Effect of 12-Week Daily Intake of the High-Lycopene Tomato (), A Variety Named "PR-7", on Lipid Metabolism: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study.

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• Lycopene, a carotenoid, has antioxidant effects and exhibits the highest physical quenching rate constant for singlet oxygen.
• Lycopene has also been reported to inhibit the production of serum lipid peroxide and oxidize low-density lipoprotein (LDL)
• This study reported that the intake of 50g of high-lycopene (lycopene, 22.0-27.8mg) for 12 weeks significantly decreased LDL-C in subjects with LDL-C ranging from 120–139 mg/dL.

A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group study was conducted to investigate the effects of the regular and continuous intake of high-lycopene tomato, a variety named PR-7, for 12 weeks on 74 healthy Japanese subjects with low-density lipoprotein cholesterol (LDL-C) levels > 120 to <160mg/dL.

The subjects were randomly assigned to either the high-lycopene tomato or placebo (lycopene-free tomato) group. Each subject in the high-lycopene group ingested 50g of semi-dried PR-7 (lycopene, 22.0-27.8mg) per day. Medical interviews were conducted, vital signs were monitored, and blood and saliva samples were taken at 0 (baseline) and at 4, 8 and 12 weeks.

Primary clinical outcomes were:

• The intake of high-lycopene tomato improved LDL-C at week 12 when compared to the placebo group (Week 12: placebo, 4,1 +- 15.7mg/dL; high-lycopene tomato, -3.7 +- 13.8.mg/dL; p=0.027).
• Based on a subgroup analysis, the ingestion of high-lycopene tomato significantly decreased LDL-C in subjects with LDL-C ranging from 120–139 mg/dL at week 12 (Week 12: placebo, 4.3   15.1 mg/dL; high-lycopene tomato, +- 5.1   9.5 mg/dL; p = 0.030).

Secondary clinical outcomes were:

• There were no significant differences between the high-lycopene tomato and placebo groups in terms of lipid profiles comprising of total cholesterol (TC), HDL-C, triglycerides (TG), LDL-C/HDL-C ratio, and non-HDL, and adiponectin.
• The intake of high-lycopene tomato increased lycopene levels compared to the placebo group (Week 12: placebo,

+-24.2 49.3 g/dL; high-lycopene tomato, 22.7 47.9 g/dL; p < 0.001).

• In addition, beta-carotene levels increased in the high-lycopene tomato group compared to those in the placebo group at week 12 (Week 12: placebo, 0.9   13.6 g/dL; high-lycopene tomato, 12.0   24.5 g/dL; p = 0.009).

• A previous meta-analysis demonstrated that LDL-C decreases when more than 25 mg per day of lycopene is ingested. The biological mechanism was associated with a reduction in 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase activity in the liver, activation of LDL-receptors, and increased expression of the ABCA1 transporter gene, the key component of HDL-C production.
• This study also suggests that there is a decrease in LDL-C at 12 weeks in subjects with LDL-C ranging from 120–139 mg/dL.
• Based on these findings, a practitioner could therefore consider recommending 25mg of lycopene to help reduce LDL-C in patients with an LDL-C range of 120–139 mg/dL for at least 12 weeks.

• Lycopene has been reported to possess the strongest singlet oxygen scavenging ability among the eight carotenoids, as measured by the singlet oxygen absorption capacity method, and some researchers have found that lycopene and tomato display antioxidant effects. However, other reports suggest that ingesting lycopene does not affect oxidative markers. These findings suggest that further investigation is needed to evaluate the effect of lycopene on oxidative markers.
• The LOX index is a biomarker for the early risk of arteriosclerosis, cerebral infarction, and myocardial infarction. Lycopene might be ineffective against LOX-1 which is a product of the peroxidation reaction. Additional studies with a longer intake period are required to investigate the effect of lycopene on the risk of arteriosclerosis.
• The subjects in this study were asked to avoid cooking the test food (semi-dried tomato). It is, therefore, necessary to investigate the differences in the effect of the high-lycopene tomato based on various cooking methods.