TDEE for Cutting — Men Age 25-29, Lightly Active

A cutting phase means eating below your total daily energy expenditure (TDEE) so the body covers the shortfall from stored fat. The size of the deficit decides how fast weight comes off — and how sustainable the phase feels. For a 25-29-year-old man who is lightly active — light exercise or sport on one to three days a week — the worked example below uses a body weight of 80 kg (176 lb) and a height of 178 cm, and gives a cutting target of 1951 kcal/day — a deficit of about 500 kcal a day below TDEE. That figure is an estimate built from a published formula, not a personal prescription: your own numbers will differ if your weight, height or daily activity differ from the example.

The worked example is the whole point of this page. Rather than quoting a single number with no working, it shows the Mifflin-St Jeor equation step by step, multiplies the result by the activity factor for a lightly active lifestyle, and then turns the total into daily calorie targets for cutting at three deficit sizes. Use the same steps with your own measurements, or use the calculator linked below, and you will get a target matched to you rather than to the example person. Men typically have a higher absolute BMR than women of the same age and weight, because on average a larger share of body weight is muscle, and muscle burns more energy at rest. That is why the men's constant in the formula is +5 rather than −161, and why the safety floor for men is 1,500 kcal a day.

Cutting is not the same as eating as little as possible. A deficit that is too large costs muscle alongside fat, raises hunger, disrupts sleep and is usually abandoned within weeks — and the weight then returns. The standard target on this page, a deficit of about 500 kcal a day, is designed to lose roughly 0.5 kg a week, which sits inside the recommended rate of 0.5–1% of body weight per week. Slower is not failure; it is the pace that keeps muscle and keeps the result.

Calculate your own TDEE

Your weight, height, age and activity level are almost certainly different from the example above, so run your own numbers with the TDEE calculator. It uses the same Mifflin-St Jeor equation and the same activity multipliers shown on this page, and it also gives cutting, maintenance and bulking targets from a single set of inputs. If you only want the resting figure, the BMR calculator gives that on its own, and the weight-loss calculator turns a target rate of loss into a daily calorie figure.

Related pages and tools:

The formula: Mifflin-St Jeor (1990)

The Mifflin-St Jeor equation is the most widely validated formula for estimating resting energy expenditure in adults. It was published by Mifflin et al. in the American Journal of Clinical Nutrition in 1990 (Mifflin MD et al., Am J Clin Nutr 1990;51(2):241–247), and it is the equation most calculators and many clinical settings use as a starting point. For women it is:

BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) − 161

For men the final term is +5 instead of −161. TDEE is then the BMR multiplied by an activity factor: 1.2 for sedentary, 1.375 for lightly active, 1.55 for moderately active, 1.725 for very active and 1.9 for extremely active. These multipliers are the standard values used with the Mifflin-St Jeor equation, and the World Health Organization (WHO) BMI categories are the reference used later on this page for the example person's body mass index.

Working through the example for a 25-29-year-old man at 80 kg and 178 cm, using age 27 (the midpoint of the 25-29 band):

  • 10 × 80 kg = 800 kcal
  • 6.25 × 178 cm = 1112 kcal
  • 5 × 27 years = 135 kcal
  • Constant: 5 kcal

So BMR = 800 + 1112 − 135 +5 = 1782 kcal/day. That is the energy the body would use at complete rest, before any movement, digestion or exercise is counted. Multiplying by the lightly active factor of 1.375 gives TDEE = 1782 × 1.375 = 2451 kcal/day. The example person's BMI is 80 ÷ (1.78 m)² = 25.2, which the WHO categories place in the overweight range — a screening figure only, not a diagnosis, and it cannot tell muscle from fat.

Your targets at a glance

Figure Value
BMR (Mifflin-St Jeor) 1782 kcal/day
Activity level lightly active (×1.375)
TDEE 2451 kcal/day
Cutting target (standard) 1951 kcal/day
Actual deficit about 500 kcal/day
Expected loss about 0.45 kg/week
Safety floor 1500 kcal/day (men)

How activity level changes the number

The same 25-29-year-old man at 80 kg and 178 cm has the same BMR of 1782 kcal/day whatever the lifestyle — but TDEE moves a lot with activity:

Activity level Multiplier TDEE
Sedentary 1.2 2139
Lightly Active 1.375 2451
Moderately Active 1.55 2763
Very Active 1.725 3075
Extremely Active 1.9 3387

The gap between sedentary and extremely active is 1248 kcal a day for this person, which is why two people of the same age, sex, weight and height can need very different calorie intakes. It is also why activity level is the input people most often get wrong: be honest about a typical week, not your best week. Lightly active covers the large middle group who move a little most days — a few gym sessions or walks a week on top of a mostly seated day. It is the right choice if you exercise lightly one to three days a week.

Cutting targets: mild, standard and aggressive

One deficit does not suit everyone. A smaller deficit is easier to live with and preserves more muscle; a larger one loses weight faster but is harder to sustain and risks more muscle loss. Here are the three standard options for this profile, all measured against a TDEE of 2451 kcal/day:

Deficit Daily target Expected loss Held at safety floor?
Mild (−250 kcal/day) 2201 0.23 kg/week No
Standard (−500 kcal/day) 1951 0.45 kg/week No
Aggressive (−750 kcal/day) 1701 0.68 kg/week No

The standard target of 1951 kcal/day is the default recommendation on this page because a deficit of about 500 kcal a day produces roughly 0.45 kg of loss a week for this profile — inside the recommended 0.5–1% of body weight per week, which for 80 kg is 0.4–0.8 kg a week. The mild target suits people who want the easiest possible cut, who train hard and want maximum muscle retention, or who have already been dieting for a while and need a break from a bigger deficit. The aggressive target should only be used for short periods by people with plenty of body fat to lose, and never below the safety floor.

What this means at your age

The late twenties are often when incidental movement starts to fall: student days of walking everywhere give way to a desk, a commute and a settled routine, while social eating and drinking stay frequent. Resting metabolic rate is still high, so a cut works well, but the deficit has to be planned rather than assumed — the days of staying lean without thinking about it are ending. Strength training two to four times a week is the highest-value habit to add now, because muscle built in the twenties is far easier to keep than muscle built later.

For this 25-29 profile specifically, the numbers tell a consistent story: a BMR of 1782 kcal/day and a TDEE of 2451 kcal/day at lightly active activity leave a cutting target of 1951 kcal/day. That is not a small amount of food — it is a normal day of eating with the surplus trimmed off — and it should still include enough protein, which for 80 kg at 1.6–2.2 g per kilogram is 128–176 g a day, or roughly 32–44 g per meal across four meals. Spreading protein across meals matters more than hitting a single daily total, because muscle protein synthesis responds to each meal. Kidney disease changes the protein answer, so anyone with kidney problems should follow their doctor's guidance rather than these general ranges.

How to use the 1951 kcal target

Start at 1951 kcal a day and hold it for two to three weeks before changing anything. Weigh yourself three to four times a week, first thing in the morning, and compare weekly averages rather than single days — daily weight moves by a kilogram or more with water, glycogen and food volume. If the weekly average is falling by about 0.45 kg a week, the target is working. If it is flat for two full weeks, trim another 100–150 kcal a day, or add a daily walk, rather than slashing calories.

A rough split of the 1951 kcal target across the day looks like this:

Meal Calories
Breakfast 488
Lunch 585
Dinner 585
Snacks 293

Plan the deficit around real life, not around perfection. A single higher-calorie day does not undo a week of steady eating, and a single low day does not accelerate fat loss in a meaningful way. What matters is the weekly average. Keep resistance training in the programme two to four times a week; the deficit does the fat loss, the training tells the body to keep muscle. And if 1951 kcal feels very low day to day, remember the safety floor: never go below 1500 kcal a day (men) without medical supervision, and never chase a faster rate than about 0.5–1% of body weight per week. Recalculate every 5 kg of weight change, because a lighter body burns fewer calories and a target set at your old weight gradually becomes a surplus.

What this number does not tell you

A TDEE estimate is a starting point, not a measurement. The Mifflin-St Jeor equation was validated on population averages, and individual resting metabolic rate varies by roughly ±10% around the prediction because of differences in muscle mass, genetics and health. Two people with identical age, sex, weight and height can have BMRs a few hundred calories apart. The equation also uses total body weight, so it is less accurate for very muscular people (it underestimates) and for people with a high body-fat percentage (it overestimates), because muscle burns more energy at rest than fat does.

Activity multipliers are blunt by design. They compress a whole week of movement, training, work and fidgeting into a single number, and they cannot capture a week that mixes desk days with long hikes, or a job that is physical some days and sedentary on others. Food intake itself also costs energy to digest — the thermic effect of food, roughly 10% of intake — which the multiplier approach folds in approximately rather than measuring. The lightly active label itself is a judgement call: two people who both call themselves lightly active can easily differ by 200 kcal a day in real expenditure. Treat the 1951 kcal target as a hypothesis: follow it for two to three weeks, watch the weekly weight average, and adjust by 100–200 kcal based on what actually happens.

Frequently asked questions

What is the TDEE for a 25-29-year-old man who is lightly active?

For the worked example on this page — 80 kg, 178 cm, age 27 — BMR is 1782 kcal/day by Mifflin-St Jeor and TDEE is 2451 kcal/day at the lightly active multiplier of 1.375. Your own TDEE will differ if your weight, height or activity differ; use the TDEE calculator with your own measurements.

How was the 1951 kcal cutting target calculated?

It starts from TDEE of 2451 kcal/day. A deficit of about 500 kcal a day is subtracted for cutting. The target is an estimate, not a prescription, and the actual deficit works out at roughly 0.45 kg of weight loss a week.

Does TDEE fall as you get older?

Yes, slowly. In the Mifflin-St Jeor equation the age term subtracts 5 kcal a day for every year of age, so BMR falls by about 50 kcal a decade when weight and height stay the same — and in practice it often falls faster because muscle mass and daily activity tend to decline with age. That is one reason strength training matters more, not less, as the decades pass, and why the 25-29 profile on this page has a lower BMR than the same person would have had at 21.

Should I use my current weight or my goal weight in the formula?

Use your current weight. TDEE describes what your body uses now; plugging in a goal weight answers a different question — what you will need once you get there. For this profile that means using 80 kg, not a future weight. Recalculate every 5 kg of weight change or so, because a lighter body burns fewer calories and a target set at your old weight gradually becomes a surplus.

Why is my TDEE different from another calculator's?

Different calculators use different equations (Mifflin-St Jeor, Harris-Benedict, Katch-McArdle) and different activity definitions, so results commonly differ by 100–300 kcal. That spread is normal and is another reason to treat any single figure as a starting estimate and adjust from two to three weeks of real weight data. The 2451 kcal figure here follows Mifflin-St Jeor (1990) with the standard multipliers.

What should I do if I stop losing weight at 1951 kcal?

First check the basics: are you tracking everything, including oils, sauces, drinks and weekend meals, and has your activity actually stayed at the lightly active level? If tracking is honest and weight has been flat for two full weeks, reduce intake by 100–150 kcal a day or add 20–30 minutes of daily walking, then reassess after another two weeks. Never drop below 1500 kcal a day without medical supervision.

Estimates only, not medical advice. Minimum safe intakes: 1,200 kcal/day women, 1,500 kcal/day men — consult a healthcare professional before a very-low-calorie diet.