THE SCIENCE BEHIND WEIGHT LOSS

Updated: Apr 10

Weight management is hard. Two thirds of people are overweight or obese, and although fat shaming is despicable, talking about the health risks associated with carrying excess body fat shouldn’t ever be off limits, or taboo. I truly believe that knowledge is power, and anyone looking for an optimal body weight should understand the nuts and bolts of the process. Although I don’t pretend to be a weight loss expert, I do believe everyone looking for optimal health and body weight should be made aware of the building blocks of calorie balance.

Weight management can be made super simple and we can have great control over many of the variables that contribute. So let’s break it down and build it back up! It all starts with energy balance. Body weight will change according to a few very simple equations:


ENERGY BALANCE = ENERGY IN MINUS ENERGY OUT, and since energy from food is measured in calories:


CALORIE BALANCE = CALORIES IN - CALORIES OUT, so we can conclude that:


CALORIE DEFICIT = WEIGHT LOSS

CALORIE EXCESS = WEIGHT GAIN


Since we measure energy from food in calories, we could also rephrase by saying “calories in versus calories out”. I’m confident you’ve heard this cliché before, and for the most part, it’s true. The ”calories in” side of things includes the foods we put in our bodies and is the main driver of energy balance. This is, for the most part, completely within our control, meaning that we “control” what we eat (I’ll discuss other influences a bit later). The ”calories out” side is a little more complicated and must be broken down into the sum of its parts.

Calories In

This one isn't too complicated. Calories come from food, and excess calories are stored in glycogen or fat. Specific quantities of food contain specific quantities of energy, or calories. One gram of protein and 1 gram of carbohydrates both contain 4 calories each. One gram of fat contains 9 calories. The oversimplified way of seeing food as simply the sum of it's macronutrients is called "nutritionism", and can be quite harmful. By seeing food only as macronutrients instead of whole food, we rely on grams of carbs, fats or protein to guide our food choices. Let me explain. If I were to tell you to eat 100 grams of a food that has 15 grams of fat, 20 grams of carbs and 2 grams of protein, totaling almost 160 calories, you might think it's unhealthy. That food is an avocado, a superfood. Now here's where relying only on macros is dangerous. 80% of carbs in avocados are indigestible fibers that will provide zero calories. The carbs contained in avocado are healthy complex carbs, and only 0.6 grams are sugar. The fats are mostly unsaturated, meaning healthy and protective. They have been found to protect against heart disease, inflammation, obesity, cancer and diabetes. 75% of the avocado is actually water, and when combined with fiber, makes you feel fuller for longer, and might help curb your calorie intake later that day. So making food choices simply by relying on macro splits is an unreliable way to achieve optimal health. By basing health measures on macros alone, we are ignoring vitamins, fibers, types of fat, polyphenols and other phytonutrients that are only found in plants and that contribute greatly to the health promoting effects of a particular food. Bottom line: make sure your "calories in" are good calories and don’t rely solely on macros when making food choices. Check out my previous post: "A calorie isn't always a calorie", if you'd like more details on this important fact that many people leave out. Look at the big picture when making food choices, since macronutrient content alone is an oversimplification that may lead people in the wrong direction. I'll come back to this subject below for more tips on how we can have more control on the "calories in" part of the equation.


Calories Out

The "calories out" side of the equation has 4 major components. We can have some control over all 4 of them, and use this to our advantage when trying to achieve a healthy body weight. Let's start by listing them, then I'll break down in more detail how we can use these to our weight management advantage.

  1. Basal metabolic rate, or BMR

  2. Food thermogenesis (the energy required to digest food)

  3. Non-exercise activity thermogenesis, or NEAT, also called incidental exercise

  4. Exercise thermogenesis


Basal metabolic rate

BMR is the energy required to simply be alive. Every heartbeat or breathe we take requires energy, and many biochemical processes going on without our knowledge use calories for fuel. Just existing consumes energy, and our BMR contributes to up to 60% of the calories we burn every day. Many factors contributing to BMR are out of our control, like our sex, age, height, ethnicity and genetics, but there are some that we can control, and I'll come back to those in a minute. If you'd like to calculate your BMR, the Harris-Benedict formula is a good starting point and you can easily find online calculators to help you determine if you're eating in a calorie deficit or excess. Although BMR does slow down with age and with weight loss, there are a few things you can do to increase it in order to burn more calories every day by just staying alive! I’ll get back to these soon!


Food thermogenesis

This is the energy that our body uses to digest and process food in order to use and store energy. The quantity and the types of food we eat will affect this differently. Protein requires more calories to digest, when compared to carbs which comes in second. Fat requires the least amount of energy to process. This can partly explain why people who want to lose weight are told to increase their intake of protein, which requires more energy to digest and process, and to decrease their consumption of fat, since fat has the most calories per gram, and requires the least calories to digest and process. Ultra-processed foods require almost no energy to break down, and high fiber and protein foods require the most, again emphasizing that whole plant foods are better suited for weight management compared to processed or animal foods.


Calories burned by moving your body

These calories encompass points 3 and 4 of the "calories out" equation. NEAT refers to "incidental exercise", where you're moving your body but not intentionally exercising. Think of walking from the parking lot to the store, vacuuming, washing the dishes, etc. These tidbits of calories burned here and there can accumulate quickly and do contribute significantly to overall energy expenditure. I'll come back to this factor later when explaining how we can use NEAT energy expenditure to our advantage. Studies have shown that NEAT calorie expenditure can vary from person to person by up to 2000 calories in a single day, depending on how much we move. Compare a desk job to a landscaping one for example.


Exercise as a means of burning calories is the final and most obvious contributor to the "calories out" equation. Whether it's LISS (low-intensity steady state) cardio, HIIT (high intensity interval training) or resistance training, they all contribute to weight management, and are completely within our control. I'll go over in more detail the types of exercise that work best for weight management in a future blog post, but for now simply remember that surprisingly, exercise isn't the most important factor in determining body weight, nutrition is.


So now that you know all of the factors that contribute to energy balance, let's review them and see how we can control these variables in order to make them work to our advantage. "Calories in" is the easy one, and the foods we eat are the sole contributors to this part of the equation. The "calories out" part is determined by our BMR (basal metabolic rate), our food thermogenesis (the energy required to break down and absorb food) and by the way we move our bodies, either through "incidental exercise" (or NEAT), or through voluntary exercise. Let's break them down and see how we can use them for weight loss.

How we can control "calories in"

The "calories in" part is the most complex one to manage, and is easier said than done. People seem to have no issues differentiating foods that are healthy from those that aren't. We all realize that ice cream isn't a health food, but resisting temptation can still be an issue. Eating behaviors are influenced by many factors that can contribute to the over-consumption of calories, including emotions, distractions, and timing of meals. Here are a few quick tips that can help you with the "calories in" part of our energy balance equation.

  • focus on whole unprocessed foods, since they tend to keep you fuller for longer. They also have lower calorie densities, meaning that you can actually eat more food for less calories. Some foods are simply impossible to overeat, like berries and vegetables for example. Processed foods tend to leave your body overfed, but under-nourished, and promote excessive calorie consumption.

  • never go grocery shopping on a empty stomach. The dopamine reward centers of our primal brains have been proven to light up on MRI studies by simply seeing pictures of foods we like. It's very easy to convince yourself to purchase unhealthy food when you're hungry. Stick to the outside perimeter of the store, where fresh produce and healthier options are usually kept.

  • eat slowly. Studies show that mindful eating, putting our utensils down between bites, and drinking water with meals can slow down our eating enough to give our fullness signals time to reach the brain.

  • eat with family. Studies show that eating with family at the dinner table helps reinforce healthier eating behaviors. Turn off the television, since distractions like this have been shown to increase calorie consumption.

  • pre-load with negative calories. Eating low calorie density foods first, like a soup or salad, has been shown to decrease overall calorie consumption. Drinking water 30-60 minutes prior to a meal can also help curb your appetite.

  • choose smaller plates, smaller spoons or smaller bowls. This purposely tricks our primal brains into thinking that we've eaten more and helps decrease excessive calorie consumption.


How to control "calories out"

Controlling BMR

If you’ve been paying attention up til now, then you understand that many uncontrollable factors will determine our BMR, but it’s important to recognize that we do control some of them. We can control basal metabolism by increasing our muscle mass. Muscle requires energy, and so a body with more muscle will burn more calories, even at rest. Resistance exercises, instead of cardio, will help build more muscle and burn more calories, even at rest. Something as simple as drinking cold water can also temporarily boost metabolism, since the body has to bring the water to body temperature for proper use, a process called water thermogenesis. Regularly integrating foods proven to increase metabolism could also end up burning extra fat. Certain foods like spices, including cayenne, ginger, turmeric, etc., can trigger increased noradrenaline release and make your body burn more calories at rest.

Controlling food thermogenesis

Now that we know that protein will require more calories to digest and process than fat or carbohydrates, increasing your protein intake will burn more calories. The recommended daily intake of protein is about 0.8 grams per kilogram of lean body weight, so aim for something close to this amount. Athletes should increase to 1.2-1.4 grams per kilogram and those looking to build muscle could increase to 1.6 grams per kilogram. So if you want to profit from this hack, consider logging your protein intake to see where you stand, and then adjust if needed.

Controlling your NEAT

NEAT represents the “incidental” or involuntary exercise you do everyday while doing house chores, walking to your car, vacuuming your home or going shopping. There are infinite and clever ways to increase your NEAT daily, and small contributions will add up. If you’re talking on the phone, consider walking around the house, or up and down the stairs. When you go at the store, park farther away from the door so you take more steps. Consider getting a step counter, measure your average number of steps and then focus on slowly increasing. Get a standing desk at work, or walk over to a colleague instead of sending them a text or email. You probably get the point by now, so think up new and clever ways to increase your NEAT calorie expenditure, it adds up to considerable amounts over time.

Exercise thermogenesis

No big revelation here, exercising burns calories. But if you’re thinking cardio, you should think again. When comparing LISS (low intensity steady state) exercise to HIIT (high intensity interval training), studies seem to show conflicting evidence. Most studies seem to show that HIIT is more efficient at burning calories than LISS, and helps boost metabolism for longer after the workout is done. That being said, HIIT is also harder on the body, and less enjoyable for many. On the other hand, LISS is less painful, can be enjoyed more frequently, but requires more time. My scientific conclusion is to do the exercises that you will do long term. Personally, I do cardio in the form of spin bike, rowing and running 2-3 times per week, and also do HIIT training 1-2 times per week. Let’s not forget resistance and weight training. Although these workouts might not burn as many calories right then and there, they do increase muscle mass, which increases BMR, as stated previously. This simply reiterates that the best workout plan is the one you’ll do more often. If you’re extra motivated, then a great workout plan would include a mix of LISS, HIIT and resistance exercises.

My Weight Loss Prescription

When people think of weight loss, they unfortunately think of restrictive diets and pounding the treadmill. Fortunately, that’s not the only way to achieve a healthy body weight. We control many factors that will impact our weight and breaking them down into their smaller parts makes them easier to digest. Let me remind you one last time of the most important equation for weight loss.

CALORIE BALANCE = CALORIES IN - CALORIES OUT

“Calories in” can be better managed by eating low calorie density foods, high fiber foods, and foods that contain water, creating bulk without calories. Whole plant foods tick all of these boxes. Eating salads, fruits or even just drinking water 30-60 minutes before a meal can help curb your appetite and help decrease total calorie intake. I detail a whole bunch of weight loss tips directly on my website in the section “For weight loss”. Go check out plantbaseddrjules.com

“Calories out“ can be increased by increasing your metabolism. Building muscle, drinking more water and eating more spices can do this for you. Energy balance can also be affected by eating more plant protein and fibre rich foods, like beans, lentils, chickpeas and tofu. These foods require more energy to digest and than refined “Franken-foods”. Think of clever ways to increase NEAT and when planning your next workout, try to increase resistance and weight training in order to build muscle, and mix it up by trying to include both LISS and HIIT exercises.

I hope you’ve enjoyed the science of energy balance! Check out my website plantbaseddrjules.com for tons of tips and tricks to include more plants and whole foods in your diet and have a look at the “For Weight Loss” section for tons of evidence based weight loss recommendations.


Check out my website plantbaseddrjules.com and look for the “How To” section in the menu. There, you’ll find tips and tricks that helped me on my journey towards a plant-predominant diet. Everything there is completely free, no catches! If you're looking for quick, easy and healthy plant-based recipes, check out plantbaseddrjules.com and download my free recipe eBook!


Look for me on the socials, @plantbased_dr_jules on Instagram and go like my Facebook Page, Plant-based Dr. Jules. If you’re looking for some fitness motivation and are curious to see what a plant-based athlete can accomplish, follow me, @maritimeninja, on my fitness account on Instagram or check out my fitness group on Facebook, called Maritime Ninja Warrior. Me and my wife Melissa have recently qualified for the Las Vegas Ninja Warrior World Championships that will be held in July 2022, and you can follow our journey on IG!


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Plant-Based Dr. Jules 💚🌱

plantbaseddrjules.com

@plantbased_dr_jules

@maritimeninja



Take care of yourselves and others! Plant-based Dr Jules 🌱💚



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