Zeaxanthin is a type of carotenoid found in your eye cells.
It’s a powerful antioxidant, known for its numerous health advantages. These include lowering the likelihood of diseases related to aging eyes, such as macular degeneration, glaucoma, and cataracts.
This article delves into zeaxanthin, discussing what it is, its health benefits, and possible risks. It also highlights major food sources and provides insights into zeaxanthin supplements.
In this article
What is zeaxanthin?
Zeaxanthin, a member of the carotenoid family, is naturally present in the human eye. Alongside zeaxanthin, your eyes also contain lutein and meso-zeaxanthin.
It’s believed that meso-zeaxanthin is produced when your body processes other carotenoids, and it’s not usually obtained directly from your diet.
Carotenoids are colorful, fat-soluble, antioxidant compounds, found in certain algae, bacteria, fungi, plants, fruits, and vegetables.
These are vital nutrients that must be sourced from your diet.
Out of 700 known carotenoids, only around 20 are consistently detected in the human body, with zeaxanthin and lutein predominantly located in the human eye.
Zeaxanthin and lutein are present in various fruits, vegetables, and animal-based foods like egg yolks.
They are part of the xanthophyll class of carotenoid pigments, abundantly found in structures exposed to light in both plants and the human eye.
In research, zeaxanthin and lutein are often studied together due to their similar roles in the eye and the body’s ability to convert lutein into zeaxanthin.
Zeaxanthin is concentrated in the central part of the retina, while lutein is more in the outer areas of the retina. They together constitute the macular pigment of the eye.
Both provide antioxidant benefits, with zeaxanthin being particularly potent.
For humans, carotenoids like zeaxanthin are most recognized for their function in maintaining eye health and vision, and in reducing the risk of eye-related conditions.
Summary: Zeaxanthin, a vital antioxidant in the xanthophyll carotenoid family, is one of the two specific carotenoids located in the human eye. It’s crucial for maintaining eye health, supporting clear vision, and helping to minimize the chances of developing eye diseases.
Zeaxanthin’s antioxidant and anti-inflammatory effects in the eye
Antioxidants serve as the body’s defense against oxidative stress, which is triggered by unstable molecules known as free radicals or oxidants. They help reduce the levels of these harmful molecules and lessen inflammation in the body.
An excess of free radicals and ongoing inflammation can lead to various health issues, including:
- age-related macular degeneration (AMD)
- dementia
- cancer
Moreover, exposure to blue light has been found to escalate the production of free radicals and oxidative stress in the eyes, posing a potential risk to eye health.
Studies indicate that zeaxanthin can mitigate oxidative stress and damage in the eye by absorbing blue light. This absorption reduces inflammation and the likelihood of eye diseases.
Remarkably, the eye layers most exposed to light contain approximately 75% zeaxanthin, which can absorb up to 90% of blue light, thereby shielding the retina from damage induced by light.
Summary: Zeaxanthin acts as a shield for your eyes, absorbing detrimental blue light that could otherwise cause harm. Its antioxidant and anti-inflammatory properties help diminish the risk of eye diseases.
Lower risk of eye diseases
Extensive research highlights the crucial role of zeaxanthin in maintaining eye health over a person’s lifetime. It’s particularly linked to a reduced risk of age-related eye diseases, including AMD, cataracts, and glaucoma.
These conditions result in the deterioration of the macula in the eye, which is essential for detailed vision. This is also the region where the carotenoids zeaxanthin and lutein are stored.
Conditions such as cataracts, glaucoma, and diabetic retinopathy involve damage to the eye’s nerves, often caused by prolonged high blood sugar levels, a common issue in diabetes.
Suggested read: 8 impressive health benefits of carrot juice
In the United States, AMD is the primary cause of blindness in individuals over 40.
Zeaxanthin’s antioxidant properties aid in preventing oxidative stress, reducing eye inflammation, and safeguarding the macula from harm.
Zeaxanthin is also crucial for eye development in fetuses and optimal vision in young adulthood.
A diet rich in zeaxanthin and other antioxidants can increase the macular pigment’s density and is linked to a lower risk of eye diseases.
Summary: Zeaxanthin is vital for maintaining eye health throughout a person’s life and is linked to a lower incidence of age-related eye diseases such as age-related macular degeneration, cataracts, glaucoma, and diabetic retinopathy.
Zeaxanthin’s potential benefits for brain health and cognitive function
Zeaxanthin is not only important for vision but is also found in brain regions linked to cognition, movement coordination, and decision-making.
While there has been less research on zeaxanthin’s benefits for the brain compared to the eyes, studies suggest that higher levels of zeaxanthin in individuals with Alzheimer’s correlate with a reduced mortality rate from the disease.
Other research indicates that taking 2 mg of zeaxanthin daily may not enhance cognitive function in people with Alzheimer’s.
The relationship between dietary zeaxanthin intake and its effects remains uncertain. It’s estimated that the average daily intake of zeaxanthin in the U.S. is 1.3 mg, though it can be as high as 25 mg in certain South Pacific populations.
Further research is needed to better understand the connection between zeaxanthin, cognitive function, and Alzheimer’s disease.
Summary: Zeaxanthin is present in brain areas associated with decision-making, movement control, and cognition. It might be linked to improved symptoms of Alzheimer’s disease. Although the findings are promising, further research is necessary.
Zeaxanthin’s role in UV protection and skin health
Zeaxanthin is also present in significant quantities in human skin.
Suggested read: 11 incredible benefits and uses of black rice
Similar to its function in the eyes, zeaxanthin in the skin absorbs damaging blue light waves and combats oxidative stress from free radicals.
Various factors, including nutritional deficiencies and ultraviolet (UV) radiation from the sun, contribute to skin aging and sensitivities.
Common signs of skin aging include:
- dryness or roughness
- formation of wrinkles
- loss of skin elasticity
- skin discoloration
Studies suggest that zeaxanthin’s UV protective properties can help alleviate signs of skin aging. Benefits were observed both from diets rich in zeaxanthin and from the use of skin creams containing zeaxanthin alongside other antioxidants.
Summary: Zeaxanthin, found in human skin, offers UV protection which can help reduce signs of skin aging such as dryness, wrinkles, discoloration, and loss of elasticity.
Other potential health benefits of zeaxanthin
Zeaxanthin may also present various other health benefits, including:
- May safeguard kidney health. A lower level of xanthophyll carotenoids, including zeaxanthin, is linked to a higher risk of kidney disease. Consuming zeaxanthin through egg yolks may also provide antioxidant advantages for individuals with chronic kidney disease.
- Potential liver disease treatment. Zeaxanthin dipalmitate, extracted from goji berries, shows promise in protecting the liver by minimizing inflammation and helping to prevent liver scarring, a precursor to liver disease. It’s being investigated as a potential therapeutic agent.
- Enhanced cellular communication. Zeaxanthin and other carotenoids might contribute to cell-to-cell communication and the maintenance of homeostasis in the body – the necessary physical and chemical balance for optimal health. This area requires more research.
While the primary focus of zeaxanthin research has been on vision and eye health, its effects on other body parts are less explored and warrant further investigation.
Summary: Zeaxanthin may offer protection for kidney health, help maintain bodily homeostasis, and potentially serve as a therapeutic agent for liver disease. More comprehensive research is needed to explore these diverse roles of zeaxanthin.
Zeaxanthin food sources
Zeaxanthin is naturally present in various fruits and vegetables, with dark leafy greens being particularly abundant in it.
Suggested read: The 14 healthiest vegetables on earth
In scientific literature, foods containing zeaxanthin and lutein are often grouped together. This is likely because lutein can transform into meso-zeaxanthin in the eye, and also due to the generally low levels of zeaxanthin in the average diet.
Goji berries are noted for having a high concentration of zeaxanthin. Both the fruit and seeds are substantial sources.
Corn, egg yolks, and human breast milk are other highly bioavailable sources, meaning the zeaxanthin they provide is readily absorbed by the body.
Below is a list of other foods rich in both zeaxanthin and lutein, showcasing the amount found per 100 grams:
- spinach, raw: 12.2 mg
- pistachios, raw: 2.9 mg
- green peas, raw: 2.5 mg
- romaine lettuce, raw: 2.3 mg
- summer squash, boiled: 2.3 mg
- Brussels sprouts, boiled: 1.2 mg
- broccoli, raw: 1.4 mg
- pumpkin, boiled: 1.0 mg
- asparagus, boiled: 0.8 mg
- carrots, raw: 0.3 mg
While there’s no officially recommended daily intake for zeaxanthin, consuming at least 2 mg daily may yield health benefits.
Studies indicate that the lowest risks of AMD and reduced cataract progression were associated with daily intake of 5–6 mg of zeaxanthin.
It’s possible to consume 5–10 mg of combined zeaxanthin and lutein through a varied diet, including foods like orange bell peppers, corn, and eggs.
Summary: Key sources of zeaxanthin include goji berries, corn, eggs, and human milk, as well as leafy vegetables like spinach and kale. While no daily intake recommendation exists, consuming certain amounts has been linked to eye health benefits.
Zeaxanthin supplements
The use of zeaxanthin supplements, particularly those aimed at eye health, is on the rise.
Research indicates that zeaxanthin supplementation can enhance the density of the macular pigment in the eye.
In one study, participants took zeaxanthin supplements for a period ranging from 6 to 24 months. Results showed that 36–95% of participants experienced an increase in macular pigment density. However, the degree of response varied significantly among individuals.
A higher density of macular pigment is correlated with a reduced risk of AMD.
Summary: Research suggests that zeaxanthin supplements can increase the macular pigment density in the eye, potentially reducing the risk of AMD. Further studies are needed to establish safe and effective dosages.
Potential risks of zeaxanthin
Currently, zeaxanthin is considered relatively safe, though scientific conclusions aren’t definitive.
Concerns have been raised about consuming xanthophylls (which include zeaxanthin) in high doses. However, more detailed research is necessary to clarify these concerns.
Some studies suggest that a daily intake of 0.34 mg per pound (0.75 mg per kg) of body weight could be safe. For an individual weighing 154 pounds (70 kg), this would equate to around 53 mg of zeaxanthin per day.
Reaching such high levels through diet alone is typically challenging, as the average daily intake of zeaxanthin from food is approximately 1.3 mg.
Further studies are essential to determine the safe and beneficial dosage of zeaxanthin, especially when it comes to supplements.
Summary: While generally considered safe, further research is required to determine the precise safe dosage limits for zeaxanthin.
Summary
Zeaxanthin is a crucial carotenoid found in your eyes, playing a vital role in protecting them from damage over your lifespan. It’s a fat-soluble substance and part of the carotenoid family.
It’s one of the few carotenoids present in the human eye that absorbs harmful blue light. It also provides antioxidant and anti-inflammatory benefits, reducing the risk of conditions such as age-related macular degeneration, glaucoma, cataracts, and diabetic retinopathy.
Zeaxanthin can be sourced from a variety of whole foods and supplements.
While there’s no officially recommended daily intake for zeaxanthin yet, more research is ongoing to identify safe and beneficial dosages for human consumption.
Suggested read: Alpha-lipoic acid: Weight loss, other benefits, and side effects
Pro tip: Enhance your zeaxanthin intake through a diet rich in dark leafy greens, nutritious fats like pistachios, and egg yolks.
