What Are Carotenoids?

- Lutein, Zeaxanthin, Lycopene, And Carotenes

Carotenoids are an interesting range of nutrients that are getting a lot more positive attention from the scientific world of late. Whilst there are many types of them, it is a certain handful that may prove significant for our health.

There are 563 carotenoids that have been identified (although Wikipedia does say there are over 600). The earliest studied were the carotenes, and other carotenoids that can be made into vitamin A in our body. These compounds include alpha and beta carotene, and beta-cryptoxanthin.

Despite their relationship with vitamin A, having too much carotene is not toxic. Generally, the worst that happens is your skin develops an orange tinge, which goes back to normal when the excess carotene is flushed out by your body's normal elimination processes. Vitamin A, on the other hand, is toxic in large amounts. Because it is a fat soluble vitamin, it builds up in the body if too much is consumed.

The only possible danger known that is associated with carotene is a study that had to be stopped because there appeared to be an increase in the number of lung cancers developing in people who were exposed to asbestos or whose lungs were irritated by smoking. The study participants were taking beta-carotene supplements, however, not getting too much carotene from their diet. Beta-carotene was probably chosen for the trial because it is the most effective at converting into vitamin A compared to alpha carotene and beta-cryptoxanthin.

The carotenoids give plants and organisms (such as algae) their distinctive colors. As the name suggest, these yellow-orange carotene pigments can be found in carrots, as well as other yellow and orange vegetables and fruit.

Carotenes are not the carotenoids that are garnering most of the press lately though. It is their antioxidant cousins, lycopene, lutein and zeaxanthin. Whilst these 3 don't have any provitamin-A activity, they still provide important health benefits.

Lycopene, found in tomatoes, has strong antioxidant activity. It has been linked to

• an increase in iron absorption
• improved eye health
• assistance with chronic diseases

Lycopene is more available to the body when tomatoes are cooked or processed in some way, as in juiced.

Lutein is an intriguing carotenoid that has health benefits beyond eye health, though it is important here too. It:

• provides nutrients for our eyes
• improves skin health in several ways (hydration, elasticity, and lipid content)
• acts as an antioxidant
• filters out a lot of the blue light in indoor light and sunlight that causes oxidative damage
• reduces the risk of age-related macular degeneration
• may help prevent cataracts forming
• has potential cardiovascular benefits

Lutein is found in leafy green vegetables.

Like lutein, zeaxanthin is also found within the retina in our eyes. It has many of the benefits of lutein, though it is in fact found in yellow fruits and vegetables. Examples include corn and saffron. There's some great information on zeaxanthin and AMD here.

• Eye Vitamins And Macular Degeneration
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