Vitamin A intake helps prevent diabetes onset in adults

People who have enough vitamin A intake are less likely to develop diabetes, and this benefit is more pronounced among men, reports a study of Chinese adults with plant-based diets.

A total of 17,111 adults (8,577 women) who participated in the China Health and Nutrition Survey between 1989 and 2015 were included in this prospective cohort study. The authors assessed dietary intakes via three consecutive 24-hour dietary recalls combined with a household food inventory.

Diabetes was established through self-reported diagnosis, use of diabetes medication, or additional criterion in 2009 of fasting blood glucose or haemoglobin A1c. Cox proportional hazard models were then used to assess the association of vitamin A intake (total, β-carotene, retinol) with diabetes risk.

Of the participants, 519 men and 531 women developed diabetes during a median follow-up of 11 years. Higher intake of dietary total vitamin A significantly correlated with a reduced risk of diabetes in both men (quintile 5 [Q5] vs Q1: hazard ratio [HR], 0.69, 95 percent confidence interval [CI], 0.49‒0.97; p_trend=0.079) and women (Q5 vs Q1: HR, 0.63, 95 percent CI, 0.45‒0.89; p_trend=0.039).

Furthermore, dietary intakes of β-carotene (Q5 vs Q1: HR, 0.71, 95 percent CI, 0.52‒0.97) and retinol (Q5 vs Q1: HR, 0.58, 95 percent CI, 0.39‒0.85) were inversely associated with the risk of diabetes among men, but not in women.

In dose-response analysis, the association of dietary intakes of total vitamin A, β-carotene, and retinol with diabetes risk in men was L-shaped (p_nonlinearity=0.043), reverse J-shaped (p_nonlinearity=0.001), and linear, respectively.