Manitoba, Canada  – Women who drink diet fizzy drinks during pregnancy are more likely to have overweight children, researchers have found.
A study of 3,000 mothers found what researchers called a ‘paradoxical’ link between drinking artificial sweeteners, which carry fewer calories than sugar, and having an overweight baby, Mail Online health news reported.
The scientists found that mothers who during pregnancy drank artificially sweetened drinks every day were twice as likely to have a baby who was overweight when they were 12 months old.
The research team, from the University of Manitoba in Canada, suggested children exposed to artificial sweeteners in the womb might develop a sweet tooth.
This, in turn, means they consume too much calorie-heavy food when they are born. The scientists said they had no proof for this theory, as their research merely looked at trends between diet in pregnancy and their child’s weight, rather than the biological links between the two.
But they pointed to previous research on rats, which found that babies whose mothers had been fed artificial sweeteners demonstrated a preference for sweet foods and went on to put on weight.
Writing in the medical journal JAMA Paediatrics, the scientists said: ‘To our knowledge, our results provide the first human evidence to support these findings, suggesting that prenatal nonnutritive sweeteners exposure may contribute to infant weight gain and early childhood obesity.’
The team found that 30 percent of mothers reported drinking artificially sweetened drinks – including diet fizzy drinks and sweetened tea and coffee.
Some 5 percent drank these drinks every day, and these women’s children were twice as likely to be overweight at the age of 12 months, compared to those whose mothers never drank diet drinks.
The same trends were not seen among women who drank normal fizzy drinks or hot drinks sweetened with sugar.
The team wrote: ‘Given the current epidemic of childhood obesity and the widespread consumption of artificial sweeteners, further research is warranted to replicate our findings … and study the underlying biological mechanisms.’
Other scientists, however, questioned the findings suggesting women who drank diet drinks everyday were more likely to be overweight in the first place, and therefore may have simply passed this problem to their children.
Professor Kevin McConway, an expert in applied statistics at The Open University, said: ‘Perhaps the increased risk of being overweight was indeed caused by the artificially sweetened drinks or perhaps it was caused by something else that was unusual about the 5 percent of mothers.
‘The researchers made statistical corrections to allow for differences in things they knew about, that may have made this group unusual apart from their sweetened drink consumption, such as maternal smoking and diabetes, a measure of the overall quality of their diet, the duration of breastfeeding, and several more.
‘But they can’t know for sure they accounted for all these things completely, and there may be other aspects of these women’s unusualness that could not be taken into account at all because they weren’t recorded.’
From his side, Dr Janine Elson, spokesperson for the Royal College of Obstetricians and Gynaecologists, added: ‘Maternal and childhood obesity are growing problems in the UK with a quarter of women and nearly a third of children aged two to 15 classed as being very overweight or obese.
‘While the study found children of mothers who reported drinking artificially sweetened drinks during pregnancy had an increased risk of being overweight, further research is needed to confirm whether the results seen in this study can be replicated.
‘Pregnant women are already advised to cut down on foods high in fat and sugar – including fizzy drinks – as these can contribute to weight gain.
‘Water is the healthiest way to keep hydrated.’
Gavin Partington, director general of the British Soft Drinks Association said: ‘Even the authors acknowledge this is a limited study which did not consider overall diet and lifestyle.
‘Decades of clinical research show low-calorie sweeteners, such as those in diet drinks, have been found to help consumers manage their calorie intake when part of an overall healthy diet.’