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Page 180
| Carotenoids |
| Carotenoids can protect phagocytic cells from auto-oxidative damage, enhance T- and B-lymphocyte proliferate responses, and enhance macrophage, cytotoxic T-cell, and natural killer-cell tumoricidal capacities, as well as increase the production of certain interleukins. Carotenoids protect the body, especially the lipids and organ walls in the cell, from oxidative damage. |
| The carotenoid family contains over eight hundred different members, each with a slightly different molecular structure and physical properties. It is best to consume a full spectrum of carotenoid pigments. There are two main types of carotenoids. One type contains no oxygen and has provitamin A abilities, which means that it can remain in the body as carotene but can be convened into vitamin A upon demand. Examples of this type of carotenoid, such as beta-carotene arid the recently popular lycopene found abundantly in tomatoes, are typically orange/red in color. |
| The other type of carotenoid, called xanthophyll, has no provitamin A conversion abilities. Xanthophyll-rich carotenoids are primarily yellow in color and include many flowers, such as calendula, as well as the spice saffron. The color changes we see in ripening fruit or the leaves turning in the fall is the result of carotenoid pigments emerging after being masked by green chlorophyll pigments. Lutein, found in green leafy vegetables, capsanthin, and canthaxanthin are other examples of xanthophyll carotenoids. Carotenoids protect the epithelial tissue (skin, stomach, and lungs) from becoming cancerous. The carotenoid lycopene has been shown to be useful in treating pancreatic cancer 9 and in reducing the risk of prostate cancer.10 |
| Beta-carotene and canthaxanthin have been shown to protect animals against three types of tumors: UV-induced skin tumors, carcinogen-induced skin tumor, and UV plus carcinogen-induced skin tumors.11 Evidence continues to accumulate that carotenoids may possess intrinsic chemopreventive action with respect to damage of the nucleus, malignant transformation, and tumor formation. |
| Recent studies have also shown that beta-carotene and canthaxanthin can inhibit neoplastic transformation by enhancing normal cellular communication. This mode of action is referred to as gap junctional communication. Enhanced communication leads to decreased proliferation, whereas a low level of communication is associated with high proliferation rates. Junctional communication has many similarities to the effects of tumor-suppressor genes.12 |
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