Keto Means
Photo by Anna Tarazevich Pexels Logo Photo: Anna Tarazevich

Does fat leave the body through poop?

To keep it simple, as your body burns up excess fat to create fuel after joining a weight loss program, you then breathe it out as carbon dioxide or expel it through your sweat, urine, tears, and feces. Fat is basically stored energy. And your body uses energy in more ways than you'd think.

callaslimspa.com - How Does Fat Leave the Body - Calla Slimspa
What shrinks fat cells?
What shrinks fat cells?

With a sufficient calorie deficit and proper exercise regimen, fat cells shrink over time as their contents are used for energy, leading to...

Read More »
Last updated Jun 26, 2021
What is the lowest carb rice?
What is the lowest carb rice?

Compared with other types of rice, wild rice is significantly lower in carbs, with 32 grams of net carbs in each 1 cup (164 gram) serving of cooked...

Read More »
Last updated Aug 17, 2019

[updated September 2019]

If you’ve recently joined a weight loss program to help you lose weight, you may be wondering how fat leaves the body once you start losing weight. Weight loss is achieved through a combination of a healthy exercise and a healthy diet plan that focuses on lean protein, healthy fats, and carbohydrates from fruits and vegetables. This combination aids the body in burning stored fat for fuel and energy and preventing the body from storing excess fat that you continue to consume.

But what happens to body fat when you shed pounds – do you sweat it out, pee it out or breathe it out?



How Fat Leaves the Body When You Lose Weight

Watch this video for more information about what happens to the fat that is burned off when you lose weight. To keep it simple, as your body burns up excess fat to create fuel after joining a weight loss program, you then breathe it out as carbon dioxide or expel it through your sweat, urine, tears, and feces. Fat is basically stored energy. And your body uses energy in more ways than you’d think. When you are resting your heart needs the energy to pump your lungs to breathe and your brain to think. This is your basal metabolism. When you’re active your muscles need energy. This means anything from getting up from a chair to running marathon. When you’re eating your digestive system needs the energy to break down and store food. When you diet, you take in fewer calories than your body needs. Due to the deficit, your body turns to fat reserves for energy. During the fat burning process, the body converts fat into usable energy for your muscles and other tissues causing the fat cell to shrink. When you exercise, your muscles first burn through stored glycogen for energy. Typically, after 30-60 minutes of aerobic exercise, your body has burned through the stored glycogen and starts burning mainly fat. Most of us really don’t think about where fat goes when we lose it. In all honesty, we’re just happy that the scale says it’s gone and our clothes fit better. But the fat doesn’t magically disappear when your body starts to burn fat. Research shows that 84% of fat loss is exhaled as carbon dioxide. The remaining 16% of fat is excreted as water. During the conversion of energy, carbon dioxide, and water are byproducts of waste. They are excreted via urine, perspiration, and exhalation. Interestingly, research reveals the lungs as the primary organ used to remove from the body.

Key to Losing Fat

According to physicist Ruben Meerman, who has done extensive research in fat metabolism that was published in the British Medical Journal in 2014, calculations show that the lungs are the primary excretory organ for fat. Losing weight requires unlocking the carbon stored in fat cells thus reinforcing the often-heard refrain of “eat less, move more.”

About the Author – Suzanne Gil, M.D.

Dr. Suzanne Gil obtained advanced training in bariatrics (weight loss medicine) and opened Calla Slimspa Medical Weight Loss Center located in Orlando, FL in 2008 when the need for weight-related assistance became a huge priority. She is a member of the American Society of Bariatric Physicians (ASBP) and dedicates 100% of her professional time to helping as many people as possible achieve their weight loss goals and improve their health. She completed her residency at Orlando Regional Medical Center and is a Board Certified Pediatrician.

How long do you have to be in ketosis to burn fat?
How long do you have to be in ketosis to burn fat?

Fat adaptation may start any time between 4 and 12 weeks after you enter ketosis, depending on the individual and how strictly you adhere to the...

Read More »
Last updated Jul 28, 2020
Do eggs clear your bowels?
Do eggs clear your bowels?

According to Dr. Lee, “For someone dealing with predominant diarrhea (the fast transit type where they have loose frequent bowel movements), eggs...

Read More »
Last updated Dec 10, 2019

Where do fat cells go when you lose weight?

As your body metabolizes fat, fatty acid molecules are released into the bloodstream and travel to the heart, lungs, and muscles, which break them apart and use the energy stored in their chemical bonds. The pounds you shed are essentially the byproducts of that process.

technologyreview.com - When you lose weight, where does it go? - MIT Technology Review

We use energy all the time, whether we’re running, eating, or sleeping. The energy we use at rest—to pump blood, digest food, regulate temperature, repair cells, breathe, or think—is our baseline metabolism, the minimum energy required to maintain the body’s basic biological functions. So if we’re carrying extra weight, it’s because we’re taking in more energy than we’re using. (The much-cursed thickening around our bellies is a combination of accumulated deep visceral fat and more shallow subcutaneous fat.) When we expend energy during intense bouts of exercise and other physical activity, the glycogen in our muscles is used first. The liver releases glycogen to help with muscle activity and to regulate blood glucose levels. After about 30 to 60 minutes of aerobic exercise, the body begins to burn fat. If we take in less energy than the body needs overall to maintain itself—as when dieting—then the body turns more often to fat reserves for energy. As your body metabolizes fat, fatty acid molecules are released into the bloodstream and travel to the heart, lungs, and muscles, which break them apart and use the energy stored in their chemical bonds. The pounds you shed are essentially the byproducts of that process. They are excreted in the form of water—when you sweat and pee—and carbon dioxide, when you exhale. In fact, the lungs are the primary excretory organ for fat. The body uses energy to carry out the usual basic processes at rest—again, your baseline metabolism—and for the physical activity you do on top of that, which is considered your active metabolism.

What is it called when you eat everything but red meat?
What is it called when you eat everything but red meat?

Alpha-gal syndrome is a type of food allergy. It makes people allergic to red meat and other products made from mammals. Nov 15, 2022

Read More »
Last updated Feb 26, 2022
Which fruit is best for liver?
Which fruit is best for liver?

Fill your fruit basket with apples, grapes and citrus fruits like oranges and lemons, which are proven to be liver-friendly fruits. Consume grapes...

Read More »
Last updated Mar 17, 2022
Why is cottage cheese so high in carbs?
Why is cottage cheese so high in carbs?

The carb content of cottage cheese is around 3%. It consists of lactose, a milk sugar to which some people are intolerant. When eating high amounts...

Read More »
Last updated Dec 8, 2021
How heavy was Khloe at her heaviest?
How heavy was Khloe at her heaviest?

Khloe weighed 163 pounds (about 74 kg). But after changing her diet and workout, she lost 40 pounds and now weighs 123 pounds (55 kg). Will her...

Read More »
Last updated Apr 1, 2020