Chlorella is rich in beta-carotene, which is known to:

• Protect your cells from the damaging effects of free radicals
• Provide a source of vitamin A
• Enhance the functioning of your immune system
• Help your reproductive system function properly

What events and lifestyle factors can indicate a need for more foods that are rich in beta-carotene?

• Low intake of fruits and vegetables
• Smoking and regular alcohol consumption

Unlike supplements, foods rich in beta-carotene pose no lung cancer risk. Synthetic beta-carotene supplements have been found to increase the risk of both colorectal and lung cancer in smokers, especially those who also drink alcohol. A study published by an international team in the January 2004 issue of Cancer Epidemiology Biomarkers and Prevention indicates that beta-carotene consumed as part of whole foods has no such negative effects. This study, which pooled data from seven large cohort studies running between 7 and 16 years and involving a subject population of 399,765 participants in North America and Europe, found that beta-carotene from foods was not associated with any increased risk of lung cancer among current smokers or non-smokers. Other carotenoids in foods (lutein, zeaxanthin and lycopene) were also found to have no association with lung cancer risk. (February 26, 2004)

Food sources of beta-carotene include sweet potatoes, carrots, kale, spinach, turnip greens, winter squash, collard greens, cilantro and fresh thyme. To maximize the availability of the carotenoids in the foods listed above, the foods should be eaten raw or steamed lightly.

What is beta-carotene?

Beta-carotene is probably the most well known of the carotenoids, a phytonutrients family that represents of the one most widespread groups of naturally occurring pigments.

While beta-carotene produces colors in the orange and yellow range, beta-carotene rich foods may be other colors besides from these two. That is because other phytonutrients pigments blend together with the beta-carotene to give the plant food its unique hue that, in addition to orange or yellow, could be other colors including pink, red or white.

Preventing Vitamin A Deficiency

Until late in the 20th Century, the functions of carotenoids, including beta-carotene, were discussed only in terms of their potential vitamin A activity. Beta-carotene is one of approximately 50 carotenoids of the known 600, that are called "provitamin A" compounds because the body can convert them into retinol, an active form of vitamin A.
As a result, foods that contain beta-carotene can help prevent vitamin A deficiency.

Antioxidant & Immune-Enhancing Activity

In recent years, carotenoids including beta-carotene have received a tremendous amount of attention as potential anti-cancer and anti-aging compounds. Beta-carotene is a powerful antioxidant, protecting the cells of the body from damage caused by free radicals. It is also one of the carotenoids believed to enhance the function of the immune system.

Promoting Proper Cell Communication

In addition to their antioxidant and immune-enhancing activity, carotenoids including beta-carotene have shown the ability to stimulate cell to cell communication. Researchers now believe that poor communication between cells may be one of the causes of the overgrowth of cells, a condition which eventually leads to cancer. By promoting proper communication between cells, carotenoids may play a role in cancer prevention.

Supporting Reproductive Health

It is also believed that beta-carotene may participate in female reproduction. Although its exact function in female reproduction has not yet been identified, it is known that the corpus luteum has the highest concentration of beta-carotene of any organ in the body, suggesting that this nutrient plays an important role in reproductive processes.

Deficiency Symptoms

A low dietary intake of carotenoids such as beta-carotene is not known to directly cause any diseases or health conditions, at least in the short term. However, if your intake of vitamin A is also low, a dietary deficiency of beta-carotene and/or other provitamin A carotenoids can cause the symptoms associated with vitamin A deficiency.

In addition, long-term inadequate intake of carotenoids is associated with chronic disease, including heart disease and various cancers. One important mechanism for this carotenoid-disease relationship appears to be free radicals. Research indicates that diets low in beta-carotene and carotenoids can increase the body's susceptibility to damage from free radicals. As a result, over the long term, beta-carotene deficient diets may increase tissue damage from free radical activity, and increase risk of chronic diseases like heart disease and cancers.

Health Conditions

Carotenoids may play a role in the prevention of the following health conditions:

• Acquired Immunodeficiency Syndrome (AIDS)
• Age-related macular degeneration
• Angina pectoris
• Asthma
• Cataracts
• Cervical cancer
• Cervical dysplasia
• Chlamydial infection
• Heart disease
• Laryngeal cancer (cancer of the larynx)
• Lung cancer
• Male and female infertility
• Osteoarthritis
• Photosensitivity
• Pneumonia
• Prostate cancer
• Rheumatoid arthritis
• Skin cancer
• Vaginal candidiasis

Food Sources

Beta-carotene can be found in concentrated amounts in a variety of foods including sweet potatoes, carrots, kale, spinach, turnip greens, winter squash, collard greens, cilantro, fresh thyme, cantaloupe, romaine lettuce and broccoli. As the table below shows, Chlorella is an excellent, concentrated natural food source of Beta-carotene.

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