Calorie Deficit: How to Calculate It for Weight Loss
If you’re on your way to lose weight or have been part of the diet culture, you would have been curious to know how weight loss works. Many nutritionists and health coaches use the term “calorie deficit” to explain the underlying principle of their weight loss plans. But what does it mean and how do calculate calorie deficit and implement it without compromising on nutrient intake?
Calories basically refer to energy. When we speak about calories in food, it is the energy we get from our diet that’s under consideration. If you consistently eat more calories than what is required by your body, the excess gets stored as fat.
Now, how do you get rid of this extra fat and lose weight? By creating a calorie deficit. Calorie deficit refers to cutting down a certain number of calories from your usual intake.
You need to consume fewer calories than you burn in order to lose weight. This helps the body create an energy gap. In order to cope with it, your body starts burning glycogen — the stored form of glucose and fat— for energy. Over a period of time, it leads to weight loss.
Now how do you find out how much energy you have burnt? The simplest estimation of total calories burned in a day is through calculating your Total Daily Energy Expenditure (TDEE). This refers to the total amount of energy or calories your body burns every day while performing its regular bodily functions and any physical activity.
Your energy expenditure depends on four things:
1. BMR or Basal Metabolic Rate is the energy your body burns at rest, which accounts for 70% of your total daily energy expenditure
2. NEAT or Non-Exercise Energy Expenditure is the energy you expend during any unplanned activity, such as moving around and doing small chores
3. TEF or Thermic Effect of Food is the energy that is expended to digest and metabolize food
4. EAT or Exercise Activity Thermogenesis is the energy expended through planned physical activity
How to calculate calorie deficit
Once you know your TDEE, figure out how much calorie deficit you need to assume in order to lose weight. Weight loss occurs by energy balance manipulation. You need to accurately gauge how many calories you are consuming and how many you are burning.
Researchers estimate that you need a deficit of 3,500 calories per week to lose about ½ a kg of fat. While this total number seems high, the weekly energy deficit can be reduced to daily losses to make losing weight more manageable. Observing a calorie deficit of 350kcal to 500kcal will ensure a healthy weight loss. In most cases, consuming a 350-500kcal deficit from your TDEE works well in order to lose about 350-500g per week.
How to create a calorie deficit?
So, how do you create a deficit of 500 calories per day or 3,500 calories per week?
The first step would be to figure out how many calories you consume in a day. You can do this by weighing whatever you eat for a few days and tracking your calories to determine your average consumption. Alternatively, seek help from a dietitian or certified nutritionist to help determine your calorie intake.
Once you have figured out your calorie intake, you can create a calorie deficit of 350Kcal-500Kcal by either cutting your current meal portion sizes or reducing any excessive or mindless snacking.
If your calorie consumption seems less than what you are burning, replace some of the foods in your current meal with lower-calorie alternatives.
But if you think reducing more and more calories over time would help you lose weight quickly, think again. Remember that 70% of your calories are burned in important physiological processes. If you stop feeding yourself that minimal energy, you are more likely to feel tired, lethargic, and, let’s not forget, ravenously hungry.
Exercising regularly, which increases energy expenditure, is another way of attaining calorie deficit. This includes any planned workout as well as unplanned activities such as walking around, standing, or doing household chores.
Combining diet and exercise
The most ideal recommendation would be to follow a diet along with an exercise routine. This is the best way to achieve a calorie deficit. Eat 250 fewer calories each day and go for a 60-minute brisk walk or any activity of choice to burn another 250 calories. The calorie deficit would total to 500 calories every day and account for a loss of 3,500 calories by the end of the week.
Slow and steady wins the race
Keep a few things in mind before you embark on your weightloss journey. Less is more, which means focusing on a steady calorie deficit consistently can bring you more sustainable results than a large deficit that’s too quick. The latter may ensure weight loss, but it will not necessarily be in the form of fat.
Ensure you’re not skipping any food groups as a whole, unless recommended by a doctor or a dietitian. Maintaining a balanced diet is key. Crash diets usually promise great results, but may lead to loss of muscle mass or dehydration, both of which adversely affect health in the long run.
Calorie deficit is the most effective underlying principle of any weight loss program. In combination with the right macronutrient split and exercise regime, it’s your ticket to a successful weight loss journey.
1. Melanson EL. The effect of exercise on non-exercise physical activity and sedentary behavior in adults. Obes Rev 2017; 18: 40–9.
2. Hall KD. What is the required energy deficit per unit weight loss? Int J Obes 2008; 32: 573–6.
3. Ostendorf D, Caldwell A, Creasy S, et al. Physical Activity Energy Expenditure and Total Daily Energy Expenditure in Successful Weight Loss Maintainers. Obesity (Silver Spring) 2019; 27: 496–504.