For most people, losing weight involves a combination of factors: regular exercise, nutritious eating, proper hydration, stress management, and quality sleep (along with many other factors.) Ultimately, creating a calorie deficit through one or more of these factors is a requirement for weight loss. While many people understand the importance of staying active and balancing their plates with protein, vegetables, carbs, and healthy fats, fewer truly grasp the concept of calorie deficit.
There are many debates about how many calories one should consume in a deficit and how long the body should operate on such a restricted intake.
In this article, we’ll debunk common myths surrounding calorie deficits and guide you toward a sustainable approach that helps you shed a few pounds while staying energized throughout the day.
What Is a Calorie Deficit?
If you’re in a calorie deficit, it means you burn more calories than your body actually receives. Calories that you consume come from food and drinks, but their expenditure is divided into three main components:
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Basal Metabolic Rate (BMR): BMR refers to the calories burned to keep you alive, meaning spent on functioning your lungs, heart, brain, etc. Your BMR accounts for approximately 10% of the calories you burn throughout the day.
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Thermic effect of food (TEF): The calories your body burns digesting, absorbing, and metabolizing food. Digesting and absorbing the nutrients in your food burns roughly 10% of your total caloric burn throughout the day.
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Activity Energy Expenditure (AEE): AEE refers to the calories spent in movements, such as exercising, walking, cleaning around the house, etc. This includes calories you burn through both formal workouts as well as daily movement. AEE accounts for about 80% of the calories you burn throughout the day.
Hence, a calorie deficit occurs when your body burns more calories than you consume on average. You might be wondering the magic question—“How many calories should I consume to create a deficit?” The answer to this question depends on multiple factors for each person. Having said that, we should also consider other factors that affect weight changes, including hormones, stress, health conditions, sleeping habits, and more.
Metabolic Adaptation During Calorie Deficit
Judging from how our body burns calories, to be in a calorie deficit, one should either exercise more or eat less, right? Yes, but there is a catch.
When your body notices it is burning more calories than it is supposed to, it triggers metabolic adaptation. Metabolic adaptation occurs when your body lacks calories for a sustainable amount of time and slows your metabolism down to keep you alive.
However, metabolism adaptation can also happen during muscle loss. When you don’t consume enough calories from protein sources, the first to go is not your belly fat but your muscles. Why should you be concerned? Because the more muscle tissue you have, the more calories you burn, so maintaining good muscle mass is directly linked to your BMR rate. Therefore, try to incorporate a wide variety of protein sources while in a calorie deficit to maintain and preserve lean muscle mass.
❗If you’re looking for the best way to enter a calorie deficit, some people find it beneficial to first go through the maintenance phase.
Maintenance Phase Before Calorie Deficit
Maintenance calories are the ones you consume to stay the same weight, i.e., maintained.
❗To prepare your body for weight loss during a calorie deficit, some people find it helpful to eat at maintenance or even in surplus for about 3 to 5 months. This way, if your body is adapted to your chronic diet, regular eating without any restrictions will help to slightly increase your metabolism.
How Long Can You Stay in a Calorie Deficit?
Being in a calorie deficit isn’t a sustainable, lifelong diet where you consistently eat less to lose weight. Instead, it’s a temporary phase that helps you shed excess weight while maintaining a healthy and sustainable lifestyle.
Staying in a calorie deficit for too long can lead to negative effects such as decreased energy levels, hormonal imbalances, and loss of muscle mass. Additionally, your body may adapt to the lower calorie intake, slowing your metabolism and making further weight loss even more challenging.
The ideal duration of a calorie deficit depends on individual factors such as starting weight, goals, and overall health. Generally, it is recommended to maintain a deficit for 8–12 weeks before transitioning to a maintenance phase. This allows your body to recover, sustain energy levels, and prevent long-term health issues. Oftentimes, our clients at Strong with Sarah coincide maintenance weeks with fun times throughout life, such as holidays, vacations, anniversaries, birthdays, etc.
❗Remember, a calorie deficit should be part of a well-rounded plan that includes balanced nutrition, regular physical activity, and enough rest to support your overall well-being.
