This study authors warned pregnant women this week against daily intake of sweetened drinks, despite the ruling out a causal link between artificial sweeteners (AS) and preterm birth.
Diseases in infancy and childhood, long-term disabilities and even an early death are all problems associated with preterm births.
Not statistically significant
The International Sweeteners Association (ISA) led the fight back, noting that study associations between preterm birth and low-calorie sweetener use (these include aspartame, saccharin and Ace-K in drinks) was not statistically significant, while subjects' dietary assessments could have been inaccurate.
“The possibility that the results, as in all observational studies, may be influenced by residual and unmeasured cofounding could not be ruled out,” the ISA said.
Although the current study adjusted data to account for some external factors, the ISA cited another study by Dekker et al. (2012) to list other potential factors possibly associated with preterm pregnancy, such as low birth weight and marijuana smoking.
Englund-Ögge et al.’s new study is already available online, and is slated for publication in the September issue of the American Journal of Clinical Nutrition.
It uses data from the ongoing Norwegian Mother and Child Cohort Study (MoBa), which aims to determine the causes of preterm birth by examining lifestyle habits, diet, genetic factors and infections.
Lifestyle and diet
For this study, the researchers, from the Norwegian Institute of Public Health (NIPH), Sahlgrenska University Hospital and Sahlgrenska Academy in Gothenburg examined MoBa data drawn from three questionnaires, each completed by 60,761 pregnant women.
During pregnancy they answered a series of questions relating to lifestyle and diet, including intake of fizzy and non-fizzy drinks using AS and sugar (SS).
“We…found that for those women drinking more than one daily serving of sugar- or artificially sweetened drinks, there was a small increased risk of preterm delivery (before week 37 in pregnancy),” Englund-Ögge et al. wrote.
No strong factors explaining why preterm births occurred had yet been identified, but an association with body mass index and diet as been found, the scientists noted.
“The women who consumed a higher amount of sugar- and artificially sweetened drinks were more likely to have a higher body mass index, a lower education, to be daily smokers or to be single women,” according to the researchers.
Statistical analyses adjusted for the possibility that factors more common among soft drinks consumers – smoking, young age, high BMI – could explain preterm birth, but other similar factors could be involved, the scientists said.
An earlier Danish cohort study by Halldorsson et al. (2010) found an association between artificially sweetened (but not sugar-sweetened soft drinks) and a small increase in preterm births in both normal weight and overweight women.
“Although the Norwegian data confirmed the Danish findings regarding an association between artificially sweetened drinks and preterm delivery, we cannot at present…claim artificial sweeteners have a causal relationship to preterm birth,” the researchers wrote.
Source dismisses ‘data trawling’
Seizing on this admission, one well-placed industry source told BeverageDaily.com that the Norwegian study was “bad science” and dismissed it as “data trawling” that scared people unnecessarily.
“The researchers need to be careful about stating a relationship [between sweetened drinks and preterm birth] on the basis of a study of this nature. A wide range of other external factors could have accounted for these preterm births,” they said.
“Also, if you talk to any obstetrician or midwife, they will tell you that one of the biggest challenges for mums during pregnancy is excess weight and obesity, which can mean higher blood pressure, gestational diabetes.”
The source added: Why point the finger at foods and beverages that are safe – even sugar-sweetened beverages – as part of a balanced diet, since sugar levels in drinks are often the same as in anything else mothers are eating?
“Low-calorie beverages can help people control or maintain weight during pregnancy, which can only be a good thing.”
Title: 'Association between intake of artificially sweetened and sugar-sweetened beverages and preterm delivery: a large prospective cohort study'
Authors: L.Englund-Ögge, A.L Brantsæter, M. Haugen, V. Sengpiel, A.Khatibi, R.Myhre, S. Myking, H.M Meltzer, M. Kacerovsky, R.M. Nilsen, B.Jacobsson.
Source: American Journal of Clinical Nutrition (September 2012), published online ahead of print on August 1.