The researchers examined data on almost 15,500 participants with type 2 diabetes from two major studies, finding that the highest level of consumption of SSBs was associated with a 20% increased risk of all-cause mortality and a 25% raised risk of cardiovascular disease, compared with consumption of the least amounts of these products.
The research, published in BMJ, also showed that drinking coffee, tea, plain water, and low-fat milk reduced the risk of all-cause death and that switching from SSBs to the other beverages was linked to lower mortality.
“Overall, these results provide additional evidence that emphasizes the importance of beverage choices in maintaining overall health among adults with diabetes,” say senior author Le Ma, PhD, department of nutrition, Harvard School of Public Health, Boston, and colleagues.
“Collectively, these findings all point in the same direction. Lower consumption of SSBs and higher consumption of coffee, tea, plain water, or low-fat milk are optimal for better health outcomes in adults with type 2 diabetes,” Nita G. Forouhi, MD, PhD, emphasizes in an accompanying editorial.
Choice of drink matters
Dr. Forouhi, from the University of Cambridge (England), warned, however, that the findings “cannot be considered cause and effect,” despite the large-scale analysis.
Moreover, “questions remain,” such as the impact of beverage consumption on coronary heart disease and stroke risk, and cancer mortality, with the current study providing “inconclusive” data on the latter.
There was also no data on the addition of sugar to tea or coffee, “so the comparative health effects of unsweetened and sweetened hot beverages remain unclear,” Dr. Forouhi points out. Also unknown is whether the type of tea consumed has a differential effect.
Despite these and other reservations, she says that overall, “Choice of beverage clearly matters.”
“The case for avoiding sugar-sweetened beverages is compelling, and it is supported by various fiscal measures in more than 45 countries. It is reasonable to shift the focus to drinks that are most likely to have positive health impacts: coffee, tea, plain water, and low-fat milk,” she notes.
Dr. Forouhi ends by underlining that the current findings tally with those seen in the general population, so “one important message is that having diabetes does not have to be especially restrictive.”
Expanding the evidence
It was estimated that 537 million adults worldwide had type 2 diabetes in 2021, a figure set to increase to 783 million by 2045, say the authors.
Individuals with type 2 diabetes have an increased risk of cardiovascular disease, among many other comorbidities, as well as premature death. Dietary interventions can play an important role in managing these risks.
Recommendations on the healthiest beverages to drink are largely based on evidence from the general population, and data are limited on the best options for adults with type 2 diabetes, who have altered metabolism, the researchers note.
To expand on this, they examined data from the Nurses’ Health Study, which enrolled female registered nurses aged 30-55 years and was initiated in 1976, and the Health Professionals Follow-Up Study, which included male health professionals aged 40-75 years and was initiated in 1996.
For the current analysis, 11,399 women and 4,087 men with type 2 diabetes were included from the two studies, of whom 2,715 were diagnosed before study entry.
Participants’ average daily beverage intake was assessed using a validated food frequency questionnaire administered every 2-4 years. SSBs included caffeinated and caffeine-free colas, other carbonated SSBs, and noncarbonated SSBs, such as fruit punches, lemonades, or other fruit drinks.
During 285,967 person-years of follow-up, there were 7,638 (49.3%) deaths, and 3,447 (22.3%) cases of incident cardiovascular disease were documented during 248,447 person-years of follow-up.
Fully adjusted multivariate analysis comparing the lowest and highest beverage intake indicated that SSBs were associated with a significant increase in all-cause mortality, at a pooled hazard ratio of 1.20, or 1.08 for each additional serving per day (P = .01).
In contrast, the associations between all-cause mortality and consumption of artificially sweetened beverages, fruit juice, and full-fat milk were not significant, whereas coffee (HR, 0.74), tea (HR, 0.79), plain water (HR, 0.77), and low-fat milk (HR, 0.88) were linked to a reduced risk.
The team reported that there were similar associations between beverage intake and cardiovascular disease incidence, at an HR of 1.25 for SSBs, as well as for cardiovascular disease mortality, at an HR of 1.29.
Participants who increased their tea, coffee, and low-fat milk consumption during the course of the study had lower all-cause mortality than those who did not. Switching from SSBs to other beverages was also associated with lower mortality.
The researchers note, however, that there are “several potential limitations” to their study, including that “individual beverage consumption may be correlated with other dietary and lifestyle risk factors for cardiovascular disease incidence and mortality among adults with [type 2] diabetes.”
The study was sponsored by the National Institutes of Health. Dr. Ma has reported no relevant financial relationships. Disclosures for the other authors are listed with the article. Dr. Forouhi has declared receiving support from the U.K. Medical Research Council Epidemiology Unit and U.K. National Institute for Health and Care Research Biomedical Research Centre Cambridge.
A version of this article first appeared on Medscape.com.