A look at lutein, zeaxanthin, astaxanthin, β-cryptoxanthin, capsanthin, and palmitoleic acid.
Eye health supplements are a category of significant interest. According to market research1, the global eye health supplements market stood at $1.9 billion in 2023 and is projected to reach $3.5 billion by 2033, with a CAGR of 6.2% over the forecast period. Specific areas of concern in the category include blue light exposure and dry eye.
Blue Light Exposure
Blue light from digital devices and outdoor light can be harmful to the eyes.2 Nearly one-third of adults spend more than half their waking hours (9+ hr) using a digital device.3 Headache, eye fatigue, and other indications of eye strain are associated with the daily use of video display terminals on computers and other electronic devices and are common with 3 hours/day or more of exposure.4,5 Likewise, more than 70% of American adults report6 their children receive more than two hours of screen time per day, resulting in the following: headaches (8.8%); neck/shoulder pain (5%); eye strain, dry or irritated eyes (9.1%); reduced attention span (15.2%); poor behavior (13.3%); and irritability (13.5%).
Normally, glands above the eyes make tears that keep eyes wet. Dry eye happens when tears don’t do their job. This could mean that glands don’t make enough tears to keep eyes wet, tears dry up too fast, or tears just don’t work well enough to keep eyes wet. Dry eye affects millions of Americans every year, with symptoms including a scratchy feeling (like there’s something in your eye), stinging or burning feelings in your eye, red eyes, sensitivity to light, and blurry vision.7
A Role for Nutraceuticals
The good news is that select nutraceuticals may do much to help protect against these specific areas of concern for the eye. These include lutein, zeaxanthin, astaxanthin, β-cryptoxanthin, capsanthin, and palmitoleic acid.
Lutein and Zeaxanthin
Lutein and zeaxanthin are carotenoid antioxidants8 that protect the eyes and help them filter out harmful blue light from digital devices and outdoor light.9-13 Lutein and zeaxanthin were also shown8 to improve glare performance (e.g., excessive brightness as might be caused by oncoming headlights at night) and to help promote contrast sensitivity (the ability to distinguish an object against its background). Not surprisingly, all of this has resulted in lutein and zeaxanthin making it more comfortable to use computers and other digital devices throughout the day.
Astaxanthin, found in microalgae, is another carotenoid antioxidant with value for a broad range of health and wellness benefits. Research14 has shown that supplementation improved visual accommodation (e.g., the ability of the lens of the eye to change shape, allowing for a change in focus from far to near) and improved eye fatigue.
Research has shown that plasma levels of the carotenoid antioxidant β-cryptoxanthin—found in tangerines, red peppers, and pumpkin—were associated with a lower risk of advanced age-related macular degeneration.15 Being similar in structure to lutein and zeaxanthin, scientists have stated that further research on the role of β-cryptoxanthin on eye health would be useful.16
Capsanthin, found in paprika and red pepper, is a carotenoid antioxidant that helps absorb light. Epidemiological studies indicate a protective role of capsanthin in colon carcinogenesis.17
The omega-7 fatty, palmitoleic acid, is a naturally occurring constituent of animal fats and plant seed oils. Likewise, our bodies produce palmitoleic acid.18 Research has also demonstrated that palmitoleic acid has efficacy in the treatment of dry eye syndrome. This was seen in an open-label study19 where a specific branded palmitoleic acid significantly reduced dry eye by 33%. Another observational study20 found that most patients using the same palmitoleic acid experienced improved eye comfort within 7–14 days and other improvements in eye parameters within 30 days.
The Combination of Lutein, Zeaxanthin, and Astaxanthin
A multicenter, prospective, open-label randomized study21 found that the combination of lutein (10 mg), zeaxanthin (1 mg), astaxanthin (4 mg), and other antioxidants/vitamins were more likely to report clinically meaningful stabilization/improvements in visual acuity, contrast sensitivity, and visual function through 24 months compared with nontreated subjects. A randomized, placebo-controlled, parallel-group clinical trial22 found that the combination of astaxanthin (6 mg), lutein (10 mg), and zeaxanthin (2 mg) resulted in significantly improved eye-hand coordination after video display terminal operation at eight weeks.
The Combination of Capsanthin, Zeaxanthin, and Cryptoxanthin
A 12-week, placebo-controlled, human clinical study23 demonstrated that a combination of capsanthin, zeaxanthin, and cryptoxanthin improved cumulative macular pigment optical density (MPOD)—which reflects the protective capacity of the carotenoids against blue light damage—as well as cumulative photo stress recovery (a measure of visual acuity restoration) and the ability to read under different cases of light exposure, including blue light.
Specific areas of concern in the growing category of eye health supplements include blue light exposure and dry eye. Select nutraceuticals can do much to help protect against these specific areas of concern for the eye.