Colourful Fruits and Vegetables
~ July 2003 No.169 ~
Foods that look good and are good to eat are everyones’s dream. There is nothing more appetizing than a ripe golden peach, bright green spinach or large serving of orange carrots. Look good and good for you. It seems that many of the compounds that give fruits and vegetables their colour are also good for health.
One such compound is lutein or xanthophylls. Lutein is a yellow coloured complex molecule that dissolves in oil (lipid soluble) that belongs to the large family of carotenoid pigments. Lutein cannot be made by the body, and must be obtained from food or vitamin supplements. The best sources of lutein are green leafy vegetables such as spinach, kale, collard greens, romaine lettuce, leeks and peas. It is also found in egg yolk and red peppers.
In the body lutein acts as an antioxidant. The main function of antioxidants is to protect cells against free radicals. Free radicals are formed in the body during many metabolic processes. Free radicals are very chemically reactive and they attack and damage cells and cell structures and are thought to be responsible for many types of cancer.
Lutein is not found in high concentrations in the body except in the eyes. In the eye, lutein is found in the macula which lies in front of the cones in the retina, where it is believed to act as a yellow filter. In 1999, data from the Nurses Health Study (United States) showed a reduced likelihood of cataract surgery with increasing intakes of lutein.
Dietary lutein is thought to be an essential micronutrient for normal vision. Because lutein is fat-soluble, a lutein deficiency may occur if fat digestion and absorption is impaired. This may be particularly important to those who have cut their fat intake. Although fat often has a bad image, it is needed in the diet to permit the absorption of lutein and other fat (lipid) soluble compounds.
Chemical Structure of Lutein
Antioxidants, Zinc, and Age-Related Macular Degeneration
Arch Ophthalmol 2001,119:1533-1534