Zeaxanthin: Get to Know This Protective Pigment

Zeaxanthin. This alien-sounding name belongs to a plant pigment that plays an important role in photosynthesis. In humans, following ingestion, the molecule accumulates in the eye, where it helps to absorb certain wavelengths of light. Now, researchers are testing the compound against a range of health conditions.

What is zeaxanthin?

Zeaxanthin plays an important biological role in plants, but it also exhibits beneficial functions in certain areas of the human body, particularly the eyes. As a plant pigment, zeaxanthin underpins the bright colours of bell peppers, goji berries, and other fruits. Animals, including humans, don’t have the enzymatic machinery capable of making zeaxanthin, and therefore must consume certain foods to acquire this molecule. In the body, zeaxanthin exerts actions as an antioxidant, quelling DNA-damaging free radicals, and it protects the eyes from age-related degeneration.

Zeaxanthin is one of the most common molecules in the chemical class known as carotenoids, alongside beta-carotene, lutein, and lycopene. Over 600 of these pigments exist in the plant kingdom, and they are divided into two groups: carotenes and xanthophylls. Because the zeaxanthin molecule contains oxygen instead of only hydrogen and carbon, it belongs to the latter group.

When thinking about photosynthesis, we mostly attribute the green pigment chlorophyll to the light-harvesting process. However, the orange, red, purple, and yellow pigments that make up the carotenoids also contribute to the process. Moreover, carotenoids shield plants against overexposure to sunlight through a process called photo-protection. Zeaxanthin also works as a photo-protective agent in certain forms of algae, which are fundamental to the health of oceans and form the energy base of all aquatic life forms.

This mechanism of photo-protection also trickles over to the human body. When we consume sources of zeaxanthin, the molecule accumulates in the eyes. Here, it serves as a light filter that helps to protect our visual organs from sunlight damage. Ongoing research is also probing the plant pigment for its effects on cardiovascular, liver, and skin health.

What foods contain zeaxanthin?

Zeaxanthin chiefly occurs in plants, but some animal products also contain the pigment. The foods highest in the molecule include:

• Spinach
• Green peas
• Sweet corn
• Red grapes
​​• Kale
• Parsley
• Coriander
​​• Pistachios
• Goji berries
• Carrots
​​• Pumpkins
• Eggs

What are the health benefits of zeaxanthin?

While many of the studies on zeaxanthin’s potential benefits have been in vitro, several human trials also exist. Below, we examine some of the most impactful research on the subject, but it’s important to remember that studies surrounding zeaxanthin are generally preliminary and ongoing.

Eye health

The carotenoids zeaxanthin, meso-zeaxanthin, and lutein are categorised as macular xanthophylls. These fat-soluble compounds accumulate in regions of the eye called the macula lutea and the eye lens. Here, they help to shield our delicate visual apparatus from the dangers of sunlight. Without natural light, our species (and many others) wouldn’t have come into being. However, certain wavelengths of light can damage the eyes. Consuming plants high in macular xanthophylls could work as a buffer against light that would otherwise result in photochemical damage. Research shows that ocular carotenoids are capable of absorbing light within the visible ranges of 400–500nm, suggesting they’re capable of shielding the retina and lens.^[1]

Antioxidant properties

Aside from buffering against select wavelengths of light, zeaxanthin could help to protect the eyes through another means: by quelling inflammatory cascades. Prolonged exposure to light gives rise to oxidative stress within the eyes. This causes a reaction that results in DNA damage and inflammatory apoptosis (the controlled death of cells), subsequently causing cell damage, retinal ageing, and the progression of age-related macular degeneration. Studies show that zeaxanthin could help to protect against these processes through its antioxidant activity. This molecule gets ferried to the retinal membrane, where it helps to protect the retina and prevent age-related macular degeneration.

Liver health

Zeaxanthin dipalmitate (ZD) is another natural carotenoid that shows up in high concentrations in certain fruits. This molecule has shown some serious potential when it comes to protecting our major organ of detoxification: the liver. Our liver receives the brunt of most of our poor lifestyle habits, especially the excess consumption of alcohol. Over time, excess assault on the liver can cause a range of health issues, including liver disease, reduced hepatic function, and fibrosis. Studies are continuing to test ZD in models of alcoholic fatty liver disease. Researchers are looking for positive changes in oxidative stress, inflammation, liver cancer, and acute liver injury.^[2]

Heart health

According to the World Health Organization, ischaemic heart disease ranks as the number one cause of death throughout the world, resulting in just under 9 million deaths in 2019 alone.^[3] Various risk factors contribute to the condition, including obesity, smoking, high blood pressure, and a lack of physical activity. Interestingly, alongside other lifestyle interventions, zeaxanthin could help to improve overall heart health. While research remains early, studies show that higher plasma levels of zeaxanthin could protect against early atherosclerosis—a hardening of the arteries that can increase the risk of a heart attack.^[4]

Skin health

As the second-largest organ in the body, the skin provides a semi-impermeable shield that protects the body against innumerable microbial pathogens and prevents fluid loss. While most of us understand the importance of our skin, many of us fail to stick to daily regimens to keep it hydrated and healthy. Myriad products use components such as vitamin E, hyaluronic acid, and shea butter to improve the way our skin feels. Soon, we could see zeaxanthin included in more cosmetic products. Studies are testing the compound to see if it can improve skin hydration and wrinkle count.^[5] Other investigations are testing the pigment against cell death caused by UV exposure.^[6]

Potential side effects of zeaxanthin

Consuming a diet rich in fresh fruits and vegetables provides the body with zeaxanthin, although some people choose to consume the compound as a supplement. Based on early research, almost everyone can benefit from consuming foods high in zeaxanthin in the interest of eye and heart health. Through diet, most people consume a daily average zeaxanthin intake of 1.3mg. Current research suggests that a dose of up 2mg per day has a good safety profile.^[7] However, doses of up to 10mg per day have shown to be safe when taken for up to one year. Studies have also found a rare side effect of skin discolouration, but this phenomenon doesn’t appear to cause harm.^[8]

How to take zeaxanthin?

There are a host of zeaxanthin supplements available, mostly in the form of tablets or capsules. When and how to take these products depends on their concentration and other ingredients; simply follow product directions. Most of them recommend 2mg by mouth daily—a quantity shown to be safe when taken over relatively long periods. Due to the fat-soluble nature of the compound, taking it alongside a fatty meal will help to optimise absorption. If you're looking for a high-quality zeaxanthin supplement, Cibdol's Focus Better blend provides the compound in an effective nootropic formula.

Key takeaways

Zeaxanthin plays a crucial role in plant physiology. Although not synthesised within the human body, it can also help to protect the eyes by absorbing light when consumed in common foods including vegetables and eggs. Ongoing studies are also exploring if the compound could play a role in liver, heart, and skin health in the future. While most people can obtain enough of the molecule each day through diet, there are plenty of zeaxanthin supplements available as well.

Interested in trying a high-quality zeaxanthin supplement for yourself? Visit the Cibdol store to buy Focus Better. And to learn more about the other ingredients in our range of supplements, browse our Education section.