See Your Eyes In A Healthy Light

It is necessary to keep one’s compass in one’s eyes and not in the hand, for the hands execute, but the eye judges.

Michelangelo

In these studies, the eyes have it when it comes to carotenoids, vitamin D, and more. Our eyes are unprotected when it comes to UV rays and toxin exposure. That’s why it’s so important to protect them on the outside and from the inside out. Read on to discover how nutrients can truly make a difference for your healthy eyes.

Lutein and zeaxanthin improved visual memory

In this study, 90 volunteers, aged 40 to 70, who reported problems with memory or attention, took a placebo or 10 mg of lutein plus 2 mg of zeaxanthin per day.

After six months, doctors used standard tests to measure changes in episodic memory—those of everyday events such as times, places, and associated emotions—and in immediate and delayed word recall, location recall, learning recall, and word and picture recognition, all of which improved significantly in the lutein and zeaxanthin group compared to placebo.

Because of the relationship between visual memory and cognitive decline, doctors said lutein and zeaxanthin may help prevent this age-related condition.

Reference: Frontiers in Nutrition; 2021, Vol. xx, No. x, 644-7

Bilberry reduces video-screen eye fatigue

Healthy pupil constriction and dilation

Reading on a video screen is more taxing than reading printed text due to screen glare, poor lighting or posture, or viewing at the wrong distance or angle, among other reasons. People on computers tend to blink less than while reading print, drying the eyes and contributing to strain.

In this study, 32 healthy adults with video screen eye fatigue took a placebo or 120 mg of anthocyanin-rich bilberry extract powder per day. After six weeks, compared to placebo, those taking bilberry had smoother constriction and dilation of the pupils, clearer vision, less watery eyes, and less eye fatigue.

Discussing the findings, doctors said one of the symptoms of video-screen eye strain is a decrease in pupil constriction and dilation. “Pupillary constriction increases the depth of focus and contributes to the expansion of the clear vision region,” doctors said, meaning smooth constriction increases the range of distance people can clearly see.

Reference: Functional Foods in Health and Disease; 2021; Vol. 11, No. 3, 116-46

Vitamin D for Eyes

People with internal inflammation of the eye, a noninfectious condition called uveitis, were more likely to have low levels of vitamin D. In this review of 16 studies covering people with several forms of uveitis, doctors found consistent evidence of a link to low levels of vitamin D.

People with autoimmune diseases are also more likely to develop uveitis and to be low in vitamin D, which doctors confirmed in the findings as well.

Doctors said there is a large body of evidence showing vitamin D regulates inflammatory processes, and studying vitamin D in uveitis may advance scientific understanding of treating and preventing disease.

Reference: Survey of Ophthalmology; 2022, Vol. 67, No. 2, Published Online

Vitamin D reduces chances for AMD

Age-related macular degeneration (AMD) usually develops after age 50 and is the main cause of blindness later in life in developed countries. In this study, doctors compared vitamin D levels in 93 men and women with AMD to vitamin D levels in 93 AMD-free participants. Participants with AMD had early, intermediate, or advanced forms of the condition.

Overall, those with any form of AMD had average circulating vitamin D levels of 15 nanograms per milliliter of blood (ng/mL) compared to AMD-free participants, whose average levels were 21 ng/mL. Doctors said even though the study was relatively small, the results suggest a direct association between higher vitamin D levels and lower chances for developing AMD.

Reference: BMC – International Journal of Retina and Vitreous; 2022, S40942

Carotenoids in lactating moms

Carotenoids are important for visual and cognitive development in newborns. Measuring carotenoid levels in the macula of the eye is one way to gauge carotenoids in the diet. In this study, doctors measured carotenoid pigment levels in the macula of 80 mothers during the first three months postpartum, and obtained breastmilk samples to measure dietary nutrients.

Mothers with higher breastmilk levels of alpha-carotene, and two types of lutein, also had higher carotenoid levels in the macula, a measurement doctors refer to as macular pigment optical density (MPOD).

Doctors explained that alpha-carotene is not a macular pigment, but because it was linked to higher MPOD levels in this study, alpha-carotene may also signal healthy carotenoid levels in the diet.

Reference: Nutrients; 2022, Vol. 14, No. 1, nu14010182

Flavonoids improve outcomes in AMD

Quercetin and the catechins

One type of age-related macular degeneration (AMD) produces new, leaky blood vessels under the macula and retina of the eye, quickly distorting or destroying vision in the center of the field of vision. In this study, 494 participants with this “wet” form of AMD got standard anti-blood-vessel-growth therapy for 12 months. Doctors validated flavonoids in the diet using a food-frequency questionnaire.

Those who got the least of three types of flavonoids in the diet; quercetin, epigallocatechin, and epigallocatechin-gallate, had significantly worse vision than those who got the most of these flavonoids. The low-flavonoid group was also twice as likely to have leaky blood vessels and fluid beneath the macula and retina.

Discussing the findings, doctors said in addition to having general antioxidant and anti-inflammatory effects, quercetin and the catechins may inhibit abnormal blood-vessel-forming activity in the eye, may slow the progression of wet AMD, and help preserve the central field of vision.

Reference: European Journal of Nutrition; 2021, s00394-021-02582-4

BetsyHealth Note: This article is for educational purposes only. It is not intended to diagnose, treat, prevent or cure any disease. Consult your healthcare provider before trying a supplement, especially if you have a medical condition, including being pregnant or nursing, take prescription or over-the-counter medications, or are planning on having surgery.

Article copyright 2022 by Natural Insights for WellBeing. All rights reserved. Used with permission.

Photo by Jan Krnc: