Adults who drink at least two sugar-sweetened or artificially sweetened beverages per day may have doubled their risk for developing latent autoimmune diabetes or type 2 diabetes, according to results from a population-based, case-control study in Sweden.
“These findings add support to the accumulating evidence suggesting that high intake of sweetened beverages, both sugar-sweetened and artificially sweetened, is a potential risk factor for type 2 diabetes,” Josefin Edwall Löfvenborg, MSc, a nutritionist and doctoral researcher at the Institute of Environmental Medicine at the Karolinska Institute in Stockholm, and colleagues wrote. “Importantly, these findings indicate that the adverse health effects seen with high sweetened beverage intake also encompass autoimmune forms of diabetes. The excess risk seems not to be fully explained by caloric intake or BMI, opening up for other explanations possibly including direct adverse effects of sweetened beverages on glucose homeostasis and insulin sensitivity.”
Josefin Edwall Löfvenborg
In a retrospective study, Löfvenborg and colleagues analyzed data from 357 adults with latent autoimmune diabetes (LADA; mean age, 59 years; mean diabetes duration, 7.5 months) and 1,136 adults with type 2 diabetes (mean age, 63 years; mean diabetes duration, 5.3 months), all participating in the ESTRID study, a Swedish population-based, case-control analysis initiated in 2010. Researchers also included 1,371 randomly selected controls without diabetes and aged at least 35 years (mean age, 59 years) using the Swedish Population Register. Diabetes classification was based on onset age (aged at least 35 years), glutamic acid decarboxylase autoantibodies and C-peptide levels.
All participants completed questionnaires regarding health and lifestyle factors and a 132-item food frequency questionnaire, in which participants were asked to report habitual food intake during the preceding year. Participants reported the average number of 200-mL servings per day and per week of cola, other soft drinks, diet cola and other diet soft drinks. Fruit juice intake was not evaluated.
Researchers used conditional logistic regression analysis to estimate ORs for LADA and type 2 diabetes in relation to sweetened-beverage intake, including a separate analysis for sugar-sweetened and artificially sweetened beverage intake.
Researchers found that participants who consumed at least two 200-mL servings of sweetened beverages daily (consumed by 6% of participants) had a twofold increased risk for LADA (OR = 1.99; 95% CI, 1.11-3.56) vs. nonconsumers; a 3.5-fold increased risk for LADA was observed among those who consumed five daily servings. Researchers observed no excess risk associated with those who consumed up to two servings per day, but beyond two servings, each incremental daily serving conferred a 15% increased risk for LADA (OR = 1.15; 95% CI, 1.02–1.29). In analyses stratified by sweetened-beverage type, results per daily serving were similar for both sugar-sweetened beverages (OR = 1.18; 95% CI, 1-1.39) and artificially sweetened beverages (OR = 1.12; 95% CI, 0.95-1.32).
Participants who consumed more than two servings of sweetened beverages per day also saw a more than twofold increased risk for type 2 diabetes (OR = 2.39; 95% CI, 1.39-4.09) vs. nonconsumers; risk increased by 20% for each daily serving increment (OR = 1.2; 95% CI, 1.07-1.34).
Among participants with type 2 diabetes, high consumers of sweetened beverages displayed higher homeostasis model assessment for insulin resistance (HOMA-IR) levels (4.5 vs. 3.5; P = .0002) and lower HOMA beta-cell function levels (55 vs. 70; P = .0378) than nonconsumers. Similar tendencies were seen in LADA, according to researchers.
“It was interesting to find that the autoimmune response to the number of soft drinks consumed stayed the same,” Löfvenborg said in a press release. “This could mean that the increased risk of developing LADA in relation to soft drink consumption isn’t directly caused by the immune response killing beta cells — which is what we see in type 1 diabetes.”
Löfvenborg said more studies are needed regarding artificially sweetened beverages before conclusions can be drawn regarding diabetes risk.
“Since this is an observational study, we don’t know what is driving these observed associations; whether it truly is something in the beverage or if it is something in the lifestyle of high consumers that we have not been able to take into account in our analyses,” Löfvenborg told Endocrine Today. “Even though we have tried to adjust for various other dietary and lifestyle factors, there could still be some effect of these that have not been able to catch.” – by Regina Schaffer
For more information:
Josefin Edwall Löfvenborg, MSc, can be reached at the Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE171 77, Stockholm; email: firstname.lastname@example.org
Disclosure: The researchers report no relevant financial disclosures.