Lycopene bent rather than linear shape. Different isomers were shown to have different stabilities due to their molecular energy (highest stability: 5-cis ≥ all-trans ≥ 9-cis ≥ 13-cis > 15-cis > 7-cis > 11-cis: lowest). In human blood, various "cis"-isomers constitute more than 60% of the total lycopene concentration, but the biological effects of individual isomers have not been investigated. Carotenoids like lycopene are found in photosynthetic pigment-protein complexes in plants, photosynthetic bacteria, fungi, and algae. They are responsible for the bright orange–red colors of fruits and vegetables, perform various functions in photosynthesis, and protect photosynthetic organisms from excessive light damage.
Lycopene pressure, interactions with drugs that affect blood pressure may occur. Lycopene may affect the immune system, the nervous system, sensitivity to sunlight, or drugs used for stomach ailments. Lycopenemia is an orange discoloration of the skin that is observed with high intakes of lycopene. The discoloration is expected to fade after discontinuing excessive lycopene intake. In a review of literature on lycopene and its potential role as a dietary antioxidant, the European Food Safety Authority concluded that evidence was insufficient for lycopene having antioxidant effects in humans, particularly in skin, heart function, or vision protection from ultraviolet light. Although lycopene