Lutein is an important vital substance for maintaining your eyesight. A lack of lutein increases the risk of age-related macular degeneration (AMD) or clouding of the lenses (cataracts). Lutein also promotes beauty from within by increasing the skin's elasticity and hydration level.
Lutein is an important, natural antioxidant that helps keep eyes and skin healthy as we age.
Lutein is a carotenoid found naturally in egg yolks, fruits and vegetables - especially dark, leafy vegetables like spinach and cabbage. Carotenoids are ingredients that give plants their colour and act as antioxidants.
Why is it important to include lutein in your diet?
Lutein supports our eyes and skin - the only organs in the body that come into direct contact with the outside world.
Lutein is an antioxidant that suppresses and reduces harmful free radicals, which can play a role in various chronic diseases.
Lutein also filters high-energy, blue wave lengths from the spectrum of visible light. Blue light, from both lighting and the sun, is believed to cause oxidative stress and possible damages caused by free radicals in the human organs that are exposed to this light - for example, the eyes and the skin. Research shows that lutein, along with zeaxanthin, can reduce the intensity of blue light in the retina by up to 90%, which could significantly reduce oxidative damages.
Can the body produce lutein?
No. Lutein is an important compound in the human body, but the body can't produce lutein. Consuming foods or taking supplements that contain lutein is the only way to get lutein into the body.
Lutein is found in the eyes, blood serum, skin, cervix, brain and chest. In the eye, lutein is most concentrated in the macular region of the retina and it is found in smaller amounts throughout the retina, iris, ciliary body and the lens.
How much lutein do you need a day?
You should consume at least 6 - 10 mg of lutein per day. Research shows that 6 - 10 mg of lutein from dark leafy vegetables or other sources is necessary to benefit from the health benefits of lutein. Even if you have a balanced diet, you would have to eat a large bowl of fresh spinach every day to get 6 mg of lutein.
Most people do not eat enough foods that are high in lutein. Statistics show that only 23% of Americans eat the recommended amounts of fruits and vegetables a day.
By taking lutein as a dietary supplement with your meals every day, you get the extra lutein that is equivalent to that in spinach, making your diet even better for your eyes and skin.
What are the differences between free lutein and lutein esters?
Free lutein is the same as that found in leafy green vegetables - the largest source of lutein in our diet. Lutein esters are mainly found in low concentrations in fruits and are sometimes used in products instead of free lutein.
- Chemically speaking, lutein esters differ from free lutein and require enzymatic digestion in the small intestine so that the lutein can be absorbed by the body.
- Free lutein is absorbed directly by the body without enzymatic digestion. You can recognize products that contain lutein from lutein esters by the list of ingredients in the respective product.
How does lutein affect the eye health?
Studies have shown that lutein can reduce the risk of age-related macular degeneration (AMD). A recent study of veterans with AMD shows that 10 mg of lutein can improve the eyesight in people with AMD. Other research reports show that lutein may play a role in reducing the risk of cataracts.
What is age-related macular degeneration (AMD)?
Macular degeneration is a disease that develops with age and usually doesn't appear until later in life. Macular degeneration is the main cause of vision loss in people over the age of 65 and affects the macula lutea - also known as the yellow spot - the point of the sharpest vision of the retina.
It occurs when the retinal cells (rods and cones) in the macula degenerate, resulting in loss of vision in the central area of vision, which does not affect the peripheral vision.
1. "Dry" age-related macular degeneration
The dry AMD occurs in 90 percent of known cases and is characterized by small yellow dots behind the macula, which are called drusen.
These deposits of metabolic end products, as well as an impaired blood flow of the choroid, lead to blindness in only 5 - 10% of cases, but in advanced stages, they lead to a loss of visual acuity due to the extensive cell death of the retinal pigment epithelium.
However, if it is left untreated, it could develop into wet AMD in around 15% of affected persons. A recent study shows that lutein supplements have a positive effect on the eyesight in people with dry AMD.
2. "Wet" age-related macular degeneration
In "wet AMD", new small vessels form as a result of the poor metabolic status to improve the local supply of the retina. These new vessels come from the deeper choroid membrane and go towards the retina.
This can lead to the detachment of the retina. In addition to this, more fluid enters the surrounding tissues, which can lead to scarring.
This process is faster than the process with dry macular degeneration. The perception of distortions is typical for wet AMD, for example when edges are no longer straight but rather distorted.
What is the macula?
The macula lutea, or yellow spot, is a small area that is only two millimetres wide and is located in the back of the eye in the centre of the retina. The middle part of the macula is called the fovea and contains the highest concentration of rod and cone cells. It is responsible for the central vision.
How is lutein related to macular degeneration?
Lutein enters the macula of the eye through the amount of lutein ingested through food.
Lutein filters blue light and can protect the macula from free radical damage. A healthy macula provides good central vision. After years of exposure to light and other stress factors, the macula deteriorates, which can lead to age-related macular degeneration (AMD).
By consuming enough fruits and vegetables, you can consume enough amounts of lutein to reduce the risk of AMD. However, statistics show that, for example, only 23 percent of Americans consume the recommended amount of fruits and vegetables per day.
Therefore, supplementing with lutein is a sure-fire way to get the necessary amount of lutein on a daily basis.
Who is prone to age-related macular degeneration?
There are several factors that can increase your risk of AMD: Age, a poor diet, sunlight, smoking, genes, gender, race, eye colour, alcohol use and heart diseases. For example, people with blue or green eyes, seniors, women, smokers and Caucasians are at higher risk.
What can I do to protect myself from age-related macular degeneration?
While there are factors you can't change - such as age, genes and gender - some important risk factors are lifestyle-related.
Here are some tips:
- Become a non-smoker.
- Wear sunglasses and hats with a large brim to protect yourself from direct or reflected sunlight.
- Consume plenty of fruits and dark, leafy vegetables that contain lutein.
- Limit your consumption of alcohol, saturated fat and cholesterol.
Does lutein also protect against other age-related eye diseases?
The Beaver Dam Eye Study, in which adults ages 43 - 84 participated, shows that taking lutein and zeaxanthin can reduce the occurrence of cataracts.
Cataracts are characterized by a clouding of the lens and are often associated with the ageing process. Lutein and zeaxanthin are the only carotenoids found in the lens.
From 1980 to 1992, Chasan-Taber and co-workers conducted a prospective study on 77,466 female nurses aged 45 to 71 years.
- The results showed that the nurses with the highest intake of lutein and zeaxanthin had a 22 percent lower risk of cataract extractions than those with the lowest intake.
- This study also showed that a high consumption of spinach and cabbage can reduce the risk of cataract extractions. Both spinach and cabbage are high in lutein.
In a similar study, Brown and co-workers examined the connection between the ingestion of carotenoids (alpha-carotene, beta-carotene, lutein, beta-cryptoxanthin and lycopene) and vitamin A and cataract extractions in 36,344 male health professionals aged 45 to 75 years. The study showed that the men with the highest consumption of lutein and zeaxanthin had a 19 percent lower risk of cataract extractions than the men with the lowest consumption.
Also, of the high-carotenoid foods consumed, broccoli and spinach were most strongly associated with a lower risk of cataracts. These vegetables contain a lot of lutein.
In addition to AMD and cataracts, studies also show that lutein has an impact on skin health, cardiovascular health and women's health.
Lutein and the skin
Damage due to environmental influences occurs in all layers of the skin.
The shorter wavelengths of ultraviolet light (UVB) only penetrate the outermost layers of the skin (the epidermis or cuticle). The longer wavelengths (UVA) penetrate the epidermis as well as the dermis (sclera).
Visible light can penetrate the entire skin. Therefore, light can cause damage all over the skin. This damage is related to the depletion of the skin's natural antioxidant system.
Lutein occurs naturally in our skin, just as it does in our eyes. Research shows that lutein can play a role in maintaining healthy skin.
- A recent clinical study performed on humans, showed that 10 mg of free lutein per day increased skin moisture and elasticity and decreased skin lipid peroxidation.
- Lipids are oily components of the skin that are essential for a healthy complexion. They also act as a barrier that slows down the skin's moisture loss.
- This is the first study that showed skin health improvements which solely comes from lutein supplements.
- Lutein which is applied topically to the skin showed significant improvements in these categories and gave even better results when combined with oral lutein supplements.
Lutein and cardiovascular health
The heart protecting role of carotenoids is based on the findings of epidemiological studies, which state that people who consume more fruits and vegetables have a reduced risk of coronary artery diseases and strokes. Residents of the Mediterranean region have the lowest death rates caused by coronary artery diseases in Europe. When the carotenoid content of foods, which are important components of the Mediterranean diet, was analysed, large amounts of lutein were found, which correlated with the relatively high levels of lutein in the blood of Greeks.
The authors of this study suggest that this may contribute to the low death rate from heart disease in this group. The exact mechanisms of the link between lutein and cardiovascular health are not yet entirely clear.
Three studies (collectively known as The Los Angeles Atherosclerosis Study) conducted by Dr. James Dwyer at the University of Southern California show that the protective effect of lutein is partially based on an antioxidant mechanism.
- Firstly, Dr. Dwyer found that the intima-media thickness of the carotid artery decreased in women and men the higher the lutein concentration in the blood plasma was. The intima-media thickness of the carotid artery has been strongly linked to the risk of heart diseases and strokes.
- Secondly, he incubated endothelial and smooth muscle cells from human arteries with lutein and found that monocytes' inflammatory response to LDL (low-density lipoprotein) trapped in the arterial wall was severely inhibited. Finally, Dr. Dwyer's research showed that ingestion of lutein supplements by mice who developed severe arteriosclerotic lesions significantly reduced the size of those arteriosclerotic lesions in the aortic arch.
- In addition to this, lutein reduced significant markers of oxidative stress and the levels of VLDL + IDL (Very Low Density Lipoprotein + Intermediate Density Lipoprotein) in the blood plasma. These results show that lutein could have a positive effect on the progression of early arteriosclerosis.
Lutein and women's health/infant health
Lutein has been detected in both breast tissue and uterine/ovarian tissue. Other functions of lutein in the body that are currently being investigated include the effect of lutein on pregnancy and breastfeeding.
Studies have shown that the lutein levels in the blood plasma increase during pregnancy, although the reasons for this are not yet known.
Lutein has also been found in the umbilical cord blood after birth and exists in the colostrum (first milk in mammals) and mature breast milk. It has been theorized that lutein could be actively excreted in breast milk. This is based on the findings, that the lutein and beta-carotene levels in the blood serum are the same, but the lutein levels in breast milk are significantly higher than the beta-carotene levels.