2007-08-15 05:08:53
Mothers who eat junk food during pregnancy may be condemning their children to
crave the same diet, according to animal tests.
Royal Veterinary College researchers found that when pregnant rats were fed a
diet of biscuits, crisps and sweets, their babies ate more unhealthy food.
They said the British Journal of Nutrition study showed the rats' behaviour was
"programmed" in the womb.
Dieticians have stressed the importance of a balanced diet for mothers-to-be.
Future mothers should be aware that pregnancy and lactation are not the time to
over-indulge on fatty and sugary treats on the assumption that they are 'eating
for two'
Professor Neil Stickland
Royal Veterinary College
Scientists have already shown that, in humans, diet in early life can literally
shape your future, setting your risk of obesity and heart disease.
However, the latest research suggests that, in rats at least, eating too much
of the wrong food while carrying a child could be potentially harmful.
Chow or sweets
The female rats used in the Wellcome Trust funded research were either given a
balanced diet of "rat chow" - an unappealing but reasonably healthy diet - or
access to as many doughnuts, biscuits, muffins, sweets and crisps as they could
consume.
This diet was continued in some rats up to birth, and then during the
breastfeeding period until weaning.
Unsurprisingly, the rats given free rein to eat sweets consumed more food
overall.
Significantly, however, their babies showed marked differences in behaviour
compared with the offspring of chow-fed rats.
The young rats were split into different groups - some of those from chow-fed
mothers given nothing but their chow to eat, while the babies of junk-fed
mothers, and the rest from chow-fed mothers, were given a mixture of chow and
junk food to see which they chose.
Those in the chow-only group consumed the least food, while those from
healthy-eating mothers given junk food again were tempted to eat more.
These mechanisms are so finely tuned that I don't think we understand them yet
Fiona Ford
Research nutritionist
However, the final group - babies of junk-food mothers given the option of an
unhealthy diet - ate the most food, eating nine days worth of food for every
seven days worth consumed by the other babies on the junk food or chow menu.
They ate roughly twice as much as those on the chow-only diets.
The researchers suggested that the "pleasure chemicals" released by the mother
when eating fatty foods might have an effect on the developing brain of the
foetus.
Professor Neil Stickland, who headed the research, said: "The government is
trying to encourage healthier eating habits in school, but this shows that we
need to start during the foetal and suckling life.
"Future mothers should be aware that pregnancy and lactation are not the time
to over-indulge on fatty and sugary treats on the assumption that they are
'eating for two'."
'No lectures'
However, Fiona Ford, a research nutritionist from the University of Sheffield,
said that in the absence of strong evidence that the same effect was present in
humans, it would be wrong to make women feel guilty about eating some unhealthy
snacks during pregnancy.
She said: "A balanced diet is important during pregnancy. While this is
interesting research, these mechanisms are so finely tuned that I don't think
we understand them yet."
Dr Atul Singham, from the Institute of Child Health in London, also said that
he was slightly sceptical about the likely scale of "foetal programming" in
child diet until it could be proven in human studies.
He said: "This is what we are looking into - but at the moment there is no data
in humans to support this, and obviously it is very difficult to carry out
intervention studies such as these in pregnancy."