Lutein

Lutein is a xanthophyll - an oxygen-containing carotenoid. Carotenoids are responsible for the yellow, orange and red pigments in food. They are considered essential nutrients, as the body cannot produce them itself and they must therefore be supplied with food.there are two types of carotenoids. Xanthophylls, which contain oxygen and usually contribute to yellow pigments, and carotenoids, which do not contain oxygen and usually contribute to orange pigments.

Lutein is found in the retina of the eye together with the xanthophyll zeaxanthin. Because these carotenoids are found in high concentrations in the back of the eye, they are also known as macular pigments and may be beneficial for eye health. Lutein has mild antioxidant properties that may play a role in cognitive function, heart health and the prevention of certain cancers, although further studies are needed.

Can lutein protect the eyes from degenerative processes?

This is the site of sharpest vision, and as we age, degenerative processes can develop here. As a result, this can eventually lead to vision loss. Age-related macular degeneration is one of the most important causes of vision loss in old age. It is attributed to decades of exposure to light and oxygen, which can increase the occurrence of free radicals. Lutein acts like a filter, protecting the macula from the harmful effects of light (UV light). It also helps to break down free radicals in the eye area. In this way, lutein can prevent age-related degeneration of the macula and also slow down its progression.

In studies, a supplement containing lutein and zeaxanthin was able to reduce the progression of macular degeneration by 25% over 5 years in people suffering from macular degeneration. In people without macular degeneration, this supplement did not prevent the onset of the disease (1). Beta carotene, another carotenoid associated with eye health, was previously used as a supplement until it was found to increase the risk of lung cancer in smokers, and switching from beta carotene to lutein and zeaxanthin has been shown to be just as beneficial for eye health without increasing the risk of lung cancer (2).

Another benefit to eye health is that lutein is an antioxidant. Inflammation and oxidative stress are linked to eye diseases such as glaucoma, diabetic retinopathy and macular degeneration. Lutein has antioxidant properties and studies have found it to be effective in preventing these eye diseases (3). In addition to this, research suggests that lutein is important for the development of babies' eyes during pregnancy and for lifelong vision, although further research is needed to find the optimal dosage for pregnant and breastfeeding women (4). Finally, lutein may be an effective treatment for dry eyes, although further studies are needed in this area (5).lutein may also help prevent cataracts. Although a deficiency of lutein has not yet been clearly proven, people who consume more lutein have a lower risk of macular degeneration.

Can lutein promote heart health?

High dietary lutein intake and high circulating lutein levels are associated with better heart health (6). One study linked lutein and zeaxanthin to improvements in clinical markers in patients with heart disease. The scientists believe that the anti-inflammatory properties of these compounds were responsible for this and recommended further research in this area (7). Another study found that daily supplementation with 20 mg of lutein over a 3-month period was associated with reduced cholesterol and triglyceride levels, both known risk factors for heart disease (8). However, the results of studies on the relationship between lutein and heart health are mixed and some studies have found no correlation at all. For this reason, further studies are needed to determine the role of lutein in heart health (9).

Does lutein have anti-cancer effects?

Lutein, together with other carotenoids, could improve cancer prognosis (10). One study found that a high intake of lutein, along with other nutrients found in fruits and vegetables, was associated with a reduced risk of pancreatic cancer (11). In addition, lutein, along with other carotenoids, may protect against breast cancer and cancer of the neck and head (12). All in all, the research on lutein and its cancer benefits is promising, but not definitive, so further studies are needed (13).

Does lutein have positive effects on brain health?

Scientific research suggests that high intakes and high circulating levels of lutein are associated with better cognitive performance and improved memory (14). One study found that a daily supplement of lutein, zeaxanthin and meso-zeaxanthin was effective in improving memory performance over the course of a year (15). Carotenoids in general may play a protective role in preventing neurodegenerative diseases, meaning they could help promote brain health in older age, although the evidence is mixed (16). A study published in 2014 found that people who took a daily lutein supplement were able to respond more quickly to visual information than people who did not supplement with lutein (17).

Can lutein reduce the risk of diabetes?

In addition to the benefits for eye and heart health, lutein may reduce the risk of developing diabetes. Some studies conducted in animals suggest that high levels of lutein in the diet and blood may reduce the risk of developing diabetes. It is known that people with low blood glucose levels have a lower risk of developing diabetes. In a study conducted in 2000 with diabetic rats, it was observed that lutein supplementation helped to normalize blood glucose levels (18). In addition, less oxidative stress and better vision were observed in the rats that received lutein.

Can lutein protect the skin?

Lutein and zeaxanthin may have beneficial properties for the skin. The antioxidant properties of these two compounds may help protect the skin from damage caused by the sun's UV rays (19). In one study, rats fed a diet enriched with 0.4% lutein and zeaxanthin showed less UVB-induced skin damage than rats fed a diet enriched with only 0.04% of these two compounds (29). In addition, lutein and zeaxanthin have been shown to protect proteins, fats and DNA from stressors while helping the body to recycle the body's most powerful antioxidant called glutathione (21).

What are the best food sources of lutein?

Lutein is generally found in green leafy vegetables and yellow pigmented foods. Since lutein is a fat-soluble nutrient, lutein-rich foods should be consumed with some fat to improve the absorption of lutein in the body.

Foods rich in lutein include (23):

Egg yolk (one of the most absorbable sources due to its fat content)
basil
parsley
Green leafy vegetables such as spinach, kale, broccoli and lettuce
Yellow corn
Red grapes
Durum wheat
Peas

What lutein supplements are available?

The typical diet provides 1 to 3 mg of lutein per day, with most benefits observed at an intake of 6 mg per day, which is achievable through a targeted diet. Most supplements contain 20 mg of lutein or more, which is more than is needed to reap the benefits of lutein. Most studies have used dosages in the range of 10 to 40 mg of lutein per day with no adverse side effects observed (23).

How much lutein is recommended for prevention?

For prevention, 6 mg of lutein per day is recommended. Lutein supplements are best taken with meals and with fatty foods, which may improve absorption.

Does lutein have any side effects?

Lutein is probably safe and harmless for most people. Even a high dietary intake of lutein of 6.9 to 11.7 mg per day appears to be safe and harmless. Lutein supplements providing 10 mg of lutein per day have also been used safely. However, a high intake of xanthophyllins in general has been associated with an increased risk of skin and stomach cancer. Although the results of these studies are not considered significant, further research is needed to determine safe and optimal dosages of xanthophyllins such as lutein (23).