For women, basal metabolic rate (BMR) is estimated with Mifflin–St Jeor: 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161. A 55-year-old woman, 5′4″ and 150 lb, has a BMR of about 1,260 kcal a day. Each additional year of age lowers the estimate by 5 kcal, and each extra 10 lb adds about 45 kcal.
Key takeaways
- A 55-year-old woman who is 5′4″ and 150 lb has a BMR of about 1,260 kcal, which is 1,954 kcal TDEE at a moderate activity level.
- BMR for a 5′4″, 150 lb woman falls from about 1,285 kcal at 50 to about 1,135 kcal at 80, a drop of 150 kcal, or 5 kcal a year.
- Large studies suggest the age effect on expenditure is smaller than the equation implies until about age 60, so body composition matters more than the calendar.
- Protein and strength training are the practical levers for keeping resting energy and muscle.
How this BMR calculator for women over 50 works
Enter your age, weight and height and the calculator returns your BMR with several equations, then your TDEE at each activity level. It starts as female and age 55. This page focuses on women 50 and over. For how all the equations compare and the full explanation, see the main BMR calculator.
What is the BMR formula for women?
Mifflin–St Jeor is the default because it tracks measured resting energy better than older equations (Mifflin et al., 1990; Frankenfield et al., 2005):
BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
What is the BMR by age and weight for women?
This chart is for a woman 5′4″ (162.6 cm) tall, in kcal per day.
| Age | 130 lb | 150 lb | 170 lb | 190 lb | 210 lb |
|---|---|---|---|---|---|
| 50 | 1,195 | 1,285 | 1,376 | 1,467 | 1,558 |
| 55 | 1,170 | 1,260 | 1,351 | 1,442 | 1,533 |
| 60 | 1,145 | 1,235 | 1,326 | 1,417 | 1,508 |
| 65 | 1,120 | 1,210 | 1,301 | 1,392 | 1,483 |
| 70 | 1,095 | 1,185 | 1,276 | 1,367 | 1,458 |
| 75 | 1,070 | 1,160 | 1,251 | 1,342 | 1,433 |
| 80 | 1,045 | 1,135 | 1,226 | 1,317 | 1,408 |
Read down a column to see the age effect (25 kcal for every five years) and across a row to see the weight effect (about 45 kcal for every 10 lb). Weight moves the number more than a decade of age does.
What changes with age?
The equation treats age as a steady 5 kcal per year drop. Real data look different. A doubly labeled water analysis of thousands of people found that, after adjusting for fat-free mass and fat mass, expenditure was fairly stable between about 20 and 60 and declined slowly after that (Pontzer et al., 2021). So if your BMR seems to fall in your 50s, a loss of muscle or lower activity is a more likely culprit than a hormonal “slowdown”.
Menopause is a separate topic. Some research reports changes in energy expenditure and visceral fat across the transition (Lovejoy et al., 2008); see the perimenopause TDEE calculator for what is known. The equation does not include menopause.
How do protein and strength training help?
Lean mass is the main driver of resting energy, so holding on to muscle helps hold on to BMR. Resistance training, together with enough protein, is a well-supported way to do that (Morton et al., 2018). The ranges below use TDEECalc’s protein presets for the 150 lb (68 kg) example:
| Goal | Protein per kg per day | For 150 lb (68 kg) |
|---|---|---|
| Adults over 65 (minimum guide) | 1.0–1.2 g | 68–82 g |
| Regular exercise | 1.2–1.6 g | 82–109 g |
| Building muscle | 1.6–2.2 g | 109–150 g |
Use the protein calculator to find your own range, and check with a doctor if you have kidney disease. Strength training two to three days a week, with all major muscle groups, is a sensible starting point.
How should I use my BMR?
Treat BMR as a floor, not a goal. Multiply it by an activity factor to get TDEE, then set your calories relative to that. For weight loss, a 10–20% deficit from TDEE is typical; see the calorie deficit calculator. Avoid planning below about 1,200 kcal, or below your BMR, without medical supervision. For the general version of this tool, see the TDEE calculator for women and the guide to TDEE vs BMR.
Frequently asked questions
What is a normal BMR for a woman over 50?
For a 5′4″ woman, the equation gives about 1,100–1,550 kcal depending on age and weight: roughly 1,285 kcal at 50 and 1,135 kcal at 80 for 150 lb, and up to about 1,560 kcal at 50 and 210 lb. Your own value depends mostly on your weight and height.
Does BMR drop after 50?
The equation subtracts 5 kcal a year. Measured data are less clear: a large analysis found expenditure adjusted for body composition was stable from about 20 to 60, then declined slowly. Losing muscle can lower BMR more than age itself, which is why strength training matters.
How many calories should a woman over 50 eat?
Multiply BMR by an activity factor. The 55-year-old, 5′4″, 150 lb example needs about 1,733 kcal if lightly active and about 1,954 if moderately active. Use the TDEE calculator for women to include your activity level and goal.
Is BMR the same as calories to lose weight?
No. BMR is your resting burn, and weight-loss targets are set below TDEE, not at BMR. Eating at or below BMR for long periods is not recommended without medical supervision. Use the calorie deficit calculator.
How can I speed up my metabolism after 50?
There is no quick fix. Keeping muscle through strength training and enough protein, staying active, and not crash dieting are the evidence-aligned basics. Metabolic rate is largely set by body size and lean mass.
References
- Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO (1990). A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition 51(2):241–247.
- Frankenfield D, Roth-Yousey L, Compher C (2005). Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults: a systematic review. Journal of the American Dietetic Association 105(5):775–789.
- Pontzer H, Yamada Y, Sagayama H, et al. (2021). Daily energy expenditure through the human life course. Science 373(6556):808–812.
- Morton RW, Murphy KT, McKellar SR, et al. (2018). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine 52(6):376–384.
- Lovejoy JC, Champagne CM, de Jonge L, Xie H, Smith SR (2008). Increased visceral fat and decreased energy expenditure during the menopausal transition. International Journal of Obesity 32(6):949–958.