Benefits
Macular Pigment Density
Zeaxanthin is the pigment most concentrated at the center of the macula. A pooled analysis of 20 randomized trials (938 people with AMD and 826 healthy people) found that lutein, zeaxanthin and meso-zeaxanthin supplements raise macular pigment. In a 60-person trial in people with AMD, 8 mg a day of zeaxanthin raised macular pigment about as much as lutein. None of these trials used OPTISHARP Natural.
Zeaxanthin in the AREDS2 eye study
AREDS2 gave 2 mg zeaxanthin with 10 mg lutein a day to people who already had intermediate or one-sided advanced AMD. In the main analysis it did not significantly slow progression to advanced AMD (hazard ratio 0.90, P = 0.12); secondary analyses favored lutein and zeaxanthin over beta-carotene. The zeaxanthin used was DSM's synthetic OPTISHARP, not the later natural version.
Blue Light Filtering
Macular pigment, including zeaxanthin, absorbs short-wavelength blue light before it reaches the light-sensing cells of the retina. This is the proposed reason zeaxanthin is studied for eye health; it is a mechanism, not a demonstrated benefit of OPTISHARP Natural.
Natural Marigold Source
OPTISHARP Natural is extracted from marigold flowers, while DSM's original OPTISHARP was made by chemical synthesis. Both supply free (unesterified) zeaxanthin in the 3R,3'R form found in the eye, and no trial has compared the two for any eye outcome.
Combined with Lutein for Eye Health
Zeaxanthin is usually taken with lutein, as in AREDS2 (10 mg lutein with 2 mg zeaxanthin). In a trial in 108 people with early AMD, 10 mg lutein plus 10 mg zeaxanthin a day raised macular pigment by about 0.058 units over 48 weeks.
Mechanism of action
Macular Pigment Concentration (Foveal)
Zeaxanthin is most concentrated in the fovea, the very center of the macula used for sharp vision, while lutein is spread more widely across the macula.
Blue Light Antioxidant
Like lutein, zeaxanthin absorbs high-energy blue light and can neutralize reactive oxygen species formed in the retina. This comes from laboratory research and is a rationale, not proof of benefit.
3R,3'R-Zeaxanthin Form
Zeaxanthin from marigolds is the 3R,3'R form found in the retina. The synthetic zeaxanthin assessed by the European Food Safety Authority is also at least 96% all-trans 3R,3'R-zeaxanthin, so the natural and synthetic ingredients are chemically very similar.
Photoreceptor Protection
By filtering light and acting as an antioxidant, macular pigment is thought to help protect the light-sensing rod and cone cells. This is a proposed mechanism from laboratory and observational work, not a tested outcome for this product.
Clinical trials
Multicenter, double-masked, placebo-controlled phase 3 trial run from 2006 to 2012, adding 10 mg lutein plus 2 mg zeaxanthin and/or omega-3s to the AREDS formula. The zeaxanthin was DSM's OPTISHARP, sold before the natural version existed. (Age-Related Eye Disease Study 2 Research Group 2013, JAMA)
4,203 people aged 50 to 85 at risk of advanced AMD.
The main analysis was not statistically significant: lutein plus zeaxanthin did not reduce progression to advanced AMD compared with placebo (hazard ratio 0.90, 98.7% CI 0.76 to 1.07, P = 0.12). Exploratory analyses favored lutein and zeaxanthin over beta-carotene, which was linked to more lung cancers in former smokers.
One-year randomized trial comparing 8 mg zeaxanthin, 8 mg zeaxanthin plus 9 mg lutein, or 9 mg lutein a day. (Richer et al. 2011, Optometry)
60 people with mild to moderate AMD (57 men, 3 women; mean age 74.9).
Macular pigment rose in all three groups with no difference between groups. In the zeaxanthin group, high-contrast visual acuity improved by about 1.5 lines, while the lutein-only group did better for low-contrast acuity, contrast sensitivity and glare recovery. Small, almost all-male sample; the brand of zeaxanthin is not stated in the abstract.
48-week randomized, double-masked, placebo-controlled trial of 10 mg lutein, 20 mg lutein, or 10 mg lutein plus 10 mg zeaxanthin a day. (Ma et al. 2012, Ophthalmology)
108 people aged 50 to 79 with early AMD.
Macular pigment rose significantly in the 20 mg lutein group (0.076 units) and the lutein plus zeaxanthin group (0.058 units). Contrast sensitivity differed from placebo only in the 20 mg lutein group, and visual acuity showed a trend toward improvement.
NIH-supported randomized trial of 10 mg lutein plus 2 mg zeaxanthin a day vs placebo softgels, both with prenatal vitamins, from the first trimester; Kemin supplied the softgels. (Addo et al. 2024, Ophthalmol Sci)
47 low-risk pregnant women and their newborns.
Maternal macular pigment rose compared with placebo, and infants' skin and blood carotenoids were higher. Infant macular pigment was 20% higher but not significantly (P = 0.242), an exploratory endpoint. The paper does not name the zeaxanthin brand.