Consuming caffeine regularly may correlate to a decreased risk of DR. Photo: Nate Dumlao on Unsplash.

A recent cross-sectional study included 1,350 subjects with type 2 diabetes who underwent DR examination, as reported in the Korean National Health and Nutrition Survey. The researchers graded DR using the modified Airlie House classification system and obtained coffee consumption data through food frequency questionnaires.

The adjusted prevalence of DR was 20%. After adjusting for confounders, the researchers reported a significant decreasing trend of DR prevalence and daily caffeine consumption. This association between coffee consumption and DR was only significant for those under 65, however. The researchers noted that the long effect of diabetes duration in patients aged 65+ may be too strong for something like coffee consumption to impact disease; additionally, they noted it’s likely that those 65+ altered their diet after their diagnosis. Older subjects consumed less alcohol, cigarettes and coffee. However, they pointed out that the cross-sectional study wasn’t powered to assess this finding.

“In Korea, middle-aged and older populations drink more coffee with sugar or creamer than any other age group, but the daily total sugar intake was 61.4g, which is considerably lower than that in the United States (116.4g),” the researchers wrote in their paper. “Although no clear results have been reported with creamers or sugars, it should not be overlooked that excessive intake of saturated fat or simple sugars in cream or sugar can lead to weight gain and insulin resistance.”

Lee J, Park J, Kwon S, et al. Coffee consumption and diabetic retinopathy in adults with diabetes mellitus. Nature Scientific Reports. 2022;12:3547.