The appeal of a deeply orange carrot does not stop at the eyes. Foods that are high in beta carotene are now being linked to lowered levels of cancer, as well as reduced risks for heart disease. Fruits and vegetables with a rich yellow or orange color are most likely to be high in this substance. The following article will give an overview of this eye-protecting, heart-happy substance. It will also include some interesting information on emerging clinical studies that show promising results in regard to the many benefits of this healing vitamin precursor for the body.
What is Beta Carotene?
Beta-carotene, the most common form of carotene, is an important organic compound derived in abundance from fruits and vegetables. There are ten types of carotenes that are synthesized by plants, but alpha and beta carotene are the only types that the human body can use as a precursor to Vitamin A. And within the hundreds of types of carotenoids created by plants, only 10% give us the important provitamin form of vitamin A carotenoid.
Beta carotene is further typified as a terpenoid, a kind of red to yellowish-orange pigment required for the production of vitamin A (retinol) in the body. In order for us to have healthy eyes, skin, and an optimally functioning heart, the body needs Vitamin A, and the beta-carotene that supports its productions. What is more, beta-carotene is another form of anti-inflammatory and free-radical-fighting antioxidant. It is from these antioxidant capacities that beta carotene aids in stopping harmful cancerous tumor growth.
Mechanisms of Action in Beta Carotene
Beta carotene is a fat-soluble (lipophilic) hydrocarbon that is naturally synthesized by plants. It is converted into retinol in the human body. Beta carotene may act to inhibit changes cellular modulation and cell cycle regulatory proteins, alterations in insulin-like growth factor-1. These processes stop a cell from changing into a cancerous growth by preventing the process of oxidative DNA damage. What is more, this hydrocarbon antioxidant can induce glutathione production in our cells, a process which also increases antioxidant activity. Beta carotene may also increase the amount and functioning of cancer-fighting enzymes in the cells. Beta carotene also stimulates increased levels of T-helper lymphocytes, (NK) cell cytotoxicity (a natural form of cancer-killing cells), as well as macrophage action.
Health Benefits of Beta Carotene
The health benefits of this vitamin A precursor are numerous. The following highlights some of the most important and effective benefits that the antioxidant may provide:
Foods That Are High in Beta Carotene
Many fruits and vegetables contain beta carotene, but the highest foods are those that have the distinctive yellow or orange color. These include carrots, mangoes, pumpkin, sweet potato, apricots, papayas, winter squash, and cantaloupe. Crude palm oil and the Vietnamese gac fruit have the highest amounts of beta carotene. And while these foods are not readily available, the amounts of beta carotene in these substances is over ten times that of a common carrot. There are also other foods that are not yellow or orange, and yet still act as excellent sources. These include most leafy greens such as kale, chard, collard greens, greener types of lettuce, sweet potato leaves, sweet gourd leaves, arugula, as well as broccoli. Interestingly enough, beta carotene is actually more bioavailable for the human when fruits and vegetables are cooked, finely chopped or pureed.
Meta-analysis studies found that serum beta-carotene could reduce the incidence of cataract formation in the eyes.
Similar studies found that long-term beta-carotene supplementation could increase cognitive function in the mind.
Supplement Information and Side Effects of Consumption
Because beta carotene is not technically an essential nutrient, there are no recommended dosages. Most of the needed amounts can be found easily in a diet high in fruit and vegetable content. This equates to approximately five-six milligrams or 8,000 to 10,000 IUs of beta-carotene per day. Always consult your doctor before taking any supplement. Very high amounts of beta-carotene can cause cartotenodermia, a condition of the yellowing of the skin, particularly on the soles of feet and palms of the hand. Individuals who smoke should also avoid supplementing with beta carotene.
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