Writing in the journal Nutrients, they reported the results of a study conducted in volunteers who work in computer-based jobs that assessed the effect of either 400 mg of the supplement Oculoxin (from Polish producer Greenvit) or a placebo, taken twice a day for six weeks.
Results showed that the supplement (AKB) improved near vision in 92.3% of participants, and conjunctival hydration (the moisture levels of the membrane that lines the eyelid) improved in 61.5% of patients.
“This is the first study of a preparation based on a combination of natural extracts of aronia, honeysuckle and bilberry,” the researchers wrote.. “And the observations providing a premise for possible activity in the treatment of presbyopia as well as dry eye syndrome.”
Botanical solutions for eye health
Presbyopia, a common condition that causes difficulty focusing on objects at varying distances due to changes in lens elasticity and protein instability over time, affects approximately 1.3 billion people globally.
While standard solutions include the use of contact lenses and glasses or laser eye surgery, natural compounds like iridoids—secondary metabolites present in a variety of plants—and anthocyanins, in particular, have shown potential to improve visual acuity. There is also increasing research into plant-based treatments, including polysaccharides and betaine contained in Goya berries, for dry eye syndrome.
However, as the authors noted, there is a lack of human studies evaluating the effects of standardized extracts containing both polyphenol group compounds (particularly anthocyanins) and iridoids.
Study details
The randomized, double-blind, crossover study recruited 23 participants over the age of 50 and evaluated the effect of supplementation or placebo using the Schirmer test (a test that determines whether the eye produces enough tears to keep it moist), assessment of lid-parallel conjunctival folds (LIPCOF) index and the tear breakup time (TBUT) test, as well as a visual field test.
While the preliminary results showed that the composition of AKB did not change visual acuity in the first six weeks of administration, the next cycle of the study (following a five-week washout period) observed an improvement in near visual acuity in 92.3% of the patients.
Additionally, 80% of patients showed increased conjunctival wetting at the beginning of week six of administration. While this number reduced in the washout period, 61.5% of patients still experienced increased conjunctival wetting by the end of the experiment.
The authors also identified anthocyanins including cyanidin 3-O-galactoside, delphinidin 3-O-arabinoside, cyanidin 3-O-glucoside, cyanidin 3-O-rutinoside, cyanidin 3-O-arabinoside and iridoids including loganin, sweroside, loganic acid in the extract.
As chokeberry extract contains phenolic compounds like anthocyanins and proanthocyanidins, the authors suggested that they may enhance vision by promoting rhodopsin biosynthesis and improving microcirculation.
Research has also shown that honeysuckle berry extract could reduce ocular inflammation by inhibiting the production of pro-inflammatory mediators, and as bilberry extract is rich in anthocyanins, previous research suggests that these compounds are responsible for modulating oxidative stress and protecting retinal cells.
The researchers called for further in-depth studies in suitable populations and exploration of the molecular mechanism of action to prove the activity of the Oculoxin preparation as an effective dietary supplement.
Journal: Nutrients
doi: 10.3390/nu16070926
“Extract from Aronia melanocarpa, Lonicera caerulea, and Vaccinium myrtillus Improves near Visual Acuity in People with Presbyopia.”
Authors: Szumny, D. Et al.