In a double-blind, randomized, placebo-controlled study of 34 Singapore older adults, consuming grapes — a natural source of antioxidants and other polyphenols — for 16 weeks improved key markers of eye health.
Regular intake of grapes may improve eye health in older adults, specifically in augmenting MPOD, which can be explained by an increase in plasma total antioxidant capacity and phenolic content, and the downregulation of AGEs. Image credit: Couleur
Oxidative stress is a key risk factor for visual impairment and consuming dietary antioxidant-rich foods may help in managing visual impairments.
However, a limited number of studies have investigated the effect of dietary antioxidant-rich food including grapes on eye health in older adults.
“Key risk factors for eye disease include: (i) oxidative stress and (ii) high levels of ocular advanced glycation end products (AGEs),” said Dr. Jung Eun Kim, a researcher at the National University of Singapore, and colleagues.
“AGEs may contribute to many eye diseases by damaging the vascular components of the retina, impairing cellular function, and causing oxidative stress.”
“Dietary antioxidants can decrease oxidative stress and inhibit the formation of AGEs, with possible beneficial effects on the retina, such as an improvement in macular pigment optical density (MPOD).”
In a double-blind, randomized, placebo-controlled trial, the authors looked at the impact of regular consumption of grapes on macular pigment accumulation and other biomarkers of eye health.
The study involved 34 human subjects who consumed either grapes (equivalent to 1.5 cups of grapes per day) or a placebo for 16 weeks.
The grape eaters showed a significant increase in MPOD, plasma antioxidant capacity, and total phenolic content compared to those on placebo.
Those who didn’t consume grapes saw a significant increase in harmful AGEs, as measured in the skin.
“Our study is the first to show that grape consumption beneficially impacts eye health in humans which is very exciting, especially with a growing aging population,” Dr. Kim said.
“Grapes are an easy, accessible fruit that studies have shown can have a beneficial impact in normal amounts of just 1.5 cups per day.”
The findings appear in the journal Food & Function.
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Weili Hu et al. 2023. Impacts of regular consumption of grapes on macular pigment accumulation in Singapore older adults: a randomized controlled trial. Food Funct 14: 8321-8330; doi: 10.1039/D3FO02105J
