In the news: Vitamin D May Help Tackle Pediatric DED; Can Quercetin Help Protect Lens?

Vitamin D & Pediatric Ocular Surface Health

Vitamin D has anti-inflammatory, antioxidant and immunomodulatory properties. Low levels of this hormone-like vitamin correlate with decreased tear production, reduced tear film stability, reduced corneal epithelial healing and greater susceptibility to oxidative stress. Studies also associate poor vitamin D status with dry eye disease (DED).

Marginal or deficient status of vitamin D remains a significant problem in the U.S. pediatric population in 2025. Prevalence rates are high, especially among minority children and adolescents, and the obese. In addition to raising DED risk, low vitamin D can lead to growth and bone health issues, and a higher risk of diabetes and heart disease later in life.

The current prospective study(1) evaluated the ocular surface health of pediatric patients with vitamin D deficiency and assessed the effects of vitamin D treatment on tear function, meibomian gland status and the ocular surface.

Participants included 46 pediatric patients with vitamin D deficiency and 39 sex- and age-matched healthy subjects as controls. The vitamin deficient group received 2000 IU vitamin D/day for 3 months.

DED test parameters assessed included Schirmer test, tear break-up time (TBUT), upper and lower lid meiboscore and meibomian gland loss (MGL), tear meniscus height (TMH), tear meniscus area (TMA), OSDI scores, and corneal fluorescein staining score (CFSS).

Significant improvements were seen in the Schirmer test (p=0.007), TBUT (p=0.03), TMH (p<0.001), TMA (p<0.001), CFSS (p<0.001), and OSDI scores (p=0.016) after vitamin D replacement therapy. Eyelid meiboscore and MGL improved significantly after treatment (p=0.022 and p<0.001, respectively).

No difference was observed in upper meiboscore and MGL after vitamin D therapy, and no difference was seen between the treated and control groups in Schirmer test,TBUT, TMH, TMA, OSDI scores and lower eyelid meiboscore and MGL (p>0.005 for all).

The study authors conclude that restoring vitamin D levels in youth with inadequate levels may improve signs and symptoms of DED. They also point out that the American Academy of Pediatrics recommends 400 IU vitamin D daily for all infants and children, including adolescents.

Protective Role of Quercetin in the Lens?

One of the crucial signaling networks in the eye’s lens is the Hippo pathway – a pathway that regulates the growth and development of lens cells, balancing proliferation and differentiation. The pathway controls the self-renewal of progenitor cells and their differentiation into fiber cells which maintains the transparency and structure of the lens.

An investigative team used a cutting-edge technology (network pharmacology) to pinpoint cataract targets and pathways(2).. Network analysis identified the Hippo pathway as the most relevant cataract pathway and quercetin as the top Hippo-associated compound.

The team then tested whether quercetin reduces cataract pathology by modulating the Hippo pathway in a UVB-induced cataract mouse model. Mice received quercetin with or without a Hippo activator (α-hederin).

Quercetin was found to reduce lens opacification and restore lens histo-architecture (the microscopic tissue structure). It was also shown to reduce measures of oxidative damage (MDA) and to raise levels of the antioxidant enzymes GSH and SOD. Other biomarkers indicated Hippo inactivation and enhanced epithelial survival. In in vitro tests of H202-injured lens epithelial cells, quercetin promoted proliferation and inhibited Hippo signaling which were reversed by α-hederin.

A common flavonoid, quercetin is found in many fruits and vegetables such as onions, apples, tomatoes, kale, and tea. Consuming more could prove lens-protecting.

References

1. Oztürk C, et al. The effects of vitamin D replacement therapy on ocular surface health in children with vitamin D deficiency. Japanese J Ophthalmol. ePub, Oct 28, 2025.
2. Miao S, et al. The protective role of quercetin in cataract lenses and its mechanisms related to the hippo signaling pathway. Inter Ophthalmol. 45:409, 2025.