The hypothesis was that an increase in serum lycopene levels following supplementation with capsules containing natural lycopene rich tomato extract would reduce oxidative stress and improve endothelial function in healthy men with low intake of fruits and vegetables. A randomized double-blind, placebo-controlled study was designed to assess the changes in serum lycopene levels, oxidative stress and endothelial function in response to an 8-week treatment with lycopene supplementation.

The healthy men aged 20-60 years, who frequently smoked cigarettes or consumed alcohol, were enrolled in this study. Subjects were excluded if they consumed more than 3 servings/day of vegetables and fruit, or more than one serving/week of lycopene-rich foods; took antioxidant, vitamin, or mineral supplements; had any history of chronic disease; or were taking lipid-lowering or antihypertensive medications.The subjects were randomly assigned to receive placebo, 6mg, or 15mg lycopene capsule per day for 8 weeks. Study substances were suspended in soybean oil and given in acid-soluble gelatin capsules. A placebo containing soybean oil (100%) was supplied in identical-looking capsules. All the subjects were instructed to consume one capsule per day right after any meal of their choice. All participants were encouraged to maintain their usual lifestyle and dietary habits.

Inclusion Criteria:

• healthy men who frequently smoked cigarettes or consumed alcohol

Exclusion Criteria:

• consumption of more than 3 servings/day of vegetables and fruit, or more than one serving/week of lycopene-rich foods
• taking antioxidant, vitamin, or mineral supplements
• any history of chronic disease (diabetes, heart disease, renal disease)
• taking lipid-lowering or antihypertensive medications