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

Mie Nishimura,Jun Nishihira,Naoki Tominaga,Yuko Ishikawa-Takano,Mari Maeda-Yamamoto

doi:10.3390/nu11051177

Abstract

Tomato (Solanum lycopersicum) is a rich source of lycopene, a carotenoid that confers various positive biological effects such as improved lipid metabolism. Here, we conducted a randomized, double-blind, placebo-controlled, parallel-group comparative study to investigate the effects of regular and continuous intake of a new high-lycopene tomato, a variety named PR-7, for 12 weeks, based on 74 healthy Japanese subjects with low-density lipoprotein cholesterol (LDL-C) levels ≥120 to <160 mg/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 50 g of semidried PR-7 (lycopene, 22.0–27.8 mg/day) each day for 12 weeks, while subjects in the placebo group ingested placebo semidried tomato. Medical interviews were conducted, vital signs were monitored, body composition was determined, and blood and saliva samples were taken at weeks 0 (baseline), 4, 8, and 12. The primary outcome assessed was LDL-C. The intake of high-lycopene tomato increased lycopene levels in this group compared to levels in the placebo group (p < 0.001). In addition, high-lycopene tomato intake improved LDL-C (p = 0.027). The intake of high-lycopene tomato, PR-7, reduced LDL-C and was confirmed to be safe.

Highlights

Dyslipidemia is a major risk factor for coronary heart disease, and in Japan, the number of patients with this condition is increasing
We opted to produce semidried tomato and used lycopene-free tomato as the placebo. By using this test food in a double-blind, placebo-controlled study, we demonstrated that semidried tomato is similar to raw tomato and its lycopene-induced effect is the same as that of processed tomato such as juice or extract
We assessed the effect of daily intake of high-lycopene tomato for 12 weeks on lipid profiles in Japanese subjects with low-density lipoprotein cholesterol (LDL-C) levels ≥120 mg/dL and

Summary

Introduction

Dyslipidemia is a major risk factor for coronary heart disease, and in Japan, the number of patients with this condition is increasing. The Ministry of Health, Labor and Welfare reported that 2.1 million patients received treatment for this condition in 2014. It is well known that dietary improvements are important for the prevention of dyslipidemia, and research on functional foods that affect lipid metabolism is receiving increased attention. As this system permits health claims for fresh vegetables, the research on and development of such vegetables containing highly functional components, known as “functional vegetables”, is expected. It has been reported to inhibit the production of serum lipid peroxide and oxidize low-density lipoprotein (LDL) in a concentration-dependent manner [2]

Methods

Results

Conclusion