Association between myopia and refined carbohydrate consumption: A cross-sectional study from the Constances cohort

The effects of refined carbohydrate consumption on the prevalence of myopia have been little studied. The aim of this study is to explore the potential link between this consumption and myopia in individuals aged 40 or under in the population-based Constances cohort, in conjunction with other known risk and confounding factors.

The association between the probability of myopia in at least one eye and refined carbohydrate consumption was tested for 5271 participants, aged 40 or younger, in conjunction with education level, physical activity, energy intake, age, sex, fasting blood glucose, Body Mass Index (BMI), and Mediterranean diet quality. Refined carbohydrate intake was estimated by glycemic load. Myopia was assessed by the Monoyer score. Significant sex interactions led to stratified analysis by sex.

The risk of myopia was significantly increased for men with refined carbohydrate consumption (p = 0.012, Odd Ratio (OR) = 1.12, Confidence Interval (CI) = 1.02-1.22) but not for women (p = 0.657, OR = 1.02, CI = 0.94-1.10). Some previously identified myopia risk factors were concurrently observed: a higher level of education increased the probability of myopia in both sexes (men p < 10^-11, OR = 1.36, CI = 1.24-1.49; women p = < 10^-4, OR = 1.19, CI = 1.09-1.28), while a higher level of physical activity might be protective in men (p = 0.08, OR = 0.93, CI = 0.85-1.01).

This research reveals how high refined carbohydrate consumption might influence myopia and confirms recent studies on its risk factors. It also highlights significant sex differences in the prevalence and factors associated with myopia, emphasizing that modifiable risk factors, crucial for public health initiatives, may vary between men and women.