1. Introduction
Frailty, malnutrition
OXIDATIVE STRESS, MALNUTRITION
These authors contributed equally to this work.Frailty is a huge concern for the aging population, and dietary nutrition is considered a key factor in the prevention of aging. To solve the problem of frailty in the aging population, we developed a novel dietary intervention program using a novel COMpletely Balanced for Frailty Prevention (COMB-FP) meal, based on the Dietary Reference Intake for Japanese; in addition, we conducted a pilot randomized control trial comparing an exercise program only (control group) with exercise plus the COMB-FP meal program (test group). We included 110 male and female healthy volunteers with pre-frailty or frailty; the trial lasted for 12 weeks. Two daily meals were replaced with the COMB-FP meals during the trial in the test group. Walking speed and cognitive function were significantly improved in the test group compared with the control group. We observed a similar pattern in other frailty-related outcomes, such as occupancy of the microbiome, World Health Organization well-being index (WHO-5), and oxidative stress. Our study might indicate the importance of a well-balanced intake of nutrients for frailty prevention.With the aging population worldwide, especially in developed countries, there is a corresponding increase in the prevalence of age-related conditions, and frailty is one of the important associated issues [The association of dietary nutrition intake with frailty is also well studied, and malnutrition is considered one of the key factors in frailty [Thus, dietary intervention, and not intervention with supplements of only a few nutrients, might be a reasonable treatment for frailty. A popular dietary intervention for frailty is the “Nu-age study”, a large-scale RCT involving thousands of participants. Participants in the intervention group were well educated on the essentials of the Mediterranean diet (a guideline consisting of 14 kinds of foods, such as whole grains, vegetables, meat, nuts, oil, alcohol, sweets, and others) and received vitamin D supplements [We previously reported on a novel dietary intervention program using the COMpletely Balanced meal (“COMB meal”), which included 33 kinds of nutrients, basically referring to guidelines in Japan [