Carotenoids are a major topic in nutrition and health circles today. Why are they important? Because Vitamin A, long known to be crucial for normal vision, has been discovered to have a whole host of diverse biological functions. Its role in controlling the way in which cells divide, develop, and mature has become an area of much interest among scientists.

Carotenoids are converted to vitamin A mainly in the intestine and liver. About 10% of dietary carotenoids are converted to vitamin A in the body and contribute 25% of our total vitamin A. We now know that many carotenoids also have antioxidant properties and studies are underway to determine other health benefits of carotenoid metabolites besides the long-accepted role as precursors of vitamin A. Analytical data are available for five of the carotenoids found in foods and measurable in the blood. These include beta-carotene, alpha-carotene, lutein, lycopene, and beta-cryptoxanthin.

Research Findings

Eye Structure and function
Research has shown that people who consumed 3.5 or more daily servings of fruits and vegetables (in which carotenoids occur naturally) had enhanced eye health.

Immune System Enhancement
Studies suggest that carotenoids enhance immune function by a variety of mechanisms.

Heart Health
Cardiovascular health is improved by 50% in a group of men who took beta-carotene supplements every other day for five years.

Longevity
Dr. Richard Cutler from the National Institute on Aging, Gerontology Research Center, supports a significant link between lifespan and plasma carotenoid levels. He states that “Carotenoids may be biologically active not only as a protective agent, but also as a longevity determinant”.

Beta-carotene is the most well-known of the carotenoids and the predominate one in carrots, sweet potatoes, broccoli, and cantaloupe. Beta-carotene, the molecule that contains two molecules of vitamin A, plays a major role as a contributor of vitamin A in our diets. In the last few years, food scientists have been able to measure not only beta-carotene in fruits and vegetables, but also numerous other carotenoids. Today we know that provitamin A carotenoids include approximately 50 carotenoids which can be converted into at least one molecule of vitamin A. The other carotenoids (some 600 total in nature) may have important metabolic effects on the body independent of vitamin A. These as yet unidentified functions need to be considered when interpreting studies that claim health promotion properties from carotenoid-rich vegetables.

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