Dutch scientists say by eating crisps or chips on a daily basis a woman could be doubling her risk of ovarian or womb cancer.
This is because chips and crisps and food which is browned or burned by cooking contains the chemical acrylamide.
Fried chips, crisps and overdone toast are among foods which contain the highest levels of acrylamide.
The chemical occurs naturally in cooked food and is also present in roasted, grilled and barbecued meat, bread and even breakfast cereals.
Acrylamide was linked five years ago in other research to cancers and this latest study is suggesting a link with two cancers in women; however a study published in 2005 found no evidence that acrylamide increased the risk of breast cancer.
For the study the researchers from the University of Maastricht questioned 120,000 people, 62,000 of whom were women, on their eating habits, and found that women who ate more acrylamide appeared more at risk.
Experts however say other factors could be involved and are urging women not to panic; but they say overcooking when baking, frying or toasting carbohydrate-rich foods should be avoided.
They also say it is virtually impossible to eliminate the chemical from diets.
The researchers followed the volunteers for 11 years after their initial questionnaire, during which time 327 of them developed endometrial (womb) cancer, and 300 developed ovarian cancer.
An analysis revealed that those who ate 40 micrograms of acrylamide a day, the equivalent to half a pack of biscuits, a portion of chips or a single packet of crisps - were twice as likely to fall prey to these cancers compared with those who ate much less acrylamide.
The researchers say their results need to be confirmed by other research.