A calorie deficit is a person consuming less calories than they burn. A person’s health and circumstances will affect their calorie needs.

A person can create a calorie deficit by consuming fewer calories than they need to maintain their body weight. Over time, this calorie reduction can lead to weight loss.

No single calorie deficit value will ensure weight loss in all people.

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A calorie deficit occurs when a person’s daily consumption of calories is smaller than their daily burn. The body must burn a certain number of calories to perform all its functions daily.

How many calories a person needs each day variesTrusted Source based on their:

  • sex
  • age
  • physical activity levels
  • height
  • weight
  • body composition

Here are some estimated calorie needs for adults ages 19 years and overTrusted Source:

Males
AgeSedentaryModerateActive
19–202,6002,8003,000
21–252,4002,8003,000
26–352,4002,6003,000
36–402,4002,6002,800
41–452,2002,6002,800
46–552,2002,4002,800
56–602,2002,4002,600
61–652,0002,4002,600
66–752,0002,2002,600
76+2,0002,2002,400
Females
AgeSedentaryModerateActive
19–252,0002,2002,400
26–301,8002,0002,400
31–501,8002,0002,200
51–601,6001,8002,200
61+1,6001,8002,000

A person can create a calorie deficit by reducing the number of calories they eat, increasing their activity levels, or both.

There are several ways to determine how many calories a person typically burns daily.

For example, they can manually calculate their daily calorie needs or find an online calculatorTrusted Source.

To perform a manual calculation, moderately active people can multiply their current body weight by 15 to estimate how many calories they need each day. Anything less than this is a deficit.

Basal metabolic rate

People can also use their basal metabolic rate (BMR) and activity levels to determine their caloric needs. They can use the following formula to estimate their BMR:

  • Adult male: BMR (kcal/day) = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
  • Adult female: BMR (kcal/day) = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161

Once a person has their BMR, they can use one of the following formulas, based on their activity levels, to determine their caloric need:

  • Sedentary: little or no exercise = BMR x 1.2
  • Minimally active: 1–3 days per week of exercise or activity = BMR x 1.375
  • Moderately active: 3–5 days per week of moderate activity or sports = BMR x 1.55
  • Very active: 6–7 days per week of hard exercise = BMR x 1.725
  • Extra active: athletes who train twice per day, for example = BMR x 1.9

People can also ask their doctor or nutritionist for the most accurate caloric intake estimates. These professionals can tailor the estimate based on the person and their lifestyle.

Once a person knows how many calories they need each day or week, they can work on creating a calorie deficit.

Diet

One component of creating a calorie deficit is changing what one eats and drinks daily. One should focus on foods that are rich in nutrients but low in calories.

According to the Dietary Guidelines for Americans 2020–2025Trusted Source, a healthful eating pattern with fewer calories should include:

A person should also avoid consuming sugary drinks and trans fats.

Exercise

An essential part of weight loss is exercise. An inactive person should try to increase their daily activity levels.

The Centers for Disease Control and Prevention (CDC)Trusted Source recommends 150 minutes of moderate activity and two sessions of strength training per week to maintain a moderate weight. The more physically active a person is, the more calories they will burn. This increases the number of calories they need, making creating a deficit easier.

This can include activities such as:

  • walking
  • taking the stairs instead of the elevator
  • hiking
  • playing sport
  • biking

Plainly, a calorie deficit is essential to lose weight. However, this may not occur consistently, and many factors can impact weight loss progress.

Reducing calorie intake, hormonal changes, water retention, and alterations in fat storage can cause people to stay the same numerical weight. However, this does not mean a person is not experiencing body composition changes.

Cutting calories is an essential part of weight loss, but it is not the only consideration to make.

  • Calorie counting risks: Calorie counting is not always necessary for weight management, and in some cases, it may be counterproductive or harmful.
  • Activity benefits: Increasing activity levels has numerous benefitsTrusted Source aside from weight management. Strength and cardiovascular training can improve joint health, bone density, and heart function and boost mood.
  • Dietary consideration: When reducing overall calories, a person must maintain adequate nutritional intake. If limited incorrectly, this can lead to harmful nutritional deficiencies.

People should avoid cutting too many calories. People should also avoid losing more than 2 lb each week.

If people cut too many calories and do not get enough necessary nutrients, they can experience health problems.

The body needs a minimum number of calories to function correctly. Cutting too many can increase the risk of health issues, including:

  • not getting enough nutrients, which can interfere with gaining or maintaining bone mass
  • depriving the brain of necessary energy
  • decreasing metabolism
  • increasing the risk of developing gallstones

Some symptoms of not consuming enough calories include:

Before cutting calories, a person should talk with their doctor or nutritionist. People with specific health conditions, such as diabetes, may need specialized diets to help them manage their condition.

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How do I figure out my calorie deficit?

A calorie deficit is the sum of a person’s energy expenditure minus their energy intake. Some online calculatorsTrusted Source can help to estimate this.

Is a 1,200 calorie deficit good for weight loss?

A 1,200 calorie deficit can lead to weight loss. However, large calorie deficits, or sudden changes in them, can lead to adverse health effects and may even result in long-term weight gain.

How much calorie deficit is safe for weight loss?

A person’s age, sex, weight, and many other factors can affect their calorie needs, so it will vary for each person.

Creating a calorie deficit may be helpful if a person wishes or needs to lose weight. A person can do this using a combination of diet and exercise.

They should try to focus on eating highly nutritious foods, drinking more water, and exercising regularly.

Formulas and online calculators are available to help people estimate how many calories they burn per day. From there, people can estimate how many calories they should eat to create a calorie deficit.

A person should aim to lose no more than 1–2 lbs per week to avoid potential health issues associated with insufficient nutrients.