Zeaxanthin is a common carotenoid, a pigment found in high levels in dark green vegetables, orange and yellow fruits, and egg yolks. It is also one of only two carotenoids found in the human eye, where it helps protect the eyes from the harmful effects of oxidation and light.
Carotenoids act as antioxidants, substances that protect the body’s cells from damage. They are also thought to have cancer-fighting properties.
This article explains how zeaxanthin works, the benefits it may have for eye health, and how people take its supplement form.
Benefits of Zeaxanthin
Zeaxanthin plays two important roles:
Dietary supplements are not regulated like drugs in the United States, meaning the Food and Drug Administration (FDA) does not approve them for safety and effectiveness before products are marketed. When possible, choose a supplement that has been tested by a trusted third party, such as USP, ConsumerLabs, or NSF. However, even if supplements are third-party tested, that doesn’t mean that they are necessarily safe for all people or effective in general. It is important to talk to your healthcare provider about any supplements you plan to take and to check in about any potential interactions with other supplements or medications.
Supplement Facts
Active ingredient: ZeaxanthinLegal status: Available over the counterSuggested dose: 2 milligrams (mg) per daySafety considerations: Long-term safety has not been established
It builds a yellow-colored pigment shield to protect eye cells from the harmful effects of certain light sources, such as the sun.It protects the eyes from dangerous free radicals, unstable molecules that steal electrons from healthy cells, causing damage (what’s known as oxidation).
Once inside the body, zeaxanthin is drawn to the eyes. It makes its way into the lens (the clear, curved structure toward the front of the eye), as well as the macula and fovea—both parts of the retina, or tissue that lines the back of the eyeball.
The macula is the most sensitive part of the retina and the one with the most photoreceptors. These are special cells that convert light into signals that can be interpreted by your brain. As such, the macula is the place where your sharpest vision is produced. It is also responsible for your ability to perceive colors.
Zeaxanthin and another carotenoid called lutein are the only dietary carotenoids that accumulate in the retina. Because both zeaxanthin and lutein are found in large amounts in the macula, they’re known as macular pigments.
Uses For Zeaxanthin
Research suggests that zeaxanthin may help delay or prevent the progression of eye diseases such as cataracts and age-related macular degeneration (AMD), the leading causes of visual impairment and acquired blindness in the United States.
Macular Pigment and Blue Light
Macular pigment works to filter blue light, the visible light at the end of the color spectrum that researchers believe can cause macular degeneration. Further research is needed to prove the harmful effects of blue light. However, studies have shown that by filtering blue light, macular pigment helps improve several areas of vision including:
Supplement use should be individualized and vetted by a healthcare professional, such as a registered dietitian, pharmacist, or doctor. No supplement is intended to treat, cure, or prevent disease.
Age-Related Macular Degeneration (AMD)
Some of the dietary sources of zeaxanthin have been studied as protective factors in AMD, which affects people age 65 and older.
A 2012 meta-analysis found that a diet rich in lutein and zeaxanthin reduced the risk of progressing from early- to late-stage AMD by 26%. It also helped reduce the risk of developing early-stage AMD by about 4%.
Similarly, a 2017 review found that lutein and zeaxanthin obtained through both dietary sources and supplementation could protect the eyes against the progression of AMD.
A more severe form of macular degeneration, wet AMD, occurs when the blood vessels in the macula grow and leak fluid. Dry AMD is one risk factor for wet AMD, but there are other risk factors too, such as high blood pressure.
According to the American Academy of Ophthalmology, zeaxanthin may be beneficial for preventing the progression of both types of AMD.
Cataracts
Zeaxanthin and lutein consumption may slow the formation of cataracts, which cause blurry vision.
A 2017 review found that higher concentrations of lutein and zeaxanthin in the blood were associated with a reduced risk of a type of cataract called nuclear cataract, although the evidence that lutein and zeaxanthin can help reduce the risk of other types of cataracts is insufficient at this time.
Uveitis
Uveitis is an inflammation or swelling of the eye’s uvea. The uvea is located in the center of the eye and is responsible for supplying blood to the retina. Lutein and zeaxanthin may aid in slowing this inflammatory process.
A 2015 in vitro study found that lutein and zeaxanthin had anti-inflammatory effects on human uveal cells. It’s important to note, however, that this study was conducted on cells in a lab, so it’s impossible to know if these effects would also happen in the human body.
More high-quality studies using lutein and zeaxanthin would need to be done on humans before further conclusions about their effectiveness for uveitis can be drawn.
Diabetic Retinopathy
Diabetic retinopathy is a complication of diabetes in which uncontrolled blood sugar causes damage to blood vessels in the retina. Lutein and zeaxanthin may reduce the oxidation processes that damage the eyes in this way.
A 2015 review looked at a series of animal studies that evaluated the effects lutein and zeaxanthin on diabetic mice and rats. It concluded that lutein and zeaxanthin had a protective effect against retinal changes associated with diabetes.
Again, though, because these studies were done on rodents, there’s no proof that these effects would also happen with humans.
What Are the Side Effects of Zeaxanthin?
Researchers have found no side effects from or negative interactions with zeaxanthin. Although, people with fair skin may develop a yellowish coloration of the skin if they exceed the maximum daily recommended dosage for adults (10 mg).
Precautions
On a daily basis, there doesn’t seem to be a risk of taking too much lutein and zeaxanthin via supplements or through diet.
While zeaxanthin supplements have not been found to cause any adverse side effects, no studies have been done on their long-term use. In fact, researchers can’t be certain whether taking a synthetic form of zeaxanthin is okay for more than five years. Thus, zeaxanthin supplements are only recommended for those who have a significant and immediate concern about vision loss getting worse.
If you are looking for a decades-long plan to support eye health, focus on eating fruits and vegetables every day.
Dosage: How Much Zeaxanthin Should I Take?
Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs.
Generally, health experts recommend that adults eat five servings of fruits and vegetables every day, which should provide about 5 mg of carotenoids (including zeaxanthin and lutein).
But most people don’t eat this many servings, putting the average intake of carotenoids closer to 2 mg per day. This means supplements may be helpful to ensure you get an adequate amount of zeaxanthin.
Studies show that a daily supplement of 2 mg zeaxanthin can be beneficial for vision.
Zeaxanthin, along with lutein, can be taken at any time of day, but mealtime is usually best. As a fat-soluble antioxidant, zeaxanthin requires some fat to be properly absorbed.
What Happens If I Take Too Much Zeaxanthin?
Zeaxanthin can be safely taken at higher doses. Studies have shown, for instance, that taking 20 mg daily for up to six months should cause no problems.
Try sprinkling olive oil on your vegetables to help ensure that you get the full benefits of the zeaxanthin they contain. Or, if taking a supplement, do so with food.
Sources of Zeaxanthin and What to Look For
If you have not been diagnosed with macular degeneration, health experts recommend that you increase your intake of zeaxanthin by eating more foods rich in this micronutrient. This recommendation includes people who may be at risk for AMD, such as family members of those who have been diagnosed or smokers, who are four times more likely to develop AMD than those who have never smoked.
Frequently Asked Questions
- Does zeaxanthin benefit parts of the body besides the eyes?
- Daily zeaxanthin consumption may protect skin cells from premature aging as well as UVB-induced tumors. A research study showed that consuming 10 mg of lutein and 2 mg of zeaxanthin a day may also improve skin tone.
- Learn More:
- Reducing Signs of Aging Skin
- What is the difference between zeaxanthin and meso-zeaxanthin?
- Meso-zeaxanthin is a form of zeaxanthin that’s predominantly found in the direct center of the macula. Zeaxanthin, lutein, and meso-zeaxanthin together form macular pigment, the natural blue light filter and antioxidant present in the retina.
- Are zeaxanthin and astaxanthin the same thing?
- No. They’re both carotenoids, pigment compounds that give fruits, vegetables, and seafood their vibrant colors, but zeaxanthin is a yellow pigment and astaxanthin is a red one.
- What is the difference between lutein and zeaxanthin?
- Both are important antioxidants, but they play different roles. Zeaxanthin is found mostly in the center of the eye’s macula, while lutein is mainly in the surrounding retina.
- What is the best source of zeaxanthin?
- Eggs may be your best source. While some vegetables contain more zeaxanthin, your body’s better able to use what it gets from an egg, possibly because of its fat content, which helps with absorption.
Daily zeaxanthin consumption may protect skin cells from premature aging as well as UVB-induced tumors. A research study showed that consuming 10 mg of lutein and 2 mg of zeaxanthin a day may also improve skin tone.
Meso-zeaxanthin is a form of zeaxanthin that’s predominantly found in the direct center of the macula. Zeaxanthin, lutein, and meso-zeaxanthin together form macular pigment, the natural blue light filter and antioxidant present in the retina.
No. They’re both carotenoids, pigment compounds that give fruits, vegetables, and seafood their vibrant colors, but zeaxanthin is a yellow pigment and astaxanthin is a red one.
Both are important antioxidants, but they play different roles. Zeaxanthin is found mostly in the center of the eye’s macula, while lutein is mainly in the surrounding retina.
Eggs may be your best source. While some vegetables contain more zeaxanthin, your body’s better able to use what it gets from an egg, possibly because of its fat content, which helps with absorption.
Expanding your diet to include carotenoid-rich foods is one promising way to protect your eyes from disease, according to the American Optometric Association.
Food Sources of Zeaxanthin
If you are looking to boost your zeaxanthin intake, look for green, leafy vegetables since they have the highest amount of the carotenoid. In fact, zeaxanthin is the reason these foods are richly colored since it modulates light energy and keeps chlorophyll at appropriate levels during photosynthesis. The chlorophyll in dark green vegetables actually masks the lutein and zeaxanthin pigments, giving the vegetables their recognizable green color.
But you shouldn’t limit yourself to just a few veggies. In addition to greens, eggs and brightly colored fruits and vegetables are also a good source of both zeaxanthin and lutein.
Among the foods that provide the carotenoids you need for eye health are:
- EggsKaleSpinachSwiss chardRomaine lettuceMustard greensTurnip greensCollardsWatercressGreen peasSummer squashPumpkin
Zeaxanthin Supplements
Be aware that dietary supplements are not regulated by the FDA to the extent that pharmaceuticals are, other than to prohibit unsupported health claims. No health claims have been approved by the FDA or the European Food Safety Authority (EFSA) for zeaxanthin supplements.
If you’re trying to add more zeaxanthin and lutein to your diet, try jazzing things up with broccoli rabe with pine nuts; pumpkin mousse; salmon with mango salsa; sunset gazpacho; or a veggie frittata with orange pepper, spinach, and sundried tomatoes.
Several groups are trying to fill the shoes of the FDA with regard to supplements, including ConsumerLab.com, NSF International, and U.S. Pharmacopeia (USP). USP, a nonprofit, has set standards for supplements that Consumer Reports says are the most widely accepted.
Summary
Zeaxanthin is a carotenoid, a type of pigment that gives orange and yellow fruits and vegetables their vibrant colors. Along with the carotenoid lutein, zeaxanthin can help delay and even prevent the progression of cataracts and age-related macular degeneration. If you’ve been diagnosed with vision loss and can’t get between 6 mg and 10 mg of the two carotenoids from your diet, consider taking a supplement to fill the gap.
USP publishes the Dietary Supplements Compendium, an online, subscription-based database that provides quality standards for the production of dietary supplements. Those thatpass USP’s quality requirements are awarded a distinction called the USP Verified Mark.
A Word From Verywell
Besides eating at least five portions of fruits and vegetables a day, being physically active and refraining from smoking will improve your health, and, by extension, keep your eyes healthy. To protect your eyes from damage, wear sunglasses or protective eyewear when it’s smart to do so, rest your eyes from heavy-duty computer work every 20 minutes, and be proactive about preventing eye infections if you wear contact lenses.