Dietary Intake of Carotenoid-Rich Vegetables Reduces Visceral Adiposity in Obese Japanese men-A Randomized, Double-Blind Trial.

Tomohisa Takagi,Mayuko Morita,Yoichi Mihara,Yuji Naito,Kazuhiko Uchiyama,Yoshito Itoh,Shinji Okada,Yuji Nakai,Katsura Mizushima,Ryotaro Hayashi,Mayumi Yamada,Rumiko Miyashita

doi:10.3390/nu12082342

Abstract

Metabolic syndrome, whose main diagnostic component is obesity, is a risk factor for lifestyle-related diseases, type 2 diabetes, and cardiovascular disease. Diet is known to affect the prevalence of metabolic syndrome. However, the effect of diet on metabolic syndrome in Japanese subjects has not been thoroughly explored. In the present study, we investigated the effect of carotenoid-rich vegetables, particularly lycopene- and lutein-rich vegetables, on the metabolic syndrome in obese Japanese men. We conducted an 8-week long randomized, double-blinded, controlled clinical trial in which, 28 middle-aged (40 ≤ age < 65) Japanese men with high body mass index (BMI ≥ 25) were randomized into four dietary groups: high lycopene + high lutein (HLyHLu), high lycopene + low lutein (HLyLLu), low lycopene + high lutein (LLyHLu), and low lycopene + low lutein (LLyLLu). Our results showed that daily beverage-intake increased the plasma levels of carotenoids without adverse effects, and the visceral fat level was significantly decreased in all the groups. The waist circumference was significantly decreased only in the HLyLLu group, whereas the CoQ10 oxidation rate was decreased in all the groups. The gene expression profiles of whole blood samples before and after ingestion differed only in the LLyLLu group, indicating the effect of carotenoids on gene expression profile. In conclusion, our results suggest that dietary uptake of carotenoid-rich vegetables increases their concentration in blood and reduces the intra-abdominal visceral fat.

Highlights

One of the main diagnostic components of metabolic syndrome is obesity, which is usually measured by the waist circumference and the intra-abdominal visceral fat, in addition to dyslipidemia (the condition of raised triglycerides and reduced high density lipoprotein (HDL)-cholesterol in blood); other components are raised blood pressure and fasting plasma glucose, all of which are related to weight gain
(LLyLLu group), 2 men were excluded from the analysis, one because the received serum sample was inadequate and the other because of pharmacological treatment commencement for a non-related with this study issue
The 8 week-ingestion offunctionality carotenoids may be of indicative of the vegetables with high carotenoid-content and their inhibited the oxidative stress status, as this was revealed by the inhibition of % coenzyme Q10 (CoQ10). These results may be indicative of the usefulness of vegetables with high carotenoid-content and their functionality on the health of individuals that have a high risk for developing metabolic syndrome, this study only considered obese middle-aged Japanese men

Summary

Introduction

One of the main diagnostic components of metabolic syndrome is obesity, which is usually measured by the waist circumference and the intra-abdominal visceral fat, in addition to dyslipidemia (the condition of raised triglycerides and reduced high density lipoprotein (HDL)-cholesterol in blood); other components are raised blood pressure and fasting plasma glucose, all of which are related to weight gain. 30.4% in males and 21.1% in females [1], and the metabolic syndrome has been linked to an increased risk of type 2 diabetes and cardiovascular disease [2]; the promotion of the appropriate body weight management has been an important issue for the national health program. Both positive and negative relationships between metabolic syndrome and diet have been reported; on the one hand, it was shown that the Mediterranean diet reduced the prevalence of metabolic syndrome and the associated cardiovascular risk by reducing the systemic vascular inflammation and endothelial dysfunction [3]. Diet affects the prevalence of metabolic syndrome [4].

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Results

Conclusion