BMR Reference for Age 50
Basal metabolic rate at age 50 is not one number — it is a range set by height and weight. This page holds the formula inputs steady at age 50 and sweeps body composition instead: four BMI levels, men at 175 cm and women at 165 cm, each estimated with both Mifflin-St Jeor and Harris-Benedict so the spread between the classic equations is visible at a glance.
Read the BMI-25 row as a worked example: 76.6 kg at age 50 returns 1615 kcal, 5 kcal below the 49-year figure of 1620. Harris-Benedict lands 56 kcal above Mifflin (3.5%), and moving from sedentary to extra active multiplies the same estimate out to 3,069 kcal — a 1,131 kcal swing next to the 310 kcal the age term costs between 18 and 80.
BMR at age 50 by body composition
| BMI | Men (175 cm) | Women (165 cm) | ||||
|---|---|---|---|---|---|---|
| Weight | Mifflin | Harris | Weight | Mifflin | Harris | |
| 20 | 61.3 kg | 1462 kcal | 1466 kcal | 54.5 kg | 1165 kcal | 1246 kcal |
| 25 | 76.6 kg | 1615 kcal | 1671 kcal | 68.1 kg | 1301 kcal | 1372 kcal |
| 30 | 91.9 kg | 1768 kcal | 1876 kcal | 81.7 kg | 1437 kcal | 1498 kcal |
| 35 | 107.2 kg | 1921 kcal | 2080 kcal | 95.3 kg | 1573 kcal | 1624 kcal |
From BMR to daily burn: TDEE at age 50
Multiplying BMR by an activity factor gives total daily energy expenditure. The factors below are the same five levels the main calculator offers, applied to the BMI-25 man from the table (76.6 kg, BMR 1615 kcal):
| Activity level | Factor | TDEE |
|---|---|---|
| Sedentary — little or no exercise | ×1.2 | 1938 kcal/day |
| Lightly active — 1–3 days/week | ×1.375 | 2221 kcal/day |
| Moderately active — 3–5 days/week | ×1.55 | 2503 kcal/day |
| Very active — 6–7 days/week | ×1.725 | 2786 kcal/day |
| Extra active — intense daily training | ×1.9 | 3069 kcal/day |
Get your own figure
Body size matters more than any reference table can capture, so a two-minute personal estimate is usually worth more than a row of averages. Enter your numbers and the box computes the Mifflin-St Jeor result with the same coefficients used across this site:
Frequently asked questions
What is the BMR of a 50-year-old?
It depends on body size as well as age. At age 50, a 175 cm man weighing about 76.6 kg has a Mifflin-St Jeor BMR of roughly 1615 kcal per day, while a 165 cm woman at 68.1 kg lands near 1301 kcal per day. The table above shows how the estimate moves across four common body-composition levels.
Why does BMR fall as age increases?
The Mifflin-St Jeor equation subtracts 5 kcal for every year of age, so between age 20 and age 80 the estimate drops by about 300 kcal per day at the same height and weight. The coefficient is a population average: body composition, not the birthday itself, drives most of the real change.
Mifflin-St Jeor or Harris-Benedict — which should I use?
Mifflin-St Jeor is the default on this site because validation studies found it tracks measured resting energy expenditure more closely for most adults. Harris-Benedict, shown beside it in the table, runs higher for many people — often by 5 to 10 percent — so comparing the two columns is a quick way to see the uncertainty band around any single number.
Nearby ages
Want the full picture — Katch-McArdle from body-fat percentage, the age chart and TDEE in one run? Open the BMRScope calculator or browse every age page.