Writing in Nutrition Research, Adrian Lopresti and Stephen Smith from Clinical Research Australia report that supplementation with 10 mg lutein and 2 mg of zeaxanthin per day was also associated with increases in macula pigment optical density (MPOD) – a measure of lutein/zeaxanthin levels in the eye.
“This study demonstrated that supplementation with LZ for 6 months in teenagers aged 13 to 18 years, eating a diet low in fruits and vegetables and using light-emitting diode screens for more than 4 hours daily was associated with significant changes in MPOD (at days 90 and 180) and improvements in cognitive performance (attention and processing speed), but not in non-verbal memory,” wrote Lopresti and Smith.
The study used the Lute-gen ingredient from Bio-gen Extracts Pvt. Ltd, which also funded the trial.
Lutein and brain health
The link between lutein and eye health was first reported in 1994 by Dr Johanna Seddon and her co-workers at Harvard University, who found a link between the intake of carotenoid-rich food, particularly dark green leafy vegetables like spinach, and a significant reduction in age-related macular degeneration (AMD) (JAMA, Vol. 272, pp. 1413-1420).
Numerous studies with data from primates, children, middle-aged people, and the elderly now support the importance of lutein in brain health, which is unsurprising given that the eyes and the brain are connected.
Indeed, recent findings from pediatric brain tissue studies have shown that about 60% of the total carotenoids in the pediatric brain tissue is lutein, and yet NHANES data show that lutein is only about 12% of the carotenoids in the diets, so there is a preference for lutein in the brain (Vishwanathan et al. J Pediatr Gastroenterol Nutr. 2014).
A 2017 study by scientists from Queens University Belfast and the Macular Pigment Research Group at the Waterford Institute of Technology found that higher blood levels of lutein and zeaxanthin may be associated with better cognition, memory, and executive function (Journal of Gerontology, Series A).
Moreover, a 2020 systematic review of randomized clinical trials published in Nutrientsreported that 10 mg per day of lutein for twelve months is consistently associated with improvements in visual episodic memory, verbal episodic memory, inhibition, and attention.
Despite the reports linking lutein to cognition, the new study is said to be the first trial to demonstrate the cognitive benefits of the carotenoid in teenagers.
Study details
Lopresti and Smith recruited 82 teenagers with a high use of screens and a diet low in fruits and vegetables and randomly assigned them to receive either placebo or the lutein-zeaxanthin supplements for six months.
The data indicated that the Lute-gen group displayed significant increases in MPOS in the left and right eyes, while improvements in tests of attention and processing speed were also reported, compared to placebo.
On the other hand, no differences between the groups were recorded for visual reasoning, non-verbal memory (p = 0.935) or performance in a first-person shooter game.
The researchers also found no differences between the groups for self-report measures of attention and sleep.
“Further trials on populations with low MPOD values, experiencing attentional and sleep-related difficulties and utilizing objective and subjective outcome measures will be important to validate and extend the findings from this study,” concluded Lopresti and Smith.
Source: Nutrition Research. doi: 10.1016/j.nutres.2026.06.005. “Supplementation with Lutein and Zeaxanthin increases macular pigment optical density and cognitive performance in healthy teenagers in a randomised, double-blind, placebo-controlled trial”. Authors: A.L. Lopresti & S.J. Smith
