New research suggests that a daily helping of cheese could increase the risk of bladder cancer.
Eating more than 53g – roughly the same size as a small chocolate bar – raises the chance of the disease by 50 per cent.
On the other hand, a daily portion of olive oil, can more than halve the risk of getting the disease.
Researchers set out to discover if saturated fats, such as those found in meat and dairy products, made cancer more likely and healthier fats, such as olive oil, offered some protection.
They studied the eating habits of 200 bladder cancer victims and compared them with 386 volunteers who had not developed tumours.
The results showed eating cheese had little effect unless the amount exceeded 53g a day. After that, the risk went up by more than half.
But the Dutch and Belgian researchers stressed the numbers of people in the study may be too small to conclude that cheese is a major health threat and called for further investigations to verify their findings.
Other foods, such as fish, chicken, eggs and margarine, appeared to have little effect.
"We found a potentially protective effect from a high intake of olive oil and a suggestive increased risk from high cheese consumption," the Daily Mail quoted the researchers as saying.
The study was published in the European Journal of Cancer.