Carbohydrate nutrition is associated with changes in the retinal vascular structure and branching pattern in children.

BACKGROUND: Higher intake of carbohydrates and high-glycemic index (high-GI) diets could lead to small vessel dysfunction.
OBJECTIVES: We aimed to assess the associations between intakes of high-GI and high-glycemic load (high-GL) diets, carbohydrate, and the main carbohydrate-containing food groups and retinal microvascular changes in preadolescents.
DESIGN: Students aged 12 y (n = 2353) from a random cluster sample of 21 schools underwent detailed eye examinations. Retinal vessel caliber and fractal dimension were measured from digital retinal images. A validated semiquantitative food-frequency questionnaire was administered.
RESULTS: After multivariable adjustment, children who consumed soft drinks once or more per day had significantly narrower mean retinal arterioles (∼1.9 μm) than did those who never or rarely consumed soft drinks (P-trend = 0.03). When the highest to lowest tertiles of carbohydrate consumption were compared, girls had significantly narrower retinal arterioles (∼1.4 μm; P-trend = 0.03) and boys had wider venules (∼2.3 μm; P-trend = 0.02). In girls only, a higher-GI diet was associated with narrower retinal arterioles (0.98-μm narrowing of retinal arteriolar caliber per SD increase in GI, P = 0.01). Carbohydrate intake and a high-GL diet were associated with greater retinal fractal dimension in girls (highest compared with lowest tertiles: P-trend = 0.003 and 0.01, respectively).
CONCLUSIONS: Greater consumption of carbohydrates and soft drinks was associated with retinal arteriolar narrowing and venular widening. Because these microvascular signs have been shown to be markers of future cardiovascular disease risk, the presence of this risk factor in children could support the need for healthy dietary patterns that include lower consumption of high-GI foods and soft drinks.