The frequent consumption of sugary drinks is known to cause overweight and obesity and can contribute to an increased risk of type 2 diabetes. The replacement with calorie-free drinks with artificial sweeteners is no alternative, as these drinks also increase the risk of diabetes.
Sweetened soft drinks account for a large proportion of daily sugar and calorie intake and thus contribute to overweight and obesity. A link between the consumption of such beverages and an increased risk of type 2 diabetes has been shown several times.
The idea of replacing sugary beverages containing artificial sweeteners has become an obvious one and is also recommended by the American Diabetes Society for weight control and thus for diabetes prevention.
However, this does not seem a good idea: the calorie-free variants of sweetened drinks such as cola, soda or iced tea obviously increase the risk of type 2 diabetes - even if only half as much as sugar-containing soft drinks.
Recently it has been suspected that artificially sweetened drinks could also promote the development of type 2 diabetes. So far, however, the study situation here has been weak and in part contradictory.
The American working group of Mengna Huang et al. has therefore now examined the association between the consumption of artificially sweetened and sugary beverages with the incidence of diabetes. They used data from the Women's Health Initiative for this purpose. In this cohort study with postmenopausal women, which was conducted from 1993 to 1998, the consumption of beverages was also recorded using corresponding questionnaires.
The analysis included 64,850 women who were around 60 years of age at the start of their studies. 4,675 developed type 2 diabetes in the observation period of 8.4 years on average. 42,257 women (65%) had stated never to consume artificially sweetened drinks or less than 3x per month, 14,602 (23%) drank such drinks in the range of 1 to 6 units per week, 4,961 (8%) once a day and 3,030 (5%) at least twice a day.
As expected, increased consumption of sugary beverages (≥ 2 a day vs. < 3 a month) was associated with a significantly higher risk of diabetes (hazard ratio: 1.43). However, high consumption of artificially sweetened beverages (≥ 2 a day vs. < 3 a month) was also associated with a 21% higher risk of developing type 2 diabetes.
Both associations were independent of possible influencing factors such as age, ethnicity, family status, and income, educational level, diabetes in the family history, BMI, taking other drugs and comorbidities. The subgroup analysis showed that the negative influence of the consumption of sweetened beverages was most pronounced in obese women (HR 1.26).
On the basis of their data, the authors ran the following estimate: If the women with the highest consumption of sugary drinks permanently replaced one glass of an artificially sweetened soda (355 ml) a day with pure water, they could reduce their long-term diabetes risk by 5%.
Replacing a sugary drink with water a day would reduce the risk by 10%. Replacing sweetened or sugary beverages with pure water thus has great potential to reduce the risk of diabetes. Replacing a sugary drink with a sweetened drink, on the other hand, has no significant change in the risk of diabetes.
As in all pure observational studies, a causality cannot yet be proven and a bias cannot be reliably excluded by other influencing factors. For example, women with an increased risk of diabetes could increasingly use artificially sweetened drinks to maintain their weight, the authors indicated. The advice of going for water when thirst hits, instead of consuming any sugary or artificially sweetened drinks is certainly not the wrong one.
Huang M et al. Artificially sweetened beverages, sugar-sweetened beverages, plain water, and incident diabetes mellitus in postmenopausal women: the prospective Women's Health Initiative observational study; Am J Clin Nutr 2017; 106: 614-22; doi: 10.3945/ajcn.116.145391 https://www.ncbi.nlm.nih.gov/pubmed/28659294