How to calculate your calorie deficit for weight loss

If you're trying to lose weight, one of the most productive things you can do is to create a calorie deficit [6]. It's no secret that a poor diet with too many calories will create a calorie surplus, which will inevitably lead to weight gain [7].

When you consume fewer calories than your body is using in a day, this creates a calorie deficit that will help you lose weight.

But how many calories should you be consuming for healthy weight loss? And will eating fewer calories be enough to see the results you want, or is there more involved?

Ahead, we'll break down everything you need to know about calorie deficits, including what it is, how to calculate yours, and the role that eating a healthy diet and exercising regularly will play in helping you to lose weight and keep it off.

What is a calorie deficit?

Calorie deficits occur when you consume fewer daily calories through food and drink than your body burns over a given period.

This imbalance is a fundamental principle in weight loss, as it forces your body to tap into its stored energy (typically in the form of body fat) to meet its energy needs [1][6].

There are 2 main ways to create a calorie deficit. You can lower the number of calories you consume daily or increase your physical activity to burn more calories off (or do a combination of both).

When you consistently maintain a calorie deficit, your body will begin to use its stored energy reserves, which will help you lose weight and body fat over time.

It's important to approach a calorie deficit in a healthy and sustainable way, ensuring that you still meet your body's nutritional needs. Extremely low-calorie diets or excessive calorie restrictions can have adverse effects on your metabolism, energy levels, muscle mass, and overall well-being.

How to calculate your calorie deficit

To calculate calorie deficit, you first need to determine your maintenance calories — the number of calories you would need to maintain your current weight.

Here are 3 general steps to calculate a calorie deficit:

1. Calculate your Basal Metabolic Rate (BMR)

Your basal metabolic rate is how many calories your body needs to perform its most essential functions. This is based on factors like your age, gender, weight and height, and can be estimated online [4].

2. Determine your Total Daily Energy Expenditure (TDEE)

Your total daily energy expenditure takes your usual level of physical activity into account.

This is important because, as an example, someone who is spending hours on their feet for work will require more calories a day than someone who lives a more sedentary lifestyle.

To determine your TDEE, you will multiply your BMR by an activity factor representative of your usual daily activity (sedentary, lightly active, moderately active, very active) [5].

3. Calculate a calorie deficit and set your new daily calorie intake

A calorie deficit occurs when you consume fewer calories than your TDEE.

Usually, people create a calorie deficit by subtracting 500-1000 calories from their daily caloric intake.

However, it's important to keep in mind that it's generally not recommended to go below 1200 calories per day for women or 1500 calories per day for men unless supervised by a healthcare professional.

How to create a calorie deficit

In order to create a calorie deficit, you can reduce your calorie intake, increase your physical activity and exercise, or both.

After you've calculated your BMR and factored in your estimated TDEE, you'll have a rough estimate of your body's daily caloric needs. Then, you can create a calorie deficit, which will help you to lose weight.

As for how many calories you should cut from your daily net calories, it's best to aim for a modest, realistic calorie deficit. Common dietary guidelines recommend a deficit of 500-1000 calories per day, which can lead to a weight loss of about 1-2 pounds per week [9].

However, there's more to a calorie deficit than just consuming fewer calories.

You can also increase your deficit by increasing your physical activity, which will increase your number of calories burned. Regular cardio and strength training, like lifting weights, can improve overall health and fitness, and have a big impact on how much weight you lose.

Beyond diet and exercise, it's also important to stay hydrated — because thirst cues can be mistaken for hunger — and get enough sleep. Inadequate sleep can negatively impact your metabolism and increase cravings for high-calorie foods.

As with everything, consistency is key, so it's better to create a calorie deficit that you can stick to over time.

Start by eating fewer calories, and assess your progress over time. You can adjust your calorie deficit plan if you're not dropping weight as expected, but be patient.

How long does it take to see results in a calorie deficit?

Losing weight is different for everyone, but the reality is that sustainable, healthy weight loss takes time, regardless of how many calories you're eating daily.

The amount of time it will take to see the results of a calorie deficit will vary from person to person.

Your personal rate will depend on several factors, including how much of a calorie deficit you're implementing, as well as your starting body weight, metabolism, genetics, and overall lifestyle.

It's important to remember that weight loss usually happens in 2 stages [2]. In the first 4-6 weeks, your body goes through a rapid weight loss stage, which is often the loss of carb stores, protein, and water weight.

After that, the maintenance stage begins. While this is slower weight loss, this is also when you'll start to see actual body fat loss [3].

It's essential to approach any diet with realistic expectations and a focus on overall health rather than just rapid results.

And of course, weight loss is not the only indicator of success; improvements in energy levels, fitness, and overall well-being are also important non-scale victories to consider.

Risks of not eating enough calories

While creating a calorie deficit is one of the major keys to losing weight, restricting calorie consumption too much can be detrimental to your overall health [8].

A caloric deficit is crucial to predicting weight loss, but it's equally important to consume enough calories a day to ensure sustainable, healthy weight loss that doesn't impact muscle mass.

The body receives energy from calories, so when you maintain an extreme calorie deficit for a prolonged amount of time, it can actually slow your metabolism down, as your body adjusts to conserve energy [7].

Other potential risks that come with consuming too few calories include nutrient deficiencies and nutrient absorption issues.

Extreme calorie restriction can also lead to gallstones, hormonal imbalances, fatigue, weakness and loss of muscle mass, and a weakened immune system, which can negatively impact overall physical health.

On a mental health front, severe calorie restriction can also contribute to mood swings, irritability, anxiety, and other mental health issues. It can also increase the risk of developing an unhealthy relationship with food, which can evolve into eating disorders.

It's important to approach any diet with a focus on balance, sustainability, and meeting nutritional needs.

If you're considering a calorie deficit or making significant changes to your diet, it's advisable to consult with a healthcare professional or a registered dietitian to ensure that you're taking a safe and effective approach tailored to your individual health needs.

If you're trying to cut calories but don't want to lose muscle tissue or gain weight, one way to ensure that you're getting the nutrients you need without consuming more calories than you need is with Juniper's Nourish Shakes.

With 24 minerals and nutrients, each shake is high in protein and fibre, and contributes up to 30% of your daily vitamin needs for immunity and health overall, all while being low in calories.

Is a calorie deficit enough to lose weight?

Creating a calorie deficit is a fundamental principle for weight loss.

However, it's also important to consider the overall quality of your diet, the types of foods you consume, and the balance of macronutrients (carbohydrates, proteins, and fats).

Your overall health and well-being will be best served by healthy weight loss created by a combination of regular exercise, good hydration, a balanced diet, getting enough rest, as well as a calorie deficit. This will ensure that your weight loss is sustainable over time.

Weight loss is a complex process, and it's one that's influenced by various individual factors, so it can be overwhelming to go it alone. That's where Juniper's Weight Loss Reset Programme can be beneficial.

Juniper's Weight Reset Programme was designed by UK clinicians and dietitians and uses semaglutide, a groundbreaking medication that can help curb overeating, reduce food cravings, and lose weight safely.

When combined with personal, one-on-one support from a health coach who will offer advice and keep you accountable, the Weight Reset Programme is designed to set you up for long-term success.

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