Maintenance calories after weight loss, and how to find yours

What are maintenance calories, and why do they drop after weight loss?

Maintenance calories are what you can eat on an ordinary day without gaining or losing. Most of that goes on the energy your organs use at rest. The rest is spent digesting food and moving, from climbing stairs to carrying shopping home. A lighter body costs less to run and less to move, so both the resting part and the moving part shrink as weight comes off.

Hall and colleagues at the US National Institutes of Health modelled how body weight responds to a lasting change in food. Their working rule is that a change of about 100 kilojoules a day, roughly 24 calories, moves weight by about a kilo in the long run. Half of that change shows up within about a year.

Run the rule backwards and it explains a lot about life after a diet. A body ten kilos lighter needs roughly 240 fewer calories a day to stay there. Go back to the portions you ate before the diet and you drift back towards your old weight. It happens over months, so the regain rarely feels connected to any one meal.

Sources: [1]

How do you calculate maintenance calories after weight loss?

Use the same arithmetic as any calorie calculator, but with today's weight. For women, resting burn = 10 × weight in kg + 6.25 × height in cm − 5 × age − 161. For men, the last term is + 5 instead of − 161.

Then multiply by an activity factor. Use 1.2 if you sit most of the day and walk fewer than about 5,000 steps. Use 1.375 for 5,000–10,000 steps, or two or three workouts a week. Keep 1.55 for people who are on their feet most of the working day or train hard on most days. These bands are a convention, so pick the lower one when in doubt.

Mifflin and St Jeor built the resting equation in 1990 from measurements in 498 adults. Most online calculators still run it, including the energy needs calculator under Read next. For any one person it can be off by a couple of hundred calories in either direction.

Take Sunita, a 42-year-old teacher in Lucknow who is 158 cm tall. She went from 82 kg to 70 kg over nine months. At 82 kg her resting figure was about 1,437 calories; at 70 kg it is about 1,317. She walks to school and back, so at 1.375 her old maintenance was about 1,975 and her new one is about 1,810. Sunita is an illustration, so put your own numbers in as you read.

That 1,810 is what a calculator would give a woman who has always weighed 70 kg. Sunita has just come off a diet, which changes things a little for the next few weeks.

Sources: [2]

Is your metabolism slower than the calculator says?

Often a little, for a while. In 1995 Leibel and colleagues kept adults at 10–20% below their starting weight in a metabolic ward and measured every calorie they burned. Daily energy use fell more than the smaller bodies alone explained, by about 6–8 calories per kilo of lean mass. For a woman with 45 kg of lean tissue, that is roughly 270–360 calories a day.

Most of that extra drop came from activity, not from rest. After weight loss, muscles do the same everyday work with less fuel. Rosenbaum and colleagues later found the same lower burn in people who had held a 10% loss for more than a year.

Other researchers find a smaller and shorter effect. Martins and colleagues measured resting burn in 71 adults after an eight-week diet. The gap below predicted was about 92 calories at the end of dieting and about half that after four weeks of steady weight. By one year it had faded, and it did not predict who regained.

Part of the difference is what was measured. Leibel's team counted everything a body burns in a day, including movement. Martins's team measured only resting burn, which changes less. Read together, the studies suggest the gap is biggest straight after a diet and narrows once weight has been steady for a while. So right after a diet, aim a little below the calculator and adjust from there.

The extreme case shows how large adaptation can get after an aggressive loss. Fothergill and colleagues followed 14 contestants from a televised weight loss contest. They had lost an average of 58 kg over 30 weeks, and six years later their resting burn was still about 500 calories below prediction.

Sources: [3], [4], [5], [6]

How do you move from a deficit to maintenance without regaining?

There are two reasonable ways in. Some people go straight to the calculator figure minus 100 or so and adjust. Others climb in steps from their diet intake. No trial shows that one method keeps more weight off than the other. Climbing simply makes it harder to overshoot.

Here is what climbing looked like for Sunita, who had been eating about 1,400 calories a day. In weeks one and two she ate about 1,550, adding a roti at dinner and a katori of dahi at lunch. In weeks three and four she moved to about 1,700. Her weekly average fell by 300 g and then held, so she stayed at 1,700.

She called it maintenance once the weekly average had held within about half a kilo for three weeks. Had it kept falling, she would have added another 150.

Daily weights bounce with salt, water, constipation and the menstrual cycle, so judge only the seven-day average. Expect a one-off rise of a few hundred grams in the first week as carbohydrate stores refill with water. It is not fat, and it stops by itself.

Keep weighing once you get there. Wing and colleagues randomised 314 adults who had already lost an average of 19 kg. Those taught to weigh daily and act early on small gains regained less over 18 months. In the control group 72% regained 2.3 kg or more, against 46% in the face-to-face group.

Acting early does not mean panicking at one bad week. If the average climbs about a kilo and stays there for two weeks, with no salty wedding meal or period to explain it, trim 150–200 calories until it comes back down.

Sources: [7]

Weight loss vs maintenance calories: what changes on the plate?

Less than people expect. The gap between losing and holding is usually 300–500 calories a day. A medium roti made from about 30 g of atta is roughly 100 calories, and a katori of toned-milk dahi is around 80–100. In practice the step up to maintenance is a couple of extra rotis and a bowl of dal or dahi.

The foods that took the weight off are still the backbone. A plate built on dal, sabzi, curd, eggs, paneer or fish, with a measured serving of rice or two rotis, fits maintenance with a little more on it. Sweets, fried snacks and sweet chai cups are where the weight tends to come back, mainly because they are easy to eat without counting.

Keep protein where it was during the diet. Cava and colleagues reviewed the trials on muscle during weight loss. A high protein intake and regular exercise, especially resistance work, helped preserve lean mass. Muscle is part of what you burn at rest, so protecting it now keeps your maintenance number from shrinking further.

Sources: [8]

Can you keep losing fat while eating at maintenance?

Sometimes, if you are new to lifting. A beginner who trains two or three times a week and eats enough protein can drop some fat and add some muscle while the scale hardly moves. People call this body recomposition. It shows up first in the waist measurement and in how a kurta or trousers fit, so measure those as well as your weight.

Sunita started with two half-hour sessions a week at home: squats to a chair, wall push-ups, rows with a water bottle in each hand, and lunges. Each week she added a few repetitions. She also made sure every meal had a proper protein serving, whether dal with curd, two eggs, a piece of paneer or fish. Cava and colleagues, reviewing the trials on muscle and weight loss, found that adequate protein and resistance exercise both help hold on to lean mass.

After a long diet, maintenance is also a sensible pause. In the Martins study the gap between measured and predicted burn halved once weight had been steady for four weeks. Hunger usually eases too. If there is more to lose, the next deficit can be shorter.

Longer plans tend to be built this way. The doctor-led plans at Metaboliq begin with a home blood test that a doctor reads with you, and aim for up to 20% of body weight lost with muscle kept. Most people on a goal that size need a holding phase or two along the way, and Sunita's month at 1,700 calories is exactly that kind of phase.

Sources: [5], [8]

Why does hunger rise after a diet, and what helps?

Your appetite hormones take a long time to catch up. Sumithran and colleagues put 50 adults on a ten-week very-low-calorie diet, and they lost an average of 13.5 kg. A year later their leptin was still low and their ghrelin, the hormone that drives hunger, was still higher than at the start. People also rated themselves hungrier.

This is one big reason maintenance needs a plan. Hunger that runs a little higher for a year is hard to out-argue meal by meal.

A few habits blunt it. Eat protein at every meal and start lunch and dinner with a large serving of vegetables. Keep two planned snacks, such as roasted chana, a fruit or a glass of chaas, for the hours when hunger usually peaks. Short nights make evening hunger worse, so protect your sleep. Eating the same few breakfasts on most days also takes decisions off the table.

Sources: [9]

What do people who keep the weight off actually do?

Much of what we know comes from the National Weight Control Registry in the United States, which Wing and Phelan described. Its members had lost an average of 33 kg and kept it off for more than five years. Most said they were active for about an hour a day, ate breakfast, weighed themselves often and ate much the same at weekends as on weekdays. They are volunteers, so this tells you what successful people report, not what caused their success.

When Ostendorf and colleagues measured maintainers with doubly labelled water, the activity turned out to be real. Their 25 adults, each at least 13.6 kg down, spent about 812 calories a day moving. Lean and heavier comparison groups spent about 620–640. Overall the maintainers burned about 2,495 calories a day, close to people still at their old weight.

So these people kept their maintenance number up by moving, and they did not have to live on tiny portions. For Sunita, that might mean keeping the walk to school, adding a 30–40 minute walk after dinner, and holding on to her two strength sessions.

Hall and Kahan's review describes the usual course after weight loss of any kind: a fall, a plateau, then slow regain unless something keeps pushing back. They argue for ongoing support rather than a one-off effort. The registry has encouraging news on timing. Once people had held their loss for two to five years, their odds of keeping it rose sharply.

Sources: [10], [11], [12]