Calorie needs at age 40, female
TDEE is the number of calories you burn in a day. This page works it out for a 40-year-old woman at 5 ft 4 in and 150 lb, then shows how it changes with activity.
How it works
Start with resting calories from Mifflin-St Jeor. Take 10 times weight in kilograms and add 6.25 times height in centimeters. Subtract 5 times age. Then add 5 for males or subtract 161 for females. Multiply by an activity factor to get daily calories. Here the woman aged 40 has a height of 162.56 cm and a weight of 68.04 kg, at the lightly active level.
Worked example
For a woman aged 40, weight is 68.04 kg and height is 162.56 cm. Weight gives 10 × 68.04 = 680.4. Height gives 6.25 × 162.56 = 1016. Age takes off 5 × 40 = 200. Subtract 161. Resting calories are 1335.4, or 1335 when rounded. Multiply by 1.375 for the lightly active level to get 1836.2. That rounds to 1836 calories a day.
Maintenance calories at every activity level for the same woman aged 40 at 5 ft 4 in and 150 lb, with the lightly active level set in the form above.
- Sedentary (little or no exercise)
- 1602 calories a day
- Lightly active (light exercise 1 to 3 days a week)
- 1836 calories a day
- Moderately active (moderate exercise 3 to 5 days a week)
- 2070 calories a day
- Very active (hard exercise 6 to 7 days a week)
- 2304 calories a day
- Extra active (very hard exercise and a physical job)
- 2537 calories a day
Common questions
Which activity level should I pick?
Pick the one that matches a typical week, not your best week. If you sit most of the day and train a few times, lightly or moderately active is usually closer than very active. Across the five levels this 40-year-old woman ranges from 1602 to 2537 calories a day, and the lightly active level gives 1836.
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 1336 calories a day for this 40-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 2086 calories a day for this 40-year-old woman at the lightly active level.
Why does age 40 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 40 that is 200 calories. Without the age term this 40-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 40-year-old woman, a 5 percent error on 1836 calories is 92 calories a day.