Maintenance Calories: What They Are and How to Find Yours

Your maintenance calories are the daily intake at which body weight holds steady over several weeks. A formula estimates it: Mifflin-St Jeor, published in the American Journal of Clinical Nutrition in 1990, explained 71% of the variance in measured resting expenditure. Three weeks of consistent eating and daily weighing measures it.

Key takeaways

• Maintenance is a narrow band rather than one number, because expenditure moves with sleep, illness and how much you walk that day.
• The Mifflin-St Jeor equation came from 498 healthy adults measured by indirect calorimetry, and predicts resting expenditure only.
• Picking an activity multiplier between 1.2 and 1.725 moves the estimate by about 750 calories a day for the same body.
• Weighed food records still understate intake: registered dietitians in a 2002 Journal of the American Dietetic Association study were 223 calories a day low, the other women 429.
• Recalculate after every 10 to 15 pounds of change, because a lighter body costs less to run.

This article is general information for healthy adults, not medical advice, and it does not replace a doctor or a registered dietitian.

What are maintenance calories?

Maintenance is the point where energy in matches energy out, so stored energy neither accumulates nor gets drawn down. Eat above it and weight rises; eat below it and weight falls, which is the mechanism described in what a calorie deficit is.

Two habits of language cause confusion here. Maintenance is not a single number but a narrow band, because expenditure changes with sleep, stress, illness and how much you move on a given day. And maintenance is not the same as resting energy expenditure, which is only the part your body spends staying alive at rest, before any activity is added.

What a formula says your maintenance calories are

The standard estimate comes from the Mifflin-St Jeor equation, published by Mifflin, St Jeor and colleagues in the American Journal of Clinical Nutrition in February 1990. It was derived from 498 healthy adults aged 19 to 78, measured by indirect calorimetry, and it predicts resting energy expenditure from weight, height, age and sex.

Worked through for a 35-year-old woman of 5 feet 6 inches and 160 pounds, the equation returns about 1,440 calories of resting expenditure. Activity is then applied on top as a multiplier.

Activity level	Multiplier	Estimated maintenance for the example
Sedentary, desk job, little exercise	1.2	about 1,730 calories
Lightly active, 1 to 3 sessions a week	1.375	about 1,980 calories
Moderately active, 3 to 5 sessions a week	1.55	about 2,230 calories
Very active, 6 to 7 sessions a week	1.725	about 2,480 calories

The spread across those four rows is 750 calories a day for the same body. That is the size of the guess you are making when you pick an activity level, and it is larger than the deficit most people run. The multipliers themselves are a convention rather than a measured constant, a second reason to treat the output as a hypothesis.

The equation is honest about its own limits. Mifflin and colleagues reported that it explained 71% of the variance in measured resting expenditure, meaning individual results scatter around the prediction even when every input is correct. The National Institute of Diabetes and Digestive and Kidney Diseases publishes a more sophisticated public alternative, the Body Weight Planner, which lets users build personalized calorie and physical activity plans to reach a goal weight and maintain it afterwards.

How to find your maintenance calories by measuring

Three weeks of consistent logging settles the question that no formula can. The procedure is short.

1. Take the formula estimate as your starting intake. Eat close to it every day, including weekends, which are where most weekly averages are lost.
2. Log the same way every day. The absolute accuracy of each entry matters less than using one method throughout, because a constant error still reveals a real trend.
3. Weigh yourself every morning under the same conditions, after waking and before eating, and record the number.
4. Compare weekly averages, never single mornings. Day-to-day weight moves a pound or two on water, sodium and food still in transit.
5. Adjust by 100 to 200 calories a day and repeat for another two weeks. If the average held steady, you have found your maintenance calories. If it drifted up or down by more than a pound over three weeks, move the intake in the opposite direction.

The three-week window is not arbitrary. Hall and colleagues, in the Lancet of August 27, 2011, showed that the bodyweight response to a change of energy intake is slow, with half times of about one year. A single week tells you about water. Three weeks start telling you about energy.

Why your measured number differs from the calculator

The most common reason is not metabolism. It is the log.

Champagne and colleagues put this to a controlled test and published it in the Journal of the American Dietetic Association in October 2002. Ten registered dietitians and ten women of similar age and weight kept 7-day weighed food records while their expenditure was measured with doubly labeled water. The dietitians underreported intake by an average of 223 calories a day. The non-dietitians underreported by 429 calories a day. Every participant was weighing food and trying to be accurate.

That result is worth sitting with, because 429 calories a day is roughly the entire size of a moderate deficit. If your measured maintenance comes out several hundred calories below the formula, the likeliest explanation is that the intake you recorded was lower than the intake you ate. The second likeliest is that your activity level is one row lower on the table above than you assumed.

Maintenance calories are a moving target

The number changes, and it changes in the direction that works against you during weight loss. A lighter body costs less to run, so the intake that maintained 180 pounds is a small surplus at 165 pounds. Recalculate after every 10 to 15 pounds of change rather than trusting a figure from three months ago.

Three other things move it: muscle mass, which raises resting expenditure; daily non-exercise movement, which quietly falls when energy is low; and age, which the Mifflin-St Jeor equation prices at about 5 calories of resting expenditure per year. Protein and resistance training protect the first of those during a deficit, and how much protein per day gives the amounts.

What this article does not cover

This is a method for estimating and then measuring an intake in healthy adults. It does not set a target for any individual, does not apply during pregnancy or breastfeeding, is not for anyone under 18 or with a history of an eating disorder, and does not address thyroid disease, medication effects or any other clinical cause of weight change. Those belong with a physician. If your calculated target sits below roughly 1,200 calories a day, stop and take the question to a clinician instead.

Kalo.Quest is an app on Google Play and the App Store that handles the daily logging this method depends on: photograph the plate and it returns calories, protein, carbohydrates and fat into the day’s journal, or type what you ate instead. It tracks weight over time, shows weekly and monthly averages, and builds a daily goal from your profile. It is free and ad supported, allows up to 30 photo analyses a day with an optional rewarded video for one more, and requires no account. For the target itself, your daily calorie number walks through the arithmetic.

FAQ

How long does it take to find your maintenance calories?

Three weeks of consistent eating and daily weighing, read as three weekly averages. Shorter windows are dominated by water and glycogen shifts rather than by energy balance, which is why a flat week or a heavy week proves very little on its own. If the three weekly averages hold within about a pound, the intake you ate is your maintenance level.

Are maintenance calories the same as TDEE?

In practice they describe the same quantity from two directions. Total daily energy expenditure is what your body spends, and maintenance is the intake that matches it. TDEE is the physiological term used in research; maintenance is the practical term used when setting an intake. Resting energy expenditure is a different and smaller figure, covering only what you burn at complete rest.

Should you eat at maintenance between periods of weight loss?

Eating at maintenance for a few weeks is a normal way to pause a long deficit, and nothing is lost by it as long as the intake really is maintenance rather than an unlogged surplus. It also gives you a fresh measurement at your new body weight, which you need anyway before setting the next target. There is no evidence that a scheduled break is required.