Abstract
Purpose:
Lutein is the predominant carotenoid in human breast milk, and until recently was not included in infant formulas. Lutein and zeaxanthin (LZ) in the retina appears to accumulate rapidly in the first year of life, and early life exposure to LZ in monkeys is related to higher RPE cell density. We examine, for the first time, whether having been exposed to LZ in infancy (via breast milk) is related to the macular pigment optical density (MPOD) in later life among women of the Carotenoids in Age-Related Eye Disease Study (CAREDS), an ancillary study of the Women’s Health Initiative (WHI).
Methods:
CAREDS study visits measured MPOD via customized heterochromatic flicker photometry. 1,794 women aged 53-86 years had complete MPOD data from 5 eccentricities (0.25, 0.5, 1.0, 1.75, and 7.0 degrees from foveal center). Adult dietary intake of LZ was assessed using validated, semi-quantitative food frequency questionnaires, as was anthropometrics and health history. Whether breast or formula fed as an infant was queried six years prior to MPOD measurement, as part of the WHI baseline visits. Mean MPOD at each eccentricity, and MPOD area from 0.25-7.0⁰ was compared in those breast versus formula fed using ordinary least squares linear regression, adjusting for adult intake of LZ.
Results:
MPOD was consistently higher in those breast fed (n=1023) versus formula fed (n=386) at each eccentricity; mean (±standard error) MPOD area was 0.83 (0.02) and 0.76 (0.03), respectively (P=0.03). Adjusting for adult intake of LZ attenuated the association (0.83 vs. 0.77, P=0.05). After adjusting for adult intake of LZ, the difference in MPOD area between breast and formula fed adults was most prominent in those with waist circumference >90 cm (0.75 vs. 0.64, P=0.03).
Conclusions:
Exposure to LZ from infancy (via breast milk or lutein-fortified formulas) may be related to higher MPOD across the entire spatial profile in later life. Additional studies, in younger samples, and which query duration of breastfeeding are warranted.