Calorie needs at age 38, female
Enter your age, size and activity to see how many calories you use each day. The example below is a woman aged 38 who is 5 ft 4 in tall and weighs 150 lb.
How it works
Daily calories equal resting calories times an activity factor. Resting calories come from Mifflin-St Jeor: 10 times kilograms plus 6.25 times centimeters minus 5 times age, with 5 added for males or 161 taken off for females. The factor runs from 1.2 to 1.9. For a woman aged 38 at the lightly active level the age term takes 190 calories off.
Worked example
Say a woman aged 38 is 5 ft 4 in tall and weighs 150 lb. That is 162.56 cm and 68.04 kg. The weight term is 10 × 68.04 = 680.4. The height term is 6.25 × 162.56 = 1016. The age term is 5 × 38 = 190. Subtract 161. The result is 1345.4 at rest. Times 1.375 for the lightly active level is 1849.9, which rounds to 1850 calories a day.
Maintenance calories at every activity level for the same woman aged 38 at 5 ft 4 in and 150 lb, with the lightly active level set in the form above.
- Sedentary (little or no exercise)
- 1614 calories a day
- Lightly active (light exercise 1 to 3 days a week)
- 1850 calories a day
- Moderately active (moderate exercise 3 to 5 days a week)
- 2085 calories a day
- Very active (hard exercise 6 to 7 days a week)
- 2321 calories a day
- Extra active (very hard exercise and a physical job)
- 2556 calories a day
Common questions
How big a calorie deficit is reasonable for weight loss?
A deficit of 500 calories a day is a common starting point and works out to roughly half a kilogram a week. Smaller deficits are slower and easier to keep up. A 500 calorie deficit here means 1350 calories a day for this 38-year-old woman at the lightly active level.
How big a surplus helps build muscle?
A modest surplus of about 250 calories a day is a common starting point. Larger surpluses tend to add more fat without adding muscle faster. A 250 calorie surplus here means 2100 calories a day for this 38-year-old woman at the lightly active level.
Why does age 38 change the result?
The formula takes 5 calories off for every year of age, which reflects that resting burn tends to fall over time. At 38 that is 190 calories. Without the age term this 38-year-old woman would burn 1535 calories at rest, or 2111 a day at the lightly active level.
How accurate is a calorie estimate?
It is a starting estimate. Track your weight over two or three weeks and adjust the target up or down based on what actually happens. For this 38-year-old woman, a 5 percent error on 1850 calories is 92 calories a day.
What is the difference between BMR and TDEE?
BMR is what your body burns at rest. TDEE adds the calories you use moving and exercising. It is always higher. For this woman aged 38 at 150 lb, BMR is 1345 calories and TDEE at the lightly active level is 1850.