Lycopin

Lycopene is a naturally occurring carotenoid pigment and antioxidant found in many red fruits and vegetables, most notably tomatoes. It belongs to the carotene family and is a hydrocarbon (a non-polar molecule) with 40 carbon atoms and a chain of 11 conjugated double bonds. Unlike some other carotenoids, lycopene is not a provitamin A in humans.

Natural sources and chemistry: Lycopene gives the characteristic red color to tomatoes, watermelon, pink grapefruit, papaya, guava, and certain peppers. It occurs in various cis and trans isomeric forms, with all-trans lycopene being the predominant form in raw produce but cis isomers formed during processing and digestion are more readily absorbed.

Bioavailability and metabolism: The absorption of lycopene is enhanced by dietary fat and by processing techniques such as cooking and mechanical processing, which break down plant cell walls and increase solubility. After absorption, lycopene is incorporated into chylomicrons and other lipoproteins for transport in the bloodstream.

Health effects and evidence: Lycopene acts as an antioxidant, helping to quench singlet oxygen and scavenge reactive species. Epidemiological studies have linked higher lycopene intake with reduced risk of certain conditions, notably prostate cancer and cardiovascular disease, but randomized controlled trials have yielded inconsistent results. Consequently, lycopene is not approved as a treatment for any disease, and current guidance emphasizes obtaining nutrients from a balanced diet rather than high-dose supplements.

Safety and uses: Lycopene from foods is generally regarded as safe. It can degrade with prolonged storage, light exposure, and heat, though cooking tomatoes can improve its bioavailability. In the food industry, lycopene is also used as a natural red food colorant (E160d).