Dietary linolenic acid intake is positively associated with five-year change in eye lens nuclear density

Dietary fat may affect lens cell membrane composition and function, which are related to age-related cataract. The present study was designed to examine the associations between dietary fat and the change in nuclear lens opacification over five years.

Women aged 52 to 73 years without previously diagnosed cancer, diabetes and cataracts from the Boston, Massachusetts area were selected from the Nurses' Health Study cohort. Four hundred forty women participated in a baseline (1993-95) and a follow-up (1998-2000) eye examination. Intakes of total fat and selected fatty acids were calculated as the average intake from five food frequency questionnaires that were collected between 1980 and baseline. Change in the degree of nuclear density (opacification) was characterized by the difference between baseline and follow-up in pixel density at the central clear zone in the Scheimpflug slit image of the lens.

Intake of alpha-linolenic acid (ALA) was positively associated with change in nuclear density. The geometric mean nuclear density change was 16% greater in the highest quartile category of ALA intake than in the lowest quartile category (P for trend = 0.05). For women in the high tertile category of baseline nuclear lens opacification, the geometric mean change in the highest quartile category of ALA acid intake was 70% higher than the change in the lowest quartile category (P for trend = 0.01). There were no significant associations between other dietary fats and change in nuclear density.

Higher ALA intake was associated with a greater age-related change in lens nuclear density.