Lycopene is a carotenoid, and is present in human serum, liver, adrenal glands, lungs, prostate, colon, and skin at higher levels than other carotenoids. Lycopene has been found to possess antioxidant and antiproliferative properties in animal and in vitro studies, although activity in humans remains controversial.

Numerous epidemiological investigations have correlated high intake of lycopene-containing foods or high lycopene serum levels with reduced incidence of cancer, cardiovascular disease, and macular degeneration. However, estimates of lycopene consumption have been based on reported tomato intake, not on the use of lycopene supplements. Since tomatoes are sources of other nutrients including vitamin C, folate, and potassium, it is not clear that lycopene itself is beneficial.

There is no established definition of "lycopene deficiency," and no direct evidence that repletion of low lycopene levels has any benefit.

ψ, ψ-carotene, all-trans lycopene, Lycopersicon, Lycopersicon esculentum, solanorubin, tomato.

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Age-related macular degeneration prevention (Grade: C)
Based on antioxidant properties observed in laboratory studies, lycopene has been suggested as a preventive therapy for age-related macular degeneration. Preliminary human studies have overall not found a clear benefit. More research is needed before a recommendation can be made.

Antioxidant (Grade: C)
Laboratory research suggests that lycopene, like other carotenoids, may have antioxidant properties. However, it is not clear if lycopene has these effects in the human body. Results of different studies do not agree with each other, and better research is needed before a firm conclusion can be drawn.

Asthma caused by exercise (Grade: C)
Laboratory research suggests that lycopene, like other carotenoids, may have antioxidant properties. It has been suggested that antioxidants may be helpful in the prevention of asthma that is caused by exercise. There is limited, poor-quality research in this area, and further evidence is needed before a recommendation can be made.

Atherosclerosis ("clogged" arteries) and high cholesterol (Grade: C)
It has been suggested that lycopene may be helpful in people with atherosclerosis or high cholesterol, possibly due to antioxidant properties. Several studies have been published in this area, most using tomato juice as a treatment. Results have not agreed with each other, and this issue remains unclear.

Breast cancer prevention (Grade: C)
Research in animals and observations of large human populations have examined the relationship between developing breast cancer and tomato intake or lycopene levels in the body. The evidence in this area is not clear, and further studies are needed before a firm conclusion can be drawn.

Cancer prevention (general) (Grade: C)
Studies have examined large populations to identify which lifestyle factors affect health. Many of these "epidemiologic" or "population" studies suggest a link between diets high in fruits and vegetables and a decreased risk of developing cancer. However, it is not entirely clear which foods are most beneficial, or if reduced cancer is due to other (non-dietary) aspects of a "healthy lifestyle."

Cervical cancer prevention (Grade: C)
Observations of large human populations suggest possible benefits of tomato product intake in preventing cervical cancer. However, other studies report no benefits. Research that specifically studies lycopene supplements is lacking.

Gastrointestinal tract and colorectal cancer prevention (Grade: C)
Multiple studies have examined whether intake of tomatoes or tomato-based products helps prevent digestive tract cancers, including oral, pharyngeal, esophageal, gastric, colon, and rectal. Results have been inconsistent, with some studies reporting significant benefits, and others finding no effects. Research that specifically studies lycopene supplements is limited, and more research is needed in this area before a conclusion can be drawn.

High blood pressure associated with pregnancy (pre-eclampsia) (Grade: C)
Based on early study, lycopene may reduce the development of pre-eclampsia and intrauterine growth retardation in women having their first child. Further research is needed to confirm these results.

Infertility (Grade: C)
Based on early study, taking lycopene seems to have a role in the management of idiopathic male infertility. Further research is needed to confirm these results.

Lung cancer prevention (Grade: C)
Several studies observing large populations report a lower risk of developing lung cancer in people who regularly eat tomatoes. However, other studies report no benefits of tomato consumption. Research that specifically studies lycopene supplements is lacking.

Prostate cancer prevention (Grade: C)
Studies of large populations report mixed results as to whether eating tomatoes/tomato-based products reduces the risk of developing prostate cancer. Research that specifically studies lycopene supplements is lacking.

Sun protection (Grade: C)
Lycopene in combination with other carotenoids such as beta-carotene, vitamins C an E, selenium and proanthocyanidins, may help in reducing sunburn.

Immune stimulation (Grade: D)
It has been proposed that lycopene and other carotenoids, such as beta-carotene, may stimulate the immune system. However, several studies of lycopene supplements and tomato juice intake in humans report no effects on the immune system.

Lung function after exercise (Grade: D)
A daily dose of lycopene for one week does not seem to affect lung function after exercise and does not provide any protective effect against clinical difficulty in breathing in young athletes.