The information resource about Nutrients, Probiotics and Food Supplements
Nutrient Details For : Carotenoids

A nutrient is any element or compound necessary for or contributing to an organism's metabolism, growth, or other functioning. Click name for details Arsenic Biotin Boron Calcium Carbohydrates Carnitine Carotenoids Chloride Choline Chromium Copper Energy Fiber Fluoride Folate Iodine Iron Lipids Magnesium Manganese Molybdenum Niacin Nickel Pantothenic acid Phosphorus Phyto-chemicals Potassium Protein Riboflavin Selenium Silicon Sodium Thiamin Vanadium Vitamin A Vitamin B 12 Vitamin B 6 Vitamin C Vitamin D Vitamin E Vitamin K Zinc Further Trace Elements

There are over 600 carotenoids in nature. Carotenoids generally are efficient in absorbing light, and are the major yellow and red pigments in many fruits and vegetables.
Beta-carotene) and alpha-carotene are responsible for the orange color of carrots, and lycopene for the red color of tomatoes and astaxanthin for the red or pink color of lobsters and salmon.

The term "carotene" refers to carotenoids which contain only carbon and hydrogen (e.g. beta-carotene, alpha-carotene, lycopene), while the term "xanthophylls" refers to compounds which contain hydroxyl groups (lutein, zeaxanthin, beta-cryptoxanthin) or keto groups (canthaxanthin) or both (astaxanthin).

Major storage sites: Because the carotenoids are fat-soluble, they are found in fatty tissues in the body and are transported in blood by lipoproteins. The predominant carotenoids found in human tissues are beta-carotene, alpha-carotene, lycopene, lutein, zeaxanthin, and beta-cryptoxanthin; their relative abundance depends on dietary intake.

Functions: increased consumption of foods rich in carotenoids is associated with decreased risk of some degenerative diseases, and there is some evidence also for their role in improving immune function. In plants they serve as antioxidants to protect the highly reactive photosystems and also act as accessory photopigments.

Most recent interest has focused on antioxidant, anticancer, and immune-enhancing properties of carotenoids. Research is also continuing on food carotenoids as sources of dietary provitamin A.

Deficiency:

One study has found that carotenoid deficiency is associated with skin changes like acne and dermatitis.

Rrecommendations:

No formal diet recommendation for carotenoids has yet been established but some experts suggest intakes of 5 to 6 mg daily (about twice the average daily American intake). Individual dietary carotenoid consumption is quite variable.

Food sources:

Carotenoids are biosynthesized only in plants and some bacteria, thus foods of plant origin are the primary dietary source. Intestinal absorption can be poor, and depends on the presence of dietary fat. Mild cooking (steaming) increases bioavailability of carotenoids while overcooking can destroy some forms. The extent of conversion of provitamin A carotenoids to vitamin A seems to be variable but is less than 50%.

Toxicity:

The carotenoids are remarkably devoid of toxicity, and serve as good nontoxic sources of vitamin A. Massive overconsumption of carotenoids can result in yellowing of the skin, especially of the hand and ears (xanthosis cutis), but has no adverse health effects. The color disappears within a week or so after reducing intake of carotene-rich foods.

Sponsors