Status of Normal Weight Obesity Among Japanese Women Under 40 Years Old

Abstract

This study examined the prevalence of and factors affecting normal weight obesity (NWO) among women aged under 40 years old. NWO was having a normal BMI but a high body-fat percentage (BFP). Materials and Methods: We recruited 399 participants aged 1839 during a health checkup and surveyed them about lifestyle patterns, height, weight, body composition, and girth and visceral fat area. Participants were divided into three. Those with a BMI of < 25 and a BFP of < 30 were classified as non-obese, a BMI of < 25 and a BFP of ≥30 as NWO, a BMI of ≥25 and a BFP of ≥30 as obese. The analysis was conducted on NWO (97) and non-obese (262) groups. Results: NWO prevalence ranged from 20% to 30% across the three age groups. NWO participants had lower values for segmental lean body mass, particularly in lower limb, and higher values for abdominal girth and visceral fat area. Among participants aged 3039, those with NWO had higher values for triglycerides and LDL cholesterol and lower values for HDL cholesterol. Regarding lifestyle factors, among those aged 3039, NWO was associated with past weight fluctuation, respectively. In the latter age group, a gain of more than 10 kg since the age of 20 was associated with a 13-fold increase in the odds for NWO. Conclusions: Results suggest that for women under 40 years, detecting NWO early and guidance on effective lifestyle and exercise are necessary.

An association between the physical activity level and skeletal muscle mass index in female university students with a past exercise habituation

“…Thus, it is suggested that the decrease in muscle mass, associated with the problems of body composition, is observed earlier in the lower limbs than in the upper limbs. Previous studies also reported that gait speed was significantly positively correlated with SMI among young women [ 10 ], and it was a predictor of NWO among participants aged 20–29 [ 28 ]. Therefore, the current PAL among female students especially affects the lower limb muscle mass, and it may cause difficulty in independent mobility in the younger generation, even in those who had an exercise habituation in the past.…”

“…Furthermore, normal weight obesity (NWO), which means that the body weight is normal; however, the body fat is high, which is considered an issue of body composition. NWO individuals were associated with a significantly lower AMM when compared with non-obese individuals in their thirties [ 28 ]. However, such a significantly lower AMM in individuals with NWO in their twenties and aged 18–19 years was observed only in the lower limbs [ 28 ].…”

“…NWO individuals were associated with a significantly lower AMM when compared with non-obese individuals in their thirties [ 28 ]. However, such a significantly lower AMM in individuals with NWO in their twenties and aged 18–19 years was observed only in the lower limbs [ 28 ]. Thus, it is suggested that the decrease in muscle mass, associated with the problems of body composition, is observed earlier in the lower limbs than in the upper limbs.…”

The Relationship between Locomotive Syndrome Risk, Gait Pattern, and Standing Posture in Young Japanese Women: A Cross-Sectional Study

“…Therefore, stabilizing the standing posture and preventing impaired walking function lead to preventive care [ 6 , 7 ]. However, young women have problems with “thinness” accompanied by muscle loss and atrophy, and “hidden obesity” with normal BMI and low lean mass [ 8 , 9 ]. The presence of muscle atrophy (sarcopenia) has been reported in women in their 20s.…”

Association between nutritional intake status and appendicular muscle mass in female university students with a high physical activity level

“…These results suggest that a high PAL as well as total energy intake and protein intake among the three macronutrients are contributed with high muscle mass and muscle strength in young females. こと (Hayashi et al, 2006;Sugawara et al, 2009)や正常体重肥満など身体組成に関する 問題 (Fukuoka et al, 2012;Nakanishi et al, 2020)…”