What is a calorie deficit?

For people who are interested in achieving their health goals and making mindful eating choices, this article explains what a calorie deficit is and how it can be a tool for weight management. Learn how to calculate a calorie deficit, ways to reach it and how long it’s safe to stick with it.

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What is a calorie deficit?

A calorie deficit happens when a person uses more calories than they take in from food and drink. The body gets energy (or calories) from what’s eaten and burns that energy to keep everything running. When more calories are burned than consumed, the body taps into stored energy, which can lead to weight loss over time. 

Here are some ways to reach a calorie deficit:

• Eat and drink fewer calories
• Exercise more
• Or both

How to help calculate a caloric deficit

Everyone’s caloric needs are different and depend on factors such as age, biological sex, height, weight and daily activity level. A way to estimate the number of calories someone may need to maintain their current weight is to multiply their weight (in pounds) by 15 if they’re moderately active. (Moderately active means getting at least 30 minutes of physical activity a day from exercising.)

For example, someone who weighs 140 pounds and moves their body for at least 30 minutes a day may need about 2,100 calories daily to maintain that weight. Most experts recommend lowering daily intake by 500 to 1,000 calories. In this case, the person might aim for 1,200 to 1,600 calories per day. People who lose weight gradually are more likely to maintain the weight loss than people who lose weight quickly.

But there’s a limit. In general:

• Women shouldn’t go below 1,200 calories a day.
• Men shouldn’t go below 1,500 calories a day (unless a health care provider says it’s okay). 

For the purposes of this article, “women” and “men” refer to biological sex.

If someone wants to learn about their specific diet needs, they can consult with a dietician or a health care provider

Before trying a calorie deficit plan, it may be helpful to check in with a health care provider. Tools like body mass index (BMI) or waist circumference can also help determine if it’s the right step.

How to help reach a calorie deficit

A calorie deficit can be achieved by making small swaps or changes that add up over time. Below are some ways to help reach a calorie deficit.

Swapping for healthier snacks

Snacking is okay. Making healthy snack swaps each day may help people reduce their calorie intake. But this is only effective when people know what’s in their food. Checking nutrition labels can help people make choices that support their health goals.

Examples of smart, satisfying options that are lower in calories but still filling include:

• Fresh fruit with a small handful of unsalted, dry-roasted nuts
• A cup of grapes and a low-fat cheese stick
• Air-popped popcorn instead of chips

Whole foods, such as fruits, vegetables, nuts, beans and whole grains, can help provide energy. Highly processed foods and snacks with high sodium content should be eaten less often, due to their association with higher risk for various cardiovascular conditions.

Choosing healthier drinks

Many drinks have hidden calories. A soda, flavored latte or even a fruit smoothie can add hundreds of calories without providing a feeling of fullness.

Simple beverage swaps include:

• Black coffee 
• Unsweetened iced tea or sparkling water
• Water with lemon or berries

Alcohol can have a lot of calories. Some cocktails contain over 400 calories, which are mostly from added sugars and syrups.

Physical activity

Moving the body helps burn calories and supports overall health. Finding an activity that feels enjoyable can make it easier to stick with long term. Walking, dancing, biking and even gardening are some examples. Other examples include:

• 150 minutes of moderate activity per week (where talking is easy, but singing is tough)
• 75 minutes of vigorous activity (like jogging or fast-paced cycling)

Using a tracker  

Food trackers can help people learn more about what they eat each day. They show how many calories are in different foods, which can be helpful when someone is trying to eat fewer calories.

Over time, trackers can also show progress and eating patterns, which may help people stay motivated to make healthier long-term choices as they strive to reach their goals.

Other healthy habits  

Beyond food and drink, here are a few ways to help support a weight-management plan:

• Get better sleep. Poor sleep can impact the hormones that regulate hunger.
• Lower stress. High stress may lead to emotional eating or food cravings.
• Check medication. Some medications may cause weight gain. A health care provider can discuss alternatives if needed.

How long can someone be in a calorie deficit?

There’s no one-size-fits-all answer. Some people may need to create a calorie-deficit plan for several weeks or months to achieve their goal, while others may only need a short-term adjustment. What matters most is that people listen to their bodies.

Staying in a calorie deficit for too long can slow down metabolism or lead to lower energy levels. If someone feels overly tired, moody or constantly hungry, these might be signs to adjust their plan. People should be eating enough to get their needed nutrients and stay satisfied.

Key takeaways

A calorie deficit happens when more calories are burned than are taken in, and it can be a helpful tool for weight loss when done safely. Making small food and beverage swaps, engaging in gentle movement and making sure the body still receives the necessary nutrients can be useful. Lasting changes happen slowly, and that can be a good thing. Being kind to the body along the way helps make it easier to stick with a plan and achieve weight-loss goals.

This content is for informational purposes only and is not medical advice. Consult your health care provider before taking any vitamins or supplements and prior to beginning or changing any health care practices.