Breathe to Lose Weight?

Scientific evidence that shows where lost fat actually goes.
Written by Jenn Giamo

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“Burn off those calories!”
“Sweat it out!”
“Melt your fat away.”

These phrases are commonly heard by your favorite fitness instructor in your Saturday morning fat-burning class. If you’re a fitness enthusiast, you may have even heard (incorrectly) that you can turn your fat into muscle. This is scientifically impossible. Fat and muscle are separate entities and cannot be converted from one to the other. You also may have been told to drink lots of water to ‘flush out fat’ or eat fiber-rich foods to excrete it. Some even believe that when we lose fat, it is converted to energy. If you remember High School chemistry and the Law of the Conservation of Matter: energy cannot be created or destroyed. So that theory is out. While working out, replenishing fluids and eating a proper diet are all great ways to help you lose weight, these misconceptions can lead to confusion.

We know that our bodies need a certain amount of energy to function efficiently. We also know that we typically get that energy from the food we eat. When you consume more than you expend, you will gain weight. With me so far, right? This is all pretty common knowledge, but it starts to get tricky when we talk about the storage form of fat in the cells. When you eat more than you use, your body will store that energy as triglycerides in the cells along with excess protein and carbohydrates. On the flip side, when you consume less, your body begins to tap into these stores for fuel. This is when triglycerides are released into the bloodstream and breakdown into fatty acids. Without getting too involved in the biochemical processes here, those fatty acids get broken down even further to produce energy, and your body is left with a small amount of remaining water and lots of carbon dioxide.

In spite of our obsession with weight loss, trendy diets and our desire to see a lower number on the scale, many of us are unaware of just what happens when we “lose” a pound of fat. In a 2014 study reported in the British Medical Journal (BJM), researchers found that the proportion of fat mass that ends up as carbon dioxide accounted for 84% and compared to 16% as water. That’s correct - we BREATHE out most of our fat! The small percentage that is lost as water is likely through sweat and urine. To put this in perspective: if you lose 10 pounds, 8.4 are lost through respiration and 1.6 through bodily fluids.

If you really want to know the numbers, a CNN report provides the following information:

“According to the latest government figures, Americans consume 125 ounces of food and beverages every day. Of that, about 15 ounces is solid macronutrients, 17 grams (0.6 ounces) is fiber and the remaining 3.11 kg (110 ounces) is water. What's not reported is that we inhale more than 660 grams (23 ounces) worth of oxygen, too, and this figure is equally important for your waistline.”

So if you’re putting 125 ounces of food and water into your body, plus the additional 23 ounces that you’re inhaling, you’ll need to create a balance so that you don’t gain weight. So how can we do that with little effort? For starters, get adequate sleep. We exhale approximately a quarter of this during the night. Next, move your body as much as possible - brisk walking should make up for the rest. You may be wondering, “why can’t I just sit and take lots of deep breaths in and out?” Well, besides passing out, the mere process of exhalation isn’t going to tap into your fat stores. You need to actively move your muscles in order to reap the benefits. Intense workouts are a great way to increase carbon dioxide output, but not always necessary. It really doesn’t take much more than folding some laundry. And with all the exercising you’ll be doing now to lose fat - you’ll probably have a lot of laundry.

Amanda Gay