Why is it that some people can eat a mountain of food and never gain a pound, while others seem to gain weight just by looking at dessert? The answer lies in understanding energy balance.
Before we dive into what energy balance is, let’s first understand what energy means. Energy comes from food and beverages. We usually measure the energy content of food and beverages using calories—aka the unit of energy. When we consume food, our bodies use the calories it contains to perform various functions like breathing, circulating blood, and physical activity.
Energy Balance
Energy balance is a fundamental concept in weight loss, representing the relationship between calories consumed through food and beverages (calories in) and calories burned through various activities (calories out). By making informed choices about diet and physical activity, individuals can achieve and maintain a healthy weight.
Oh, that sounds easy, right? Just eat less food while maintaining the same amount of exercise, and you should be able to achieve your weight loss goal. That is true, and this basic relationship is simple. However, that doesn’t mean what occurs between calories in and calories out is simple, or that energy balance is easy to change. Many factors can affect energy balance and consequently the results we get.
What Affects Energy Balance?
Calories in can be affected by things such as:
- The type of food we eat
- How those foods are cooked or prepared
- How efficiently and effectively we digest and absorb those foods
- Our hunger, appetite, and satiety signals (and how well we obey them)
- Our sleep, recovery, and stress levels
- Our psychology and mindset
- Our emotions
- And many more factors
Calories out can be affected by:
- Our Basal Metabolic Rate (BMR)
- Our Resting Metabolic Rate (RMR)
- Producing heat (thermogenesis)
- The thermic effect of food (TEF)
- Our exercise and purposeful movement
- Non-exercise movement
- Excretion
- Our sleep, recovery, and stress levels
- Our hormonal status
- Genetic factors
Many of those words are “intangible” for our non-health scientist brains, which in itself already makes the point that energy balance is not as simple as it sounds. We haven’t even touched on the biopsychosocial perspective of our lives.
Calories In – What You Eat
There are three types of calories, also known as macronutrients: carbohydrates (carbs), proteins, and fats. Carbohydrates provide quick energy and can be found in foods like rice, bread, pasta, fruits, and vegetables. Proteins are important for muscle repair and growth and can be found in meat, dairy, beans, and nuts. Fats are essential for energy storage and cell function; found in oils, butter, avocados, and nuts.
We need all of these macronutrients in our meals; therefore, eating a balanced diet with balanced portions of each of them is essential. In supporting weight loss, focus on whole, minimally processed foods that provide essential nutrients and promote satiety. In simple terms, eat foods that are closest to their original forms. Rotisserie chicken is better than chicken nuggets. Eating a whole apple is better than drinking apple juice. Baked potatoes are better than chips. You get the idea.
Practical Tips on Calories In
- Read Labels: Learn to read and understand nutritional labels to make informed choices about the foods you eat.
- Plan Meals: Plan and prepare meals ahead of time to avoid impulsive eating and ensure a balanced diet.
- Mindful Eating: Practice mindful eating by paying attention to hunger and fullness cues, and enjoying each bite.
Calories Out – What You Burn
We touched base on what affects calories out in the previous section. Calories out refers to the number of calories burned through various activities, including basal metabolic rate (BMR), physical activity, and the thermic effect of food.
BMR is the number of calories your body needs to maintain basic physiological functions at rest, such as breathing, circulation, and cell production. Several factors influence BMR, such as age, gender, body composition, and genetics.
Physical activity includes exercise (cardio, strength training) and non-exercise activities (walking, fidgeting, daily chores). Physical activity increases calorie expenditure, supports weight loss, improves cardiovascular health, and builds muscle.
The thermic effect of food is the energy required to digest, absorb, and process the nutrients in the food you eat. Different macronutrients have varying thermic effects, with protein requiring the most energy to process.
Practical Tips on Calories Out
- Increase Activity: Incorporate more physical activity into your daily routine, such as taking the stairs, walking, or engaging in regular exercise.
- Strength Training: Include strength training to build muscle, which can increase your BMR and overall calorie expenditure.
- Active Lifestyle: Aim for a mix of aerobic exercises, strength training, and everyday activities to boost calorie burn.
Creating a Calorie Deficit
A calorie deficit occurs when you burn more calories than you consume, leading to weight loss. It is the fundamental principle of weight management. Achieving weight loss involves creating a calorie deficit, where the number of calories burned exceeds the number consumed. In simpler terms, a calorie deficit can be achieved by eating less food or increasing physical activity to burn more calories.
In short, to lose weight, you need to create a negative energy balance by consuming fewer calories or increasing physical activity to burn more calories. You will need to determine your daily caloric needs based on factors like age, gender, weight, height, and activity level. Use this information to plan a calorie deficit.
Here are a few strategies to help create your calorie deficit strategy:
- Portion Control: Practice portion control to avoid overeating and manage calorie intake effectively. Aim to eat until you’re 80% full during meals. Eating slowly helps give your brain enough time to signal that you are full. Nutrition scientist Sarah Berry mentioned that it takes roughly about 10-20 minutes for your brain to process the satiety (fullness) signal. This is also why eating whole meals is preferable to drinking caloric drinks.
- Healthy Swaps: Make healthier food choices by swapping high-calorie foods with nutrient-dense, lower-calorie options. Include more whole and minimally processed foods in your diet. Foods that are close to their original forms are usually safe options. High-calorie, less nutrient-dense foods include sugary drinks, candy and sweets, pastries and baked goods, fast foods, and more. High-calorie, less nutrient-dense foods are often more desirable due to their highly palatable characteristics, making them easier to consume as they taste delicious.
- Meal Planning: Plan meals ahead of time to ensure balanced and calorie-controlled eating. Along with meal planning, consider a kitchen makeover. Minimize foods that don’t help you move towards your goal. Co-Founder of Precision Nutrition, Dr. John Berardi, introduced a concept called Berardi’s First Law: “If a food is near you and conveniently available, you’ll eventually eat it.” Make the foods that support your goal easily accessible to you.
- Regular Exercise: Engage in regular physical activity, including both aerobic exercises (e.g., walking, running, cycling) and strength training (e.g., weight lifting, bodyweight exercises). Remember to start small. Choose exercises that you love to do and that make you excited to look forward to them.
- Active Lifestyle: Incorporate more movement into your daily routine, such as taking the stairs, walking, or gardening.
There are a few more habits that you can incorporate into your strategy, but I’ll keep it minimal for this article to avoid overwhelming you. Don’t get me wrong; I’m not suggesting you make drastic changes immediately. Take it day by day or even week by week. Focus on the habit first. After all, we want sustainable change that we can maintain long-term rather than a drastic habit change that will only last for a week. Be consistent with your dietary and exercise habits to achieve and maintain a calorie deficit.
Common Myths and Misconceptions
Myth 1:“Eating Late at Night Causes Weight Gain”
Reality: Weight gain is more about the total number of calories consumed versus calories burned, regardless of the time of day. However, late-night snacking can lead to overeating or unhealthy food choices. Additionally, a good night’s sleep is essential for overall health and well-being. Eating late at night can interfere with your body’s natural processes, making it harder to fall asleep and stay asleep. For better sleep hygiene, avoid heavy meals, caffeine, and alcohol before bedtime. Instead, try to have your last meal at least a few hours before going to bed to give your body time to digest and relax. While eating late at night has less impact on weight gain compared to overall calorie intake and expenditure, it does affect your overall health and well-being.
Myth 2:“You Have to Starve Yourself to Lose Weight”
Reality: Starving or severely restricting calories can lead to muscle loss, nutrient deficiencies, and metabolic slowdown. Sustainable weight loss involves a balanced diet and creating a moderate calorie deficit.
Myth 3:“All Calories Are Equal”
Reality: While a calorie is a calorie in terms of energy, the source of calories matters. Nutrient-dense foods provide essential vitamins, minerals, and fiber, whereas empty-calorie foods lack nutritional value.
Myth 4:“Carbs Are the Enemy”
Reality: Carbohydrates are an essential part of a balanced diet. Complex carbs, like whole grains, fruits, and vegetables, provide sustained energy and important nutrients, helping you power through activities and exercises to support your weight loss goals.
Myth 5:“Exercise Alone is Enough for Weight Loss”
Reality: While exercise is crucial for overall health and can aid weight loss, it’s difficult to out-exercise a poor diet. Both diet and physical activity are essential for effective weight management.
Myth 6:“Diet Foods and Drinks Help with Weight Loss”
Reality: Many diet foods and drinks contain artificial sweeteners and other additives that may not support long-term weight loss. Whole, minimally processed foods are generally more beneficial.
Conclusion
While the basic principle of energy balance is simple, the myriad factors that influence it demonstrate that managing energy balance is a complex process. Several factors influence energy balance, including BMR, thermogenesis, lifestyle, biopsychosocial factors, and more.
TL;DR
Understanding energy balance is key to demystifying why some people can seemingly eat a lot without gaining weight, while others gain weight easily. Energy balance represents the relationship between calories consumed (calories in) and calories burned (calories out). Maintaining this balance is crucial for achieving and maintaining a healthy weight.
Energy balance may sound straightforward, but the many factors that influence it make it quite complex:
- Calories In: Influenced by the type of food, preparation methods, digestion efficiency, hunger and satiety signals, sleep, stress levels, psychology, emotions, and more.
- Calories Out: Affected by basal metabolic rate (BMR), resting metabolic rate (RMR), thermogenesis, thermic effect of food (TEF), physical activity, non-exercise movement, excretion, sleep, recovery, stress levels, hormonal status, and genetics.
Why Some People Don’t Seem to Gain Weight:
- High Basal Metabolic Rate(BMR): Individuals with a higher BMR burn more calories at rest. This can be due to genetics, muscle mass, and other factors.
- Efficient Thermogenesis: Some people have a more efficient process of generating heat (thermogenesis), which burns additional calories.
- Active Lifestyle: Engaging in more physical activities, both exercise and non-exercise movements, increases calorie expenditure.
- Effective Appetite Regulation: Better hunger and satiety signals help prevent overeating, maintaining energy balance.
Why Some People Gain Weight Easily:
- Lower Basal Metabolic Rate(BMR): Those with a lower BMR burn fewer calories at rest, making it easier to gain weight.
- Less Physical Activity: Sedentary lifestyles result in fewer calories burned, leading to an energy surplus and weight gain.
- Emotional Eating: Psychological and emotional factors can drive overeating, leading to excess calorie intake.
- Hormonal Influences: Hormonal imbalances, such as those related to thyroid function or insulin resistance, can affect metabolism and weight gain.
While the concept of energy balance is simple, managing it for weight loss requires a comprehensive approach that considers all these factors. By understanding and optimizing both calories in and calories out, individuals can achieve and maintain a healthy weight.
Glossary
Calorie: A unit of energy
Energy Balance: The relationship between energy taken in from food and energy expended through metabolism and activity
Biopsychosocial perspective: A combined biological, psychological, and social understanding of a person and their environment.
References
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