As healthy lifestyles become increasingly popular, more people are working to overcome their unbalanced diets and lack of exercise. As part of its commitment to offering new value, Suntory has consistently been at the forefront of this trend with innovative products and services. Our research on commercial materials has yielded important insights about various polyphenols, including wine polyphenols, sesamin in sesame, and polymerized polyphenols in oolong tea. One of our research priorities has been exploring the function of quercetin, a compound included in onions, broccoli, apples, and green tea.
The prevention and reduction of obesity is a critical social issue that we must address. The 2012 National Health and Nutrition Survey by the Ministry of Health, Labour and Welfare revealed that 29.1% of Japanese men and 19.4% of Japanese women are overweight, which was defined as having a body mass index (BMI) of 25kg/m² and more. Abdominal obesity in particular greatly increases the risk of fatal diseases such as arteriosclerosis, heart disease, and stroke—particularly if the person concurrently suffers from two or more of the following: hyperglycemia, hypertension, lipid disorder.
In response to this challenge, Suntory has been actively researching and developing food for specified health uses, or FOSHU products, to help combat obesity and improve the health of society as a whole.
* Body mass index (BMI) is a measure of body fat based on weight and height. "Underweight" is generally defined as less than 18.5kg/m², "normal” (healthy weight) as 18.5kg/m² to 25kg/m², "overweight" as 25kg/m² to 30kg/m², and "obese" as 30kg/m² or more.
Quercetin is a kind of polyphenol that is abundant in common vegetables like onions and broccoli. Physiologically, it can act as an antioxidant and anti-inflammatory, or even combat high blood pressure. Though previous studies have shown that quercetin can help lipolysis and decrease cholesterol level, there were no reports on anti-obesity effect.
Further, quercetin is not highly soluble, and has the characteristic of not being absorbed in the body easily. However, it has become clear that when quercetin is combined with sugar to form quercetin glucoside, the solubility increases and, in the small intestine, the glucoside is hydrolyzed to quercetin, which is absorbed into the body more easily.
We therefore decided to examine the effects on body fat reduction, using quercetin glucoside.
We then conducted experiments on body fat reduction in people who consumed soft drinks containing quercetin glucoside.
The experiment involved 200 subjects age 20–65 with a BMI between 24 and 31kg/m². One group was given a beverage containing quercetin glucoside and the other a beverage without it. The beverages both looked and tasted the same, and the subjects did not know which one they were drinking. After they drank the beverages once a day for 12 weeks, we used a CT scan to measure abdominal fat. We found that abdominal fat measurements in the quercetin glucoside group decreased significantly over the twelve weeks and in comparison to the control group, confirming the effects of quercetin glucoside on the reduction of body fat.
Having confirmed the ability of quercetin glucoside to reduce body fat, Suntory set out to develop a FOSHU beverage for overweight consumers looking to get healthier. We sent the findings of our fat reduction experiment as well as various safety trials to the Consumer Affairs Agency, which approved our FOSHU application. Suntory will continue its research on the health effects of polyphenols and other food ingredients with the aim of further contributing to consumer health.