Calorie needs at age 45, male
Use the form to estimate your maintenance calories. For the sums, read the worked example for a man aged 45 at 5 ft 10 in and 178 lb.
How it works
The page works in two steps. Step one is resting calories with the Mifflin-St Jeor equation: 10 times kilograms plus 6.25 times centimeters minus 5 times age, plus 5 for males or minus 161 for females. Step two multiplies by an activity factor between 1.2 and 1.9. Here the man aged 45 has a height of 177.8 cm and a weight of 80.74 kg, at the lightly active level.
Worked example
Convert first: 5 ft 10 in is 177.8 cm and 178 lb is 80.74 kg. Then 10 × 80.74 = 807.4 and 6.25 × 177.8 = 1111.25. Age 45 takes off 5 × 45 = 225. Add 5. Resting calories are 1698.65, which rounds to 1699. The lightly active factor is 1.375. 1698.65 × 1.375 = 2335.6, or 2336 calories a day.
Maintenance calories at every activity level for the same man aged 45 at 5 ft 10 in and 178 lb, with the lightly active level set in the form above.
- Sedentary (little or no exercise)
- 2038 calories a day
- Lightly active (light exercise 1 to 3 days a week)
- 2336 calories a day
- Moderately active (moderate exercise 3 to 5 days a week)
- 2633 calories a day
- Very active (hard exercise 6 to 7 days a week)
- 2930 calories a day
- Extra active (very hard exercise and a physical job)
- 3227 calories a day
Common questions
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 45-year-old man, a 5 percent error on 2336 calories is 117 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 man aged 45 at 178 lb, BMR is 1699 calories and TDEE at the lightly active level is 2336.
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 45-year-old man ranges from 2038 to 3227 calories a day, and the lightly active level gives 2336.
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 1836 calories a day for this 45-year-old man 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 2586 calories a day for this 45-year-old man at the lightly active level.