Macular Pigment and Glare Disability

Not Applicable

Completed

Interventions: Dietary Supplement: 12 mg Lutein + Zeaxanthin
Dietary Supplement: Visually identical placebo

Brief Summary: The purpose of this study is:

I. To measure MP optical density (MPOD) in two groups (experimental and placebo) of 50 subjects each (N = 100), during an Lutein + Zeaxanthin supplementation period of 12 months.

II. To test the hypothesis that increases in MP (via 12 mg daily Lutein + Zeaxanthin supplementation) will result in significantly improved visual performance under disability glare conditions.

III. To test the hypothesis that increases in MP (via 12 mg daily L + Z supplementation) will result in significantly reduced photostress recovery times.

IV. To test the hypothesis that increases in MP (via 12 mg daily L + Z supplementation) will result in improved contrast enhancement.

Detailed Description: The following measurements will be taken, before and after supplementation with lutein and zeaxanthin:

Macular pigment optical density (MPOD) Visual performance under glare conditions Photostress recovery times chromatic contrast sensitivity.

Recruitment & Eligibility

Inclusion Criteria

Gender: male or female
Age: 18 - 40 years
BMI: 20-30
No anticipated changes in dieting habits (as relevant to xanthophyll intake).
No anticipated surgical procedures.
Assessed as healthy, based on a pre-study examination including medical history, physical examination, and clinical laboratory. The examination will be performed by an MD or a Nurse Practitioner.
Willingness and ability to give written informed consent and willingness and ability to comply with the study requirements.
Corrected visual acuity (ETDRS): better than 20/60

Exclusion Criteria

BMI <20 or >30
Age <18 or >40 years
Smokers
Current or history of relevant diseases (such as AMD)
Corrected visual acuity worse than 20/60
Inability to reliably perform MPOD measurements by heterochromatic flicker photometry or any of the other ophthalmic tests of the study.
Any condition likely to interfere with normal gastro-intestinal absorption of xanthophylls.
Current use of xanthophyll containing supplements
Use of xanthophyll containing supplements in the past 6 months
Participation in any other study during last 1 month.
Blood donation during the last 3 months.
Known hypersensitivity or allergy to xanthophylls.
Regular intake of medications or supplements, which the principal investigator deems likely to confound the study outcomes.
Suspected lack of compliance with any requirements of the study.
Childbearing potential and unwillingness to refrain from acceptable anticonceptive measures (not including abstinence).
Current pregnancy or breast feeding
Any relevant abnormalities in the routine laboratory tests

Arm && Interventions

Group	Intervention	Description
Intervention	12 mg Lutein + Zeaxanthin	10 mg FloraGlo lutein + 2 mg Optisharp zeaxanthin
Placebo	Visually identical placebo	visually identical placebo

Primary Outcome Measures

Name	Time	Method
Macular Pigment Optical Density	every three months for one year; 12-month measure reported.	optical density of macular pigment layer of the neural retina at 30-minutes of retinal eccentricity

Secondary Outcome Measures

Name	Time	Method
Photostress Recovery Time	improvement in recovery time; baseline recovery time (sec) minus 12-month recovery time (sec)	amount of time needed to recover from exposure to a bright light, and to regain sight of a visual target
Glare Disability	12-month data point only	light energy needed to obscure or veil a visual target; calculated as log-relative energy, which is the physical energy needed for the subject to report that the visual target has been veiled, given the intensity of the target, logged.
Heterochromatic Contrast Sensitivity	12-month data point only	amount of short-wave light energy necessary to obscure of veil a visual target, calculated as log-relative energy, which is the physical energy needed for the subject to report that the visual target has been veiled, given the intensity of the target, logged.