The human body has always been a wonder.
Data from the National Center for Health Statistics (NCHS), published in June 2025, has revealed how height, weight, and waistlines change with age across the American population.
TL;DR
- Between the ages of 2 and 3, girls and boys weigh an average of 15 kg and 14.5 kg, respectively.
- The most significant jumps occur during puberty, after which growth levels off.
- Men in their 20s typically measure 175-178 cm, while women average 162-164 cm.
- Height gradually declines in older years due to aging factors.
Body measurements were obtained from 8,545 participants in the United States aged 2 years and older. Measurements included weight, height, circumferences, and limb lengths.
By the ages of 14-15, the average weight for boys (“16-17”) climbs dramatically, often more than doubling or tripling earlier childhood weights.
Girls similarly gain more, but with a slightly different trajectory, particularly during puberty.
Comparing the Average Human Body Measurements by Age
Below, we show the mean weight and height of the average human body by age:
| wdt_ID | wdt_created_by | wdt_created_at | wdt_last_edited_by | wdt_last_edited_at | Age group | Mean weight (kg): Male | Mean weight (kg): Female | Mean height (cm): Male | Mean height (cm): Female |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Monica Ebunoluwa | 10/06/2026 02:05 PM | Monica Ebunoluwa | 10/06/2026 02:05 PM | 2–3 years | 15.0 | 14.5 | 95.2 | 94.4 |
| 2 | Monica Ebunoluwa | 10/06/2026 02:05 PM | Monica Ebunoluwa | 10/06/2026 02:05 PM | 4–5 years | 20.3 | 19.5 | 110.2 | 108.9 |
| 3 | Monica Ebunoluwa | 10/06/2026 02:05 PM | Monica Ebunoluwa | 10/06/2026 02:05 PM | 6–7 years | 25.5 | 26.0 | 122.6 | 122.7 |
| 4 | Monica Ebunoluwa | 10/06/2026 02:05 PM | Monica Ebunoluwa | 10/06/2026 02:05 PM | 8–9 years | 33.5 | 34.3 | 134.6 | 134.8 |
| 5 | Monica Ebunoluwa | 10/06/2026 02:05 PM | Monica Ebunoluwa | 10/06/2026 02:05 PM | 10–11 years | 46.7 | 46.0 | 146.8 | 148.7 |
| 6 | Monica Ebunoluwa | 10/06/2026 02:05 PM | Monica Ebunoluwa | 10/06/2026 02:05 PM | 12–13 years | 58.3 | 55.4 | 162.0 | 156.4 |
| 7 | Monica Ebunoluwa | 10/06/2026 02:05 PM | Monica Ebunoluwa | 10/06/2026 02:05 PM | 14–15 years | 71.2 | 61.9 | 171.1 | 159.6 |
| 8 | Monica Ebunoluwa | 10/06/2026 02:05 PM | Monica Ebunoluwa | 10/06/2026 02:05 PM | 16–17 years | 76.3 | 64.4 | 175.0 | 161.5 |
| 9 | Monica Ebunoluwa | 10/06/2026 02:05 PM | Monica Ebunoluwa | 10/06/2026 02:05 PM | 18–19 years | 77.0 | 69.1 | 175.1 | 161.5 |
| 10 | Monica Ebunoluwa | 10/06/2026 02:05 PM | Monica Ebunoluwa | 10/06/2026 02:05 PM | 20–29 years | 86.8 | 77.9 | 176.3 | 163.5 |
Notable Mid-Life Trends in Adults
The mean weight for males aged 20-29 is about 86-90 kg, rising slightly in the 30s and 40s, then tending to plateau or even drop in older age groups.
For women, the mean weight in the 20s is roughly 74-78 kg, with slow, gradual increases through middle age, followed by modest declines in late age (80+).
Height in adulthood shows similarly modest changes with age. Men in their 20s typically average 175-178 cm, while women average around 162-164 cm.
By the time people reach their 70s or older, slight decreases begin to appear. According to the survey, this is partly due to spinal compression, changes in posture, and general aging.
Body Mass Index
The report also highlights the average Body Mass Index (BMI), waist and hip circumferences, and limb measurements (upper arm and upper leg), all of which help flesh out growth trends and health risks.
Children’s BMI remains lower but increases through adolescence, with percentiles showing widening variation.
In adults, BMI reflects a broader spread. High percentiles show greater weight relative to height, correlating with increased prevalence of overweight and obesity concerns.
ELI5
Between the ages of 2 and 3, girls and boys weigh an average of 15 kg and 14.5 kg, respectively. The most significant jumps occur during puberty, after which growth levels off. Men in their 20s typically measure 175-178 cm, while women average 162-164 cm.
Source:
National Center for Health Statistics | U.S. Centers for Disease Control and Prevention