The average body weight of girls in Japan varies by age, with the average newborn weighing 6 pounds and 10 ounces and the average 16-year-old girl weighing 115 pounds. Japanese women between the ages of 20 and 24 weigh 110 pounds on average.
In Japan, the average 11-year-old girl weighs approximately 88 pounds and the average 14-year-old girl weighs 111 pounds. Japanese girls under the age of 10 are in the 20th percentile, while Japanese girls from the age of 10 to the late teens are in the 30th percentile, using United States percentile curves. Health experts consider one-third of women in Japan to be underweight. The Japanese are the thinnest people among citizens of developed, first-world nations.