Photo by Jonathan Borba on Unsplash
One of the biggest misconceptions about fat loss is that fat becomes energy. However, that’s not– strictly speaking– true. Fortunately, a better understanding of the physiology of fat can be useful.
First, let’s understand how the body metabolizes fat for energy. When you create a calorie deficit through diet and exercise, your body taps into its fat stores for fuel. Fat molecules are broken down into smaller components called fatty acids and glycerol, which can then be used as energy by your cells to maintain their functions. And we use energy all the time, including when we are at rest—to pump blood, digest food, regulate temperature, repair cells, breathe, or think. This is our baseline metabolism, the minimum energy required to maintain the body’s basic biological functions.
Believe it or not, the majority of fat that you burn is exhaled from your body in the form of carbon dioxide. When fat molecules are metabolized, they combine with oxygen to produce carbon dioxide (CO2) and water (H2O). The water is then excreted through urine, sweat, and other bodily fluids, while the carbon dioxide is expelled when you exhale.
Yep, the lungs are the primary excretory organ for fat!
Each time you take a breath, you’re exhaling carbon dioxide generated from the metabolism of fat. In fact, research suggests that about 80% of fat is lost through exhalation, making breathing an essential aspect of fat loss.
While exhaling is the primary way fat leaves the body, a portion is also eliminated through sweat and urine. When fat is metabolized, the water produced is excreted through these bodily fluids, contributing to overall fluid balance and waste removal. Any weight loss from sweating or urine, though, is your “water weight,” which can fluctuate with dehydration. Bodybuilders, models, and actors practice dehydrating themselves before a shirtless showcase, but it is not a recommended way to lose weight.
To recap: energy is not created and mass isn’t destroyed, rather everything becomes something else.
Now, while fat isn’t directly turned into energy, your muscles do play a crucial role in fat metabolism. As you engage in physical activity, your muscles require energy to fuel their contractions. Fat molecules stored within muscle cells are broken down and used as a source of fuel, further contributing to fat loss, usually after 30-60 minutes of exercise. Furthermore, increasing muscle mass can help you burn more calories, because muscles require more energy to build and maintain than fat does. This can boost your baseline metabolism– that is, someone is more muscle mass will burn more calories while sleeping than someone with less muscle mass.
Now, as we’ve discussed before, it’s important to note that the rate and efficiency of fat loss can vary from person to person due to factors such as genetics, metabolism, hormones, age, and overall health. While some individuals may experience rapid fat loss, others may progress more gradually. Don’t get wrapped up in some kind of “normal” weight loss progression or expectation. Consistency with healthy habits and patience are key to achieving sustainable results.
As you embark on your weight loss journey, take a moment to celebrate the incredible feat of fat loss. With each breath you take and drop of sweat you shed, you’re making tangible progress toward your health and wellness goals. Remember to consider what fuel you’re consuming and how much, since you’ll eventually be breathing it away. You’re exhaling fat molecules with each breath right now!
Fat loss is a remarkable process that involves the intricate interplay of metabolism, respiration, and physical activity. When we gain a deeper appreciation for your body’s capacity for transformation, we can remain positive and proactive. If you’re ready to learn more about your body and what you can do, schedule a free 15-minute phone call today!
