Artificially sweetened soft drink have become popular because of concerns over the association between sugar sweetened soft drinks and obesity. In response to these concerns, manufacturers have created a range of diet drinks that contain a number of artificial sweeteners, principally aspartame. However, health concerns over aspartame have increased as anecdotal reports and scientific evidence have accumulated to show that high intakes are damaging to the health. In addition, despite their theoretical weight loss appeal, evidence suggests that their consumption is associated with weight gain, diabetes and obesity. In fact, animal studies have confirmed that artificial sweeteners cause increased energy intake, greater body fat accumulation and increased body weight. In addition neurological problems have been reported from consumption of aspartame, possibly because the phenylalanine component is able to lower brain levels of serotonin.
Studies confirm that the nutritional status of the human is particularly sensitive during pregnancy. Both human and animal studies suggest that the nutritional intake during this time can have both short-term and long-term effects on the offspring. Two studies to date1, 2 have suggested that consumption of artificially sweetened drinks is associated with premature birth, which is worrying given the known problems associated with artificial sweeteners. Both studies were published in the American Journal of Clinical Nutrition, with one being performed on Danish mothers and one on Norwegian mothers. For example, in the Norwegian study, the odds ratio for premature birth in those drinking more than one artificially sweetened drink per day was 1.11 compared to those drinking no artificial sweetened drinks. This study also reported an association between drinking sugar sweetened soft drinks and premature birth.
The problem with premature birth is that it increases the chance of prenatal mortality and long-term morbidity. Many studies now confirm that the nutrition supplied to the foetus during development can have long-term health implications for the offspring. In particular, obesity and diabetes is increasingly being shown to be influenced by the nutritional quality of the maternal diet during pregnancy. The association between artificially and sugar sweetened soft drinks and premature birth does not necessarily mean the drinks are the cause of the effect. It could for example be that soft drink consumption is simply a marker for those with a poor diet. The main problem with most low quality diets is that they lack fibre and so the carbohydrate content causes problems with blood sugar control. Soft drinks, with or without artificial sweeteners, may therefore cause blood sugar perturbations that affect the pregnancy outcome.