Weight loss is a journey that many people embark on at some point in their lives. Whether it’s to feel more confident, improve health, or fit into a favorite dress, the desire to shed excess pounds is a common goal. Amidst the plethora of diets and exercise plans, the fundamental truth remains: the math of weight loss success is simple. Knowing your numbers will allow you to make choices between different exercises and diet methods to fit your life. For example purposes we’ll also run through a basic scenario for a woman’s average caloric requirements and the steps needed to lose a targeted 20 pounds through a combination of diet and exercise.
The Calorie Equation
At the core of weight loss is the calorie equation, which is grounded in the principle of energy balance:
Calories In – Calories Out = Change in Stored Calories >>> Weight Change
In simpler terms, when you consume more calories than your body expends, you gain weight. Conversely, when you burn more calories than you consume, you lose weight. This concept is underpinned by the first law of thermodynamics, which states that energy cannot be created or destroyed but can only change forms.
Understanding Calories In
“Calories In” refers to the number of calories you obtain from the foods and beverages you consume. To initiate weight loss, it’s essential to consume fewer calories than your body requires to maintain its current weight. This creates a calorie deficit, prompting your body to utilize its stored energy reserves, primarily fat, to compensate for the shortfall.
Determining your daily caloric needs involves considering factors like:
- Basal Metabolic Rate (BMR): This represents the calories your body requires to perform essential functions at rest, such as breathing and maintaining body temperature. BMR typically accounts for the majority of your daily energy expenditure (around 60-75%).
- Physical Activity: Calories burned during physical activities, including both exercise and daily movements, contribute to your total energy expenditure.
- Thermic Effect of Food (TEF): The energy expended during the digestion and absorption of food is a component of “Calories Out.” Different macronutrients (carbohydrates, proteins, and fats) necessitate varying energy levels for processing.
By calculating your BMR and factoring in your physical activity level, you can estimate your total daily energy expenditure (TDEE). Creating a calorie deficit involves consuming fewer calories than your TDEE, typically by reducing your daily calorie intake and/or increasing physical activity.
Sadly there is no automatic counter which will passively track your calorie intake. To really get a handle on how much calories you take in daily, you need to actively track it. It doesn’t need to be a lot of work with lots of available helpful tools (food scales, food tracking apps, calorie reference guides, etc.) but it is an important step in learning how you eat. If you have ever struggled with losing weight, then taking steps to tracking your eating will unlock if you are doing enough to make your strategy work. Nothing is more frustrating than making changes to your diet and not getting the results you want. This step can be the difference that helps you see what is working and what is not.
Understanding Calories Out
“Calories Out” denotes the calories your body expends in various ways, which include:
- Basal Metabolic Rate (BMR): As mentioned earlier, your BMR constitutes a significant portion of calorie expenditure. It implies that your body burns calories even when you’re at rest due to the necessity of sustaining vital functions.
- Physical Activity: Calories burned through exercise and daily activities contribute substantially to “Calories Out.” Regular physical activity can significantly elevate your overall calorie expenditure.
- Thermic Effect of Food (TEF): Although a smaller part of “Calories Out,” the energy required for digesting, absorbing, and processing consumed food still contributes to your overall calorie expenditure.
- Non-Exercise Activity Thermogenesis (NEAT): NEAT encompasses calories burned during non-exercise activities like walking, fidgeting, and standing. Elevating NEAT can substantially impact daily calorie burn.
To lose weight, it’s necessary to create a calorie deficit by either reducing “Calories In” through dietary changes or increasing “Calories Out” via exercise and physical activity. The best strategies are anchored in handling the intake of calories and then adding exercise to round out your efforts. The reason for this is that exercise is significant additional time and effort which may end up being completely offset by poor eating habits. If you fix your eating habits first, you won’t be working against yourself when you add exercise to your routine – in fact, you’ll be supercharging your efforts by creating a greater deficit. Some people who are already happy with their progress from the controlling of their inputted calories then use the deficit room to add back some things they gave up in the process (like alcohol or splurge meals) which can rebalance your lifestyle into something more sustainable. Exercise can then be an important way to help keep a balanced approach to maintaining long term sustainable changes to your diet and lifestyle.
Setting Realistic Goals
Before diving into the practical example, it’s essential to establish realistic weight loss goals. Weight loss isn’t solely about numbers; it’s influenced by individual factors such as genetics, hormonal variations, and personal preferences. Setting achievable goals helps maintain motivation and ensures long-term success. Here are some key points to consider:
- Sustainable Calorie Deficit: Avoid extreme calorie restriction, which can lead to nutrient deficiencies and muscle loss. Aim for a moderate calorie deficit that facilitates steady, sustainable weight loss.
- Gradual Progress: Healthy weight loss typically ranges from 0.5 to 2 pounds per week. Rapid weight loss can result in muscle loss and a higher likelihood of regaining lost weight.
- Body Composition: Shift the focus from just the number on the scale to changes in body composition, including muscle gain and fat loss. This approach has a more profound impact on overall appearance and health.
- Lifestyle Compatibility: Choose dietary and exercise strategies that align with your lifestyle and preferences. Changes which you can stick with are more likely to lead to long-term success.
Practical Example for Weight Loss
Now, let’s dive into practical examples of a woman’s average caloric requirements and how to lose 20 pounds through a combination of dietary changes and exercise:
Step 1: Determining Daily Caloric Needs
Meet Sarah, a 35-year-old woman who weighs 160 pounds, is 5 feet 6 inches tall, and leads a moderately active lifestyle. She wants to find out her TDEE to maintain her current weight.
Using an online calculator (e.g., Healthline’s Calorie Calculator), Sarah estimates her TDEE to be approximately 2,000 calories per day. This means she needs around 2,000 calories to maintain her current weight.
Step 2: Creating a Calorie Deficit
Sarah’s goal is to lose 20 pounds. To achieve this, she needs to create a calorie deficit. A common guideline is that a deficit of 3,500 calories results in approximately 1 pound of weight loss. For 20 pounds, she would need a deficit of 70,000 calories (20 pounds * 3,500 calories/pound).
Dietary Changes
Sarah decides to reduce her daily calorie intake by 500 calories, aiming for a calorie intake of 1,500 calories per day (2,000 calories – 500 calories = 1,500 calories). This caloric deficit of 500 calories per day will theoretically result in a weekly weight loss of approximately 1 pound (500 calories * 7 days = 3,500 calories).
Exercise
In addition to her dietary changes, Sarah incorporates regular exercise into her routine. She starts with 30 minutes of moderate-intensity cardiovascular exercise, such as brisk walking, five days a week, burning approximately 250 calories per session. This adds up to 1,250 calories burned per week through exercise.
Combined Approach
By combining dietary changes and exercise, Sarah creates a total weekly calorie deficit of approximately 3,750 calories (dietary deficit + exercise calories burned). This should result in a weekly weight loss of around 1.07 pounds (3,750 calories / 3,500 calories per pound).
Over the course of 20 weeks (140 days), Sarah expects to reach her goal of losing 20 pounds.
Conclusion
Weight loss is fundamentally about creating a calorie deficit by consuming fewer calories than you burn. Understanding the calorie equation and setting realistic goals are essential steps in achieving successful and sustainable weight loss. Track your progress, know your numbers and build a strategy that works for you and your life!
