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We can live a few weeks without food, a few days without water and about only 2 minutes without breathing.  Life begins and ends with our first and last breath.  Why is breathing so important?  Because it is the key to the body's transformation of energy and without  beinag able to make energy, we die. 


But how do breathing and your weight  relate? Let’s be honest here, most people don’t enjoy looking at their excess belly fat (tummy, muffin top, paunch, etc.). Unfortunately, when it comes to losing fat, lots of people believe it only has to do with diet and exercise, but there’s way more to it than that. The reality is, is that most people are misinformed or unaware of the complicated yet balanced processes that our bodies need to go through in order to lose weight safely and effectively.

Let's return to breathing. It’s common knowledge that in order for humans to live, we inhale oxygen (O2) and exhale carbon dioxide (CO2). However, many people don’t realize that the carbon dioxide they’re breathing out is actually their excess fat. In fact, the study of nutritional biochemistry around weight loss has proven time and again that breathing is our body’s main source of burning fat. Don’t get me wrong, this doesn’t mean that you’re going to lose that tummy simply by exhaling. 


(Proceed if you love scientific detail on how your body works!)

Now let’s take a closer look at the composition of human fat. Like everything in this universe, human fat is made up of atoms; specifically, carbon, water and oxygen. The chemical formula for the average human fat molecule (series of atoms or bonds) is C55H104O6. It’s important to understand that each atom has its own weight (mass). Therefore, when we lose fat (weight) it is solely measured in kilograms (kgs) and not in calories or kilojoules. Despite these and other proven facts, many people continue to believe in the market-driven, misleading, calorie theory that body fat gained = calories in – calories out. That consuming less calories will lead to weight and fat loss. This is not always true.


Another common misconception about weight loss is that ‘lost’ fat is converted into heat and energy. However, this violates the law of conservation. This misconception, unfortunately, has survived for dozens of years due to many people continuing to believe in the ‘energy in/energy out’ mantra around weight loss and metabolism.     


Now let’s dive deeper into the function of breathing (inhaling and exhaling). Let’s begin with photosynthesis, the process where plants convert water, light and carbon dioxide into chemical energy that is stored in the form of glucose. When we consume plants, we consume glucose. When this happens, our bodies naturally transform the glucose into energy and any remaining glucose is stored in our bodies as fat. When we inhale, the oxygen we breath in fuses to the carbon that’s in the stored fat, and after numerous chemical reactions, we literally exhale the stored fat into the air in the form of carbon dioxide (CO2) and water (H2O). 


Let’s put this concept into perspective with the following example. Say you wanted to ‘lose’ 10 Kg (22 lbs.) of fat. Well, in order for your body to do so, your metabolism would require the inhalation of roughly 29 Kg (63 lbs.) of oxygen. Of the ‘lost’ 10 Kg (22 lbs.) of fat, 8.4 Kg (18.5 lbs.) would be exhaled as carbon dioxide through your lungs and the remaining 1.6 Kg (3.5 lbs.) would be excreted through bodily fluids such as urine, sweat, tears and water vapor in our breath.


What sparked my interest about the biochemistry of weight loss was a result of personal experience. I gained and lost 4 Kg (8 lbs.), most notably in my stomach, and wondered exactly how that weight disappeared. So I started conducting my own review of the scientific and nutritional biochemistry research and stumbled upon eye-opening findings about to how our human biochemistry and physiology really work and how many publicly available diet and weight loss programs are misleading, ineffective, and even dangerous. The more I researched about the technicalities of weight loss, the more I was convinced results were directly related to many, if not all, aspects of a healthy lifestyle. To that end, I found myself wanting to share this new knowledge with everyone. To share a novel approach in hopes that it would help motivate you  to think, move and breathe more in the same way that it motivated me.. 


I already mentioned, the biochemistry of our belly fat is comprised of tight bonds of carbon, hydrogen, and oxygen atoms. These bonds are broken in the presence of oxygen when we inhale. The breakdown rate of fat molecules is even greater during physical activity. When inhaling, oxygen fuses to our stored fat molecules, the water we drink, and the micronutrients that are in the foods we consume. This process is how our bodies produce ATP (adenosine triphosphate), a form of energy that all living organisms need to produce in order to do absolutely everything. Therefore, the more physically active we are, the more ATP we will produce, which leads to fat burning. 

Let’s take a closer look as to how the average fat molecule (C55H104O6) is broken down. Inhaled oxygen fuses to all the carbon atoms (C55) of a fat molecule forming numerous carbon dioxide (CO2) molecules that we exhale. Inhaled oxygen also fuses to all hydrogen atoms (H104) of a fat molecule forming molecules of water (H2O), which we exhale with our breath. Lastly, when inhaled oxygen meets the oxygen atoms (O6) of a fat molecule, the oxygen of the fat molecule is shared in a 2:1 ratio to form both carbon dioxide (CO2; exhaled) and water (H2O; exhaled or excreted) respectively. In other words, 4 oxygen atoms of a fat molecule are used to form carbon dioxide molecules that are exhaled and the other 2 oxygen atoms are used to form water molecules that are excreted through bodily fluids. Simply put, 84 percent of the atoms that make up the average fat molecule are exhaled as carbon dioxide, while the remaining 16 percent leave the body in the form of water through bodily fluids. This shows us how breathing has the greatest effect on weight loss.

So how exactly do we gain weight and lose it? We put on weight when excess protein and cabs that we have eaten are converted into triglycerides (a combination of fatty acids) and are then stored in lipid droplets inside fat cells. To lose weight, you need to break down those triglycerides to access their carbon so you can exhale them out of your body. The results in the example above, show that in order to completely breakdown 22 pounds (10 Kg) of human fat, we need to inhale 64 pounds (29 Kg) of oxygen (essentially burning roughly 94,000 calories). This reaction to this inhaling of oxygen then produces 62 pounds (28 kg) of CO2 and 24 pounds (11 Kg) of water. This allowed them to come up with the final figure of 84 percent of a fat molecule's atoms being exhaled as carbon dioxide, and the remaining 16 percent ending up as water.


Now let’s discuss carbs and proteins and their relationship to fat. Excess carbohydrates or protein in the diet is converted to triglycerides and stored in the lipid droplets found in adipocytes, cells that specialize in storing energy as fat. Excess dietary fat needs no conversion other than lipolysis, a process of breaking down fat in the presence of water. If we wish to lose weight while maintaining our muscle, biochemically speaking, we are attempting to metabolize the triglycerides stored in our adipocytes. The complete oxidation of a single triglyceride molecule involves many enzymes and biochemical steps, but the entire process can be summarized in the following example.


The complete breakdown and oxidation of 10 Kg of human fat requires 29 kg of inhaled oxygen, which will produce 28 Kg of carbon dioxide CO2 and 11 Kg of water H2O. This tells us the metabolic rate of fat, but remains silent about the proportions of the mass stored in those 10 Kg of fat that depart as carbon dioxide or water during weight loss.These results show that the lungs are the primary excretory organ for weight loss. The water formed will be excreted in the urine, sweat, breath, tears, or other bodily fluids.


Now let’s focus on the impact of exercise on weight loss (aka fat burning, metabolic rate). For comparison, 500 g of sugar (sucrose)(C12H22O11), made up form glucose and fructose, provides 8400 kJ (2000 kcal) and contains 210 g of carbon. Replacing one hour of rest with exercise raises the metabolic rate to seven times greater than being inactive (resting). Physical activity, such as jogging, removes an additional 39 g of carbon from the body, raising the total metabolic rate by about 20%, which means 240 g of carbon in fat is lost. For comparison, a single 100 g muffin represents about 20% of an average person’s total daily energy requirement. Physical activity as a weight loss strategy is, therefore, easily foiled by relatively small quantities of excess food.


Through extensive analysis and calculations, we have drawn the following conclusions about weight loss and metabolism: 

  • The lungs are the primary excretory organ for fat;

  • Weight loss requires unlocking carbon stored in fat cells, thus reinforcing that often heard refrain of “eat less, move more”.

  • A person’s metabolism is in constant communication with the body and brain for the purposes of keeping balance (homeostatic metabolic rate) between energy saved and energy expended.

  • At the mitochondrial level, depending on our habits (diet/lifestyle) the process by which our metabolism manufactures our energy (metabolic rate) could lead to health (homeostasis) or could lead to chronic disease (metabolic syndrome). 


Given the conclusions above, Boston Healthiest would love to see educational institutions and popular media include the most up to date science and thinking on what really influences unhealthy weight changes so that we can start to alleviate the widespread misconceptions that abound.


Boston Healthiest uses nutritional biochemistry, which is the science that helps us best understand how to develop a personalized lifestyle plan based on your unique metabolism and personal goals.  You see, our metabolism doesn't know how to count calories, inches or weight. Our metabolism functions best when our oxygenation, hydration and micronutrients (from food we consume) are in perfect equilibrium.  Small, but constant damage to that equilibrium is what eventually leads to disease. 

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