Lutein, also known as "plant lutein", coexists with zeaxanthin in nature. It is the main component of plant pigments such as corn, vegetables, fruits, and flowers. It is contained in the chloroplasts of leaves and can transfer the absorbed light energy to chlorophyll a. It is speculated that it has a protective effect against photooxidation and photodamage. It is also the main pigment that constitutes the macular area of the human eye retina.
Overview of Existence
Lutein is a natural substance widely found in vegetables, flowers, fruits and other plants. It belongs to the "carotenoid" family. It is currently known that there are more than 600 carotenoids in nature, of which only about 20 exist in human blood and tissues. The carotenoids found in the human body mainly include d-carotene, p-carotene, cryptoxanthin, lutein, lycopene and ortho-xanthin.
Medical experiments have shown that natural lutein contained in plants is an excellent antioxidant. Adding a certain amount of lutein to food can prevent cell aging and organ aging, and can also prevent vision loss and blindness caused by age-related macular degeneration. Through a series of medical studies, carotenoids have been suggested as cancer preventives, life extenders, ulcer inhibitors, heart attacks and coronary artery disease inhibitors. At the same time, lutein can also be used as a feed additive for the coloring of poultry meat and eggs, and has also been used as a coloring and nutritional health agent in the food industry.
Function of Lutein
Lutein is an important antioxidant and a member of the carotenoid family (a group of natural fat-soluble pigments found in plants). It is also known as "plant lutein" and coexists with zeaxanthin in nature.
(1) Main pigment components of the retina: Lutein and zeaxanthin constitute the main components of plant pigments such as vegetables, fruits, and flowers, and are also the main pigments in the macula of the human retina*. Human eyes contain high amounts of lutein, an element that cannot be produced by the human body and must be supplemented by lutein intake. If this element is lacking, the eyes will go blind.
(2) Protect the eyes from light damage, delay eye aging and prevent pathology: Ultraviolet rays and blue light in sunlight enter the eyes and produce a large number of free radicals, leading to cataracts, macular degeneration, and even cancer. Ultraviolet rays can generally be filtered out by the cornea and lens, but blue light can penetrate the eyeball and reach the retina and macula. Lutein in the macula can filter out blue light and prevent blue light from damaging the eyes. The outer fat layer of the macula is particularly susceptible to oxidative damage from sunlight, so this area is prone to degeneration.
(3) Anti-oxidation, helping to prevent cardiovascular sclerosis, coronary heart disease and tumor diseases caused by aging.
Effects of Lutein
1. Protecting eyesight
Lutein plays an important role in protecting the macula in the retina. When it is deficient, it can easily lead to macular degeneration and blurred vision. This can lead to symptoms such as vision degeneration and myopia. Lutein is the precursor of NA and can be converted into VA in the human body. The main physiological function of lutein to the eyes is as an antioxidant and photoprotective agent. The optic nerve cannot be regenerated and is extremely vulnerable to damage by harmful free radicals. The antioxidant effect of lutein can inhibit the formation of harmful free radicals. Lutein can absorb a large amount of blue light. The wavelength of blue visible light is close to that of ultraviolet light, and it is the most potentially harmful type of visible light that can reach the retina. Before reaching the sensitive cells on the retina, the light first passes through the highest concentration area of lutein. At this time, if the lutein content in the macula is rich, this damage can be minimized.
2. Antioxidant effect
The strong oxidative effect of lutein can inhibit the activity of reactive oxygen free radicals and prevent reactive oxygen free radicals from damaging normal cells. Relevant experiments have shown that reactive oxygen free radicals can react with DNA, proteins, and lipids, weakening their physiological functions, and then causing chronic diseases such as cancer, arteriosclerosis, and age-related leukodystrophy. Lutein can inactivate singlet oxygen through physical or chemical quenching, thereby protecting the body from harm and enhancing the body's immune capacity.
3. Reduce the incidence of cataracts
Cataracts are the main eye disease causing blindness worldwide. The latest research shows that the goal of reducing the incidence of cataracts can be achieved by increasing the intake of lutein. It is currently believed that the mechanism is that the lower macular pigment density is closely related to the higher lens visual density of middle-aged and elderly people, and the higher lens visual density is considered to be a significant feature of cataracts.
4. Delaying arteriosclerosis
Recent research results show that lutein has a delaying effect on the early stage of arteriosclerosis. It is mainly the relationship between the change in the thickness of the endothelial membrane of the main artery and the lutein content in the blood. The low lutein content in the blood is very likely to cause thickening of the arterial wall. As the lutein content gradually increases, the thickening trend of the arterial wall decreases, and arterial embolism is also significantly reduced. At the same time, the lutein cord in the arterial wall cells can also reduce the oxidation of LDL cholesterol.
5. Anti-cancer effect
Several studies have shown that lutein has an inhibitory effect on many cancers, such as breast cancer, prostate cancer, colorectal cancer, skin cancer, etc. According to a recent study by the School of Pharmacy at New York University, there is a close relationship between reducing the incidence of breast cancer and lutein intake. The survey found that the incidence of breast cancer in the experimental group with low lutein intake was (2.08-2.21) times that of the group with high intake. This effect may involve indirect immune regulation in coordination with other organs and tissues. The study concluded that lutein intake in the diet can not only inhibit cancer but can even play a role in preventing tumor occurrence. Relevant institutions recommend that an average daily intake of 400 g to 600 g of fruits and vegetables per person can reduce the relative risk of cancer by 50%.
