Calorie needs at age 33, female
Daily calorie needs depend on age, sex, size and how much you move. Here is the sum for a 33-year-old woman who is 5 ft 4 in and 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. This 33-year-old woman uses a factor of 1.375 for the lightly active level.
Worked example
Take a woman aged 33 who is 5 ft 4 in tall and weighs 150 lb. In metric that is 162.56 cm and 68.04 kg. Multiply weight by 10: 10 × 68.04 = 680.4. Multiply height by 6.25: 6.25 × 162.56 = 1016. Subtract 5 × 33 = 165. Subtract 161. That gives 1370.4, which rounds to 1370 calories at rest. Multiply 1370.4 by 1.375 for the lightly active level to get 1884.3, which rounds to 1884 calories a day.
Maintenance calories at every activity level for the same woman aged 33 at 5 ft 4 in and 150 lb, with the lightly active level set in the form above.
- Sedentary (little or no exercise)
- 1644 calories a day
- Lightly active (light exercise 1 to 3 days a week)
- 1884 calories a day
- Moderately active (moderate exercise 3 to 5 days a week)
- 2124 calories a day
- Very active (hard exercise 6 to 7 days a week)
- 2364 calories a day
- Extra active (very hard exercise and a physical job)
- 2604 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 33-year-old woman ranges from 1644 to 2604 calories a day, and the lightly active level gives 1884.
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 1384 calories a day for this 33-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 2134 calories a day for this 33-year-old woman at the lightly active level.
Why does age 33 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 33 that is 165 calories. Without the age term this 33-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 33-year-old woman, a 5 percent error on 1884 calories is 94 calories a day.