A mother's weight before and during pregnancy can have a life-long impact on her children's health, including passing on the extra pounds.
The timing of the birth and the weight of the baby could set the stage for adult obesity and diabetes, Auckland University paediatric endocrinology professor Wayne Cutfield said.
Babies that were premature, small, overdue, first-born and whose mothers had severe morning sickness were more at risk of becoming overweight in adulthood.
"These are scenarios where more than 50 per cent of the population are at risk of obesity and insulin resistance and diabetes."
As soon as a baby deviated from "the average", his or her risk of obesity-related diseases - such as diabetes and heart disease - increased, Prof Cutfield said.
‘The foetal environment, particularly the nutrition environment, is important for health life-long," he said.
Genetics and lifestyle played a role but events early in life were "critically important" to the subsequent health of children.
"The mother's genes that made her big . . . are passed on to the baby.
"However, we now know that obese mothers overeat and a significant portion of those calories are being delivered to the baby. A fat baby is more likely to become a fat child and a fat adult, and on it goes."
A mother's diet could also reprogramme her genes, which were then passed on to her baby.
A third of New Zealand adults are overweight and one in four is obese, according to the latest Health Ministry figures.
Twenty per cent of children aged between 2 and 14 years are considered overweight and one in 12 is obese.
Prof Cutfield will speak at the Australian and New Zealand Obesity Society annual scientific meeting, which begins in Auckland today.
He called for targeted education for women in their reproductive years about the effects of being fat on unborn babies, a better understanding of optimal nutrition in pregnancy, and better awareness of overfeeding small babies past early infancy.
A study of women having IVF treatment highlighted the need for education, as none of them changed their alcohol, tobacco and coffee intake in the leadup to pregnancy.
Sir Peter Gluckman, chief science adviser to the prime minister, has called for all pregnant women to be screened for diabetes to break the obesity cycle.
DOUBTS ON BANS
Banning fizzy drinks from schools and kids' lunchboxes would help shrink the nation but blanket bans barring sugary beverages from being sold in certain cities are not the answer, Otago University medicine and human nutrition professor Jim Mann says.
New York was the first city to ban super-sized sodas at restaurants, movie theatres and stadiums – a move now being challenged in the courts by the soda companies.
"I don't like the concept of completely banning it because we'll never achieve it," he said.
Restricting advertising would be another option.
Professor Mann labelled Coke's latest campaign, inviting people to vote for their name to be printed on labels, as "scandalous".
"On the one hand it's saying: oh, well, we're encouraging people to drink our Coke Zero and other sugar-free beverages and then they push Coca-Cola laden with sugar."
A Coca-Cola spokesman said: "Consumers can choose from our portfolio of low and no-calorie beverages, as well as our regular beverages in smaller portion sizes."
- The Dominion Post
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