Effect of diet and smoking on serum lycopene and lipid peroxidation

Lycopene, a naturally present carotenoid in tomatoes and other fruits, has been proposed to have antioxidant and potential anticarcinogenic properties in recent studies. This study was conducted to investigate the effect of diet and smoking on serum lycopene and lipid peroxidation expressed as thiobarbituric acid reactive substances (TBARS) in 20 healthy human subjects. A reduction of 50% in the serum lycopene levels and an increase of 25% in TEARS was observed when subjects were maintained on a lycopene-free diet. Serum lycopene levels were also reduced by 25% following a meal compared to the fasting levels. Serum lycopene levels of habitual smokers were compared with non-smokers. Although the levels were not significantly different between the two groups, serum lycopene levels fell by 40% with a 40% increase in TEARS in smokers following smoking three cigarette. This study showed that the levels of serum lycopene were influenced significantly as a result of oxidative stress in the form of diet induced metabolism and smoking, suggesting in vivo antioxidant properties of lycopene. (C) 1998 Elsevier Science Inc.