TDEE Calculator for Women Over 40

A typical 45-year-old woman who is 5'4", 165 lb and lightly active has a TDEE of roughly 1,900 calories per day. Eating at TDEE maintains weight; eating 300 to 500 calories below it produces gradual fat loss of about 0.5 to 1 lb per week.

Mifflin-St Jeor (women): BMR = 10 x weight(kg) + 6.25 x height(cm) - 5 x age - 161 (Mifflin MD et al.)

TDEE: TDEE = BMR x activity factor (1.2 to 1.9) (ADA evidence analysis of RMR prediction equations)

Two things shift in your 40s: muscle mass gradually declines (about 3 to 8% per decade after 30 without strength training), and hormonal changes around perimenopause alter how your body stores fat. Muscle is metabolically active tissue, so less muscle means a slightly lower BMR. The Mifflin-St Jeor equation already accounts for age, which is why your TDEE at 45 is lower than it was at 25 at the same weight.

The practical takeaway is not that weight loss becomes impossible after 40. It means your calorie budget is a little tighter and preserving muscle (protein plus resistance training) matters more than it did at 25.

Eat at your TDEE to maintain weight. To lose fat, subtract 300 to 500 calories: that produces roughly 0.5 to 1 lb of loss per week, a pace that preserves muscle and is sustainable. Never eat below 1,200 calories per day without medical supervision.

Remember TDEE is an estimate with a margin of error around 10%. Track your real-world trend for 2 to 3 weeks and adjust: if your weight is stable at your calculated deficit, your true TDEE is lower than estimated.

Most women over 40 have a TDEE between 1,600 and 2,200 calories per day, depending on weight, height and activity level. A sedentary 45-year-old at 5'4" and 165 lb burns about 1,650 calories; the same woman exercising 3 to 5 times a week burns about 2,140.

Yes. The American Dietetic Association's evidence review found Mifflin-St Jeor the most reliable prediction equation for resting metabolic rate in the general adult population, accurate within 10% for most people. Individual variation still exists, so treat the number as a starting point.

Subtract 300 to 500 calories from your TDEE. For a typical TDEE of 1,950, that means eating 1,450 to 1,650 calories per day for a loss of 0.5 to 1 lb per week. Do not go below 1,200 calories per day without medical supervision.

The menopause transition is associated with a decline in fat-free mass and total energy expenditure, though much of the change tracks with age and activity rather than menopause itself. Strength training and adequate protein offset most of the difference.