a-day is perfect for preventing disease. We don't recommend five-a-day, we recommend eight-a-day in our clinics."