NCT06237127

Effects of Goji vs. Fiber on Macular Degeneration

Effects of Goji Berry Intake on Risk of Age-related Macular Degeneration: A Randomized Clinical Trial

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 60 (estimated)
• Sponsor: University of California, Davis · Academic / Other
• Sex: All
• Age: 65 Years – 95 Years
• Healthy volunteers: Accepted

Summary

The goal of this project is to conduct a clinical trial in 60 participants ranging from age 65-95 who are at risk for age-related macular degeneration (AMD). The study will evaluate the effects of 14g of goji berry intake or an equivalent amount and type of fiber, five days a week for six months, on visual health, gut microbiome profiles, skin carotenoid measures, and lipoprotein profiles.

Detailed description

Age-related macular degeneration (AMD) is the third leading cause of blindness worldwide. The disease occurs when the macula in the central retina develops lesions due, in part, to the loss of the protection of macular pigments zeaxanthin, lutein, and meso-zeaxanthin, which are responsible for light filtering and oxidative defense. The major risk factor for AMD is aging, and currently, no definitive prevention for AMD exists. Goji berry (Lycium Barbarum) is a fruit that has been used as traditional medicine in Asian countries for more than 2,000 years. Modern science has identified potential benefits of the berry in oxidant defense, immune regulation, diabetes, and vision in animal and cell models. Nonetheless, evidence regarding the effects of goji berries on human health is scarce. The bioactive components of goji berries include zeaxanthin, lutein, Lycium Barbarum polysaccharides-protein complex, betaine, cerebroside, minerals, and vitamins. Importantly, goji berries contain the highest concentration of zeaxanthin among all commonly consumed foods. Previous clinical studies have shown that goji berries have a high bioavailability of zeaxanthin, and that macular pigment optical density (MPOD) was increased after supplementation. This study uses macular pigment optical volume (MPOV; a measure that integrates MPOD across multiple macular eccentricities) as the primary outcome measure. It is unknown if the changes in MPOV will be associated with other functional changes or anatomic conditions in the eye among a population with small drusen, a risk factor for AMD. In addition, the impact of goji berry intake on the gut microbiome profile and associated metabolites is unknown, and potentially important in understanding the mechanism(s) of action. Participants who meet the eligibility criteria will be enrolled and will be randomized 1:1 to the goji berry arm or fiber arm of the study. Over the course of approximately 180 days, participants will consume the assigned food item five days per week and attend three study visits. Study visits will include ophthalmic imaging and testing, skin carotenoid measurements, completion of a food record, height, weight, handgrip strength, blood pressure measurement, and fasting blood collection. At 2 timepoints participants will be asked to provide a stool sample (collected within 24 hours of visit).

Conditions

• Age-Related Macular Degeneration

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Goji berry	Participants will be instructed to consume 14 grams of goji berries 5 days a week for 6 months
DIETARY_SUPPLEMENT	Fiber	Participants will be instructed to consume the fiber supplements 5 days a week for 6 months

Timeline

• Start date: 2024-04-29
• Primary completion: 2026-06-30
• Completion: 2027-06-30
• First posted: 2024-02-01
• Last updated: 2025-06-24

Locations

1 site across 1 country: United States