Alpha-carotene is a provitamin A carotenoid present in fruits and vegetables. Higher serum concentrations of α-carotene have been associated with lower risk of cancer and all-cause mortality. It was suggested that genetic variants influence serum concentrations of provitamin A. Recently was found, that α-carotene effectively inhibits Lewis lung carcinoma (LLC) metastasis and suppresses lung metastasis in combination with taxol in LLC-bearing mice, suggesting that Alpha-carotene could be used as an anti-metastatic agent or as an adjuvant for anti-cancer drugs.

Beta-carotene is found in many foods and is sold as a dietary supplement. Beta-carotene is a carotenoid, weak antioxidant; precursor of vitamin A, which is essential for vision and growth. Used to reduce the severity of photosensitivity reactions in patients with erythropoietic protoporphyria (EPP). Has been used in high-dose antioxidant supplements containing ascorbic acid and vitamin E with zinc in high-risk patients with age-related macular degeneration. Beta-carotene is also used to decrease asthma symptoms caused by exercise; to prevent certain cancers, heart disease, cataracts; and to treat AIDS, alcoholism, Alzheimer’s disease, depression, epilepsy, headache, heartburn, high blood pressure, infertility, Parkinson’s disease, rheumatoid arthritis, schizophrenia, and skin disorders including psoriasis and vitiligo.

Lycopene is the fat-soluble pigment that gives tomatoes, watermelon, pink grapefruit, and other foods their red color. Bioavailability of lycopene is enhanced in the presence of lipids and thermal processing. Lycopene accounts for about 50% of the carotenoids found in human serum and is among the major carotenoids present in human milk. The antioxidant activity of lycopene and its use in cancer prevention and cardiovascular disease have been widely documented. The scientific literature documents some adverse reactions, such as diarrhea, dyspepsia, gas, nausea, and vomiting. One trial documented a cancer-related hemorrhage in a patient taking lycopene, although causality is unclear. Lycopene interacts with some cancer chemotherapy agents, as well as with ciprofloxacin and olestra.