Junk-food pregnancy diet raises cancer risk
Published 20/04/2010 | 05:00
A DIET laden in fat during pregnancy may lead to an increased risk of breast cancer that is passed down generations, say scientists.
Pregnant women who dine on junk food could unwittingly be risking the future health of not only their daughters but also their grand-daughters, research suggests.
The US study, conducted on rats, provides further evidence that environmental factors can cause inheritable genetic changes. Scientists believe the findings have an important message for humans.
"The implications from this study are that pregnant mothers need to eat a well-balanced diet because they may be affecting the future health of their daughters and granddaughters," said lead researcher Sonia de Assis, from Georgetown University in Washington DC.
The researchers fed a group of mother rats either a high-fat or normal diet and looked at what happened to their offspring and the subsequent generation.
They found that not only did a high-fat diet increase the risk of daughters having breast cancer, but also granddaughters.
The risk was not only passed on by daughters but also sons.
Daughters of male and female rats who both had fat-consuming mothers had an 80pc chance of developing breast cancer.
But the risk fell to 69pc if the mother of one parent -- either father or mother -- had a high-fat diet and the other grandmother had a normal diet during pregnancy.
Granddaughters of grandmother rats given a normal diet had a 50pc chance of developing breast cancer. The scientists cannot explain how diet influences breast cancer risk down two generations but believe "epigenetic" factors are involved. These are genetic changes caused by the environment that can potentially be passed on to future generations of offspring.
In the rats, something linked to diet made it more likely for "terminal end buds" -- structures where tumours can develop -- to appear in the breast tissue of daughters and granddaughters.
"That is our theory, but we really don't know how it is happening, just yet," said Dr De Assis, who presented the findings at the American Association for Cancer Research annual meeting in Washington DC.
Meanwhile, a separate British survey has found that most people have no idea that their spare tyre is putting them at increased risk of cancer, diabetes and heart disease, a poll found yesterday.
Excess weight around the middle generates oestrogen and excess chemicals in the stomach, which put people at higher risk of killer diseases.
Yet 97pc of people are unaware of a link despite 71pc of those surveyed saying they had a spare tyre.
When asked to pinpoint the waist measurement that causes them to tip over into being at risk, more than half of people overestimated it. Women are at risk of type-two diabetes and heart disease if their waist measures more than 80cm (31.5in) while men are at risk at more than 94cm (37in).
Yesterday's survey of more than 2,000 people was commissioned by Diabetes UK, Cancer Research UK and the British Heart Foundation (BHF).
The charities have joined forces to launch a new Active Fat campaign to raise awareness of the dangers of carrying excess weight around the middle.
Mike Knapton, associate medical director for the BHF, said: "That 'harmless' spare tyre around your waist is actually a major health hazard."
While you might be relaxing at home, "your fat cells are working overtime", he said.