Published research noted that lutein is found in the brain, suggesting that this antioxidant may have beneficial effects on cognition.
STORY AT-A-GLANCE
- Of all the known carotenoids, only lutein and zeaxanthin cross the blood-retina barrier to form macular pigment.
- Lutein is also found in the brain, hinting at its importance for cognitive function.
- Lutein, found in green leafy vegetables, egg yolks, and more, helps form the retinal macular pigment, which is responsible for optimizing your visual performance and serves as a biomarker for the risk of macular diseases.
- Lutein is protective against age-related macular degeneration, cataracts, glaucoma, and other eye diseases.
- Among young and older adults, lutein and zeaxanthin supplementation improves cognitive function.
Lutein for Vision Health
Lutein concentrates in your macula[5]—the part of your retina responsible for central vision. Along with zeaxanthin and mesa-zeaxanthin (a metabolite of lutein), these three carotenoids form the retinal macular pigment, which not only is responsible for optimizing your visual performance but also serves as a biomarker for the risk of macular diseases.[6]Lutein is also found in the lens, where it helps protect against cataracts and other age-related eye diseases.[7] Among carotenoids, lutein is the most efficient at filtering out blue light—the type that comes from cellphones, computers, tablets, and LED lights.
“As the peak wavelength of lutein’s absorption is around 460 nm which lies within the range of blue light, lutein can effectively reduce light-induced damage by absorbing 40 percent to 90 percent of incident blue light depending on its concentration.
“As inflammation and abnormal angiogenesis in retinal vasculature are major pathogenic mechanisms of many ocular diseases, lutein’s functions in suppressing inflammatory response and VEGF expression make it effective in reducing the severity of these diseases,” the team noted.[11] Further, lutein may improve visual acuity while helping to reduce cell loss after injury.[12]
Lutein for AMD, Cataracts, and Other Eye Diseases
In my view, the most important strategy to prevent age-related macular degeneration (AMD) is through the radical lowering of the omega-6 fat linoleic acid. AMD was virtually unknown prior to the refining of seed oils in the late 1800s. Now it is a leading cause of blindness.Lutein also may help prevent AMD,[13] which is the leading cause of vision loss and blindness for Americans aged 65 and older.[14] By 2050, it’s estimated that 288 million people worldwide will be affected—up from 196 million in 2020.[15]
Not only are higher blood levels of lutein and other carotenoids associated with a lower risk of AMD, but one study found people with the highest lutein and zeaxanthin intake had a 65 percent lower incidence of neovascular AMD compared to those who consumed the least.[16]
Lutein also shows promise for diabetic retinopathy, which affects one-third of diabetes patients. [17] Along with improving retinal thickness and function, lutein may lower the risk of development or progression of diabetic retinopathy.[18] Cataracts, which are estimated to affect over 90 percent of adults aged 70 and over, are also less common in people with higher lutein intakes.
In one study, those who consumed the most lutein had a 50 percent lower likelihood of cataracts than those who consumed the least.[19] Glaucoma, another leading cause of blindness worldwide, is also linked to lutein consumption. A systematic review revealed that lutein enhanced neuroprotection of retinal ganglion cells, helping to preserve synaptic activity.[20]
Further, not only was greater consumption of carotenoids in the diet associated with a lower glaucoma risk, but higher carotenoid levels in macular pigment helped improve visual performance in eyes affected by the disease.[21] Even myopia, or nearsightedness, which causes faraway objects to appear blurry while close-up objects look clear, may have a lutein connection.
Lutein Optimizes Brain Health Too
While lutein is well-known for its role in eye health, its role in brain health is being increasingly explored. The connection makes sense, since as your vision worsens with age, so too may your cognitive abilities.Research shows visual impairment at a distance is associated with declining cognitive function over time, while “maintaining good vision may be an important interventional strategy for mitigating age-related cognitive declines.”[23]
Meanwhile, studies support the beneficial effects of lutein on brain health. In a trial of young, healthy adults, supplementation with lutein and zeaxanthin improved levels of these carotenoids in the central nervous system along with boosting cognitive function.[24]
Among older adults with a mean age of 73.7 years, lutein and zeaxanthin supplementation also improved cognitive function, including boosts in complex attention and cognitive flexibility domains, compared to those taking a placebo.[25]
Men taking part in the study also had improvements in composite memory. These benefits were seen with a daily lutein and zeaxanthin dose equivalent to that found in one-half cup of cooked kale or 1 cup of cooked spinach.[26]
A literature search involving eight clinical trials further revealed that lutein and zeaxanthin in the blood or macula are associated with cognitive performance, and “there is an inverse relationship between a higher amount of macular pigment in the blood and lower risk of mild cognitive impairments or Alzheimer’s disease.”[27]
“While some age-related cognitive decline is to be expected in healthy aging, our data suggest that these effects may be less pronounced among adults with greater retinal carotenoid status, a marker of dietary patterns characterized by greater intake of green and leafy vegetables. Furthermore, these practices may provide neuro-cognitive benefit before the onset of older age, in early to middle adulthood.”
Lutein Is Also Good for Cardiometabolic Health
Lutein’s ability to protect against oxidative stress may also boost cardiometabolic health, according to a systematic review and meta-analysis. Both higher dietary intake and higher blood concentrations of the carotenoid were associated with better cardiometabolic health, including a lower risk of metabolic syndrome, coronary heart disease, and stroke.[30]Top 10 Sources of Lutein
Your body cannot make lutein, so you must get it from your diet. Following are 10 foods that are particularly rich sources of lutein.- Dark leafy greens
- Carrots
- Broccoli
- Egg yolks
- Red and yellow peppers
- Sweet corn
- Avocados
- Raspberries
- Cherries
- Paprika
Further, consuming eggs along with vegetables that contain lutein may increase its absorption. In fact, eating whole eggs along with a raw mixed-vegetable salad increased absorption of lutein and zeaxanthin by four- to five-fold.[32][33]
“Our stratified analyses suggest the importance of providing lutein at sufficiently high doses and durations: daily doses of at least 20mg showed efficacy within 6 months, compared to 1 year for daily doses of 10mg. However, at least one study showed that 10 mg lutein had the same effect as 20 mg per day, which contradicts our results.
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