Most people think we lose weight by converting body fat into energy, creating heat, and by sweating off the pounds during vigorous workouts, but the way the body actually rids itself of fat may surprise you.
In a study published in the British Medical Journal, researchers investigated where the fat goes when one loses weight and, as it turns out, we don’t burn it off—we breathe it out!
The study found that fats are broken down into CO2 (carbon dioxide), and we literally breathe it out.
For example, 22 pounds of broken-down fat converts into 18.5 pounds of carbon dioxide and 3.5 pounds of water. We remove this water through sweat, tears, or urine and, quite naturally, breathe off the CO2.
So, it’s actually accurate to say that the fat you burned and weight you lost actually vanished into thin air!
How it Works
When we gain weight, the extra calories we ingest from overeating are converted into triglyceride fats and stored in fatty lipid droplets within your fat cells. Triglycerides are made up of carbon, hydrogen, and oxygen. In order to lose the weight and burn the fat, we need the energy to break the triglycerides down to release the carbon. The result of this breakdown is carbon dioxide—which we breathe out—and water.
For example, to break down 22 pounds of fat, we need to inhale 64 pounds of oxygen and burn some 94,000 calories. This reaction produces 62 pounds of CO2 body mass that are breathed away and 24 pounds of water.
On average, we breathe 12 times a minute when we are at rest. We breathe around 17,000 breaths per day, during which we breathe off about 10 milligrams of fat with each breath. That is not a lot, but it does add up.
For example, a standard herbal capsule contains roughly 500 milligrams of an herb, so for you to burn the weight of one herbal capsule, you need to breathe 50 times or for about 3 minutes. (1)
During exercise, the efficiency of breathing off the fat increases metabolic activity seven-fold—which increases the CO2 breathed away as fat by 20%.
If you engage in 1 hour of exercise, you will breathe away 240 grams of fat (carbon) compared to 203 grams if you were to remain sedentary. (1)
Eating a muffin, however, can add about 100 grams of carbon-based body mass, which makes up about 20% of the normal caloric intake. Adding a 1-hour workout to your day would not burn off the potential fat stored from the muffin, making exercise an inefficient means of burning fat.
The conclusion of this study suggests that weight loss is based on two factors: eating less and moving the body more. (1)
But wait… What if we breathed more efficiently and used all five lobes of our lungs, instead of just the upper two?!
Proper Breathing During Exercise Pays Off
The average amount of air that is inspired or expired during in one breath is about 500 milliliters of air. This is called tidal volume. The inspiratory reserve volume, which is the extra amount of air that could be inhaled if the breathing was maximal, is about 3000 milliliters. Adding this to the tidal volume (500 milliliters) equals an inspiratory capacity of 3500 milliliters, which is at least six times the amount most people inhale. (2) Breathing to one’s full respiratory capacity (3500 milliliters) could potentially support the exhalation of CO2 or fat-burning six-fold.
Theoretically, this could boost the amount of fat loss from the weight of one herbal capsule to six in just 3 minutes—that is more than the weight of five bottles of herbal capsules in a day.
If you exercise and eat right, it really does start to add up!
To access full respiratory capacity (all five lobes of the lungs), breathing must be maximally efficient, and this can only happen when we use the body’s primary breathing apparatus—the nose.
As infants, humans are considered obligate nose breathers and, thus, are obligated to breathe through the nose rather than the mouth. (4) Nose breathing drives air through the turbinates in the nose, which act like small turbines to drive a smaller stream of air into the lower lobes of the lungs. The lower lobes of the lungs are where the predominant amount of blood rich alveoli reside for oxygen and CO2 exchange. (2,4,5)
Learning how to exercise while breathing through the nose takes about three weeks of nose breathing training. Once you establish respiratory efficiency through nose breathing, the benefits are truly striking.
Many years ago, for my first book, Body, Mind, and Sport, we conducted a study published in the International Journal of Neuroscience on nose breathing versus mouth breathing. These were the benefits we found: (4,5)
- HEART RATE: There was no significant difference in heart rate between nose and mouth breathing exercise. Previous studies suggested that heart rates should go up during nose breathing, even if the workloads were the same. In our studies, they stayed the same, suggesting an ease and comfort during exertion using nose breathing that was unprecedented.
- BREATH RATE: Breath rates were consistently lower during nose breathing exercise (nasal breathing exercise) in both studies we performed. For example, if you look at my case study, you’ll find that at the maximum exertion of 200 watts of resistance on the stationary bike, the rate of breath for the nose breathing technique was a mere 14 breaths per minute compared to the whopping 48 breaths per minute while mouth breathing. This suggests that nose breathing was more efficient and all five lobes of the lungs were used. Read the study here.
- PERCEIVED EXERTION: In our studies, perceived exertion was significantly lower with the nose breathing technique. To measure this, we assigned a scale of 1-10 (10 being the most stressful) on the stationary bike at maximum exertion (200 watts). During mouth breathing, the perceived exertion topped the scale at a 10. During nose breathing? It was a comfortable 4. When using all five lobes of the lungs, the efficiency in breathing out CO2 or fat is maximized. Huffing and puffing during a workout are due to inefficient breathing and poor CO2 removal.
- NERVOUS SYSTEM: Parasympathetic nervous system activation increased significantly during nose breathing as compared to mouth breathing. The receptors for the parasympathetic nervous system are found concentrated in the lower lobes of the lungs. This suggests that nose breathing more efficiently accesses the lower lobes where most of the fat-burning or CO2 exchange takes place. To make this determination, we measured the respiratory sinus arrhythmia (RSA), or the variability of the heart rate in relation to respiration. The more variable the heart rhythm, the more relaxed the individual or the more active the parasympathetic tone. At the same time, the tone of the sympathetic nervous system – the system responsible for the “fight or flight” mechanism – was lowered with nose breathing as compared to mouth breathing. This suggests that the individual may have experienced a “zone state,” as both nervous systems were functioning symbiotically to induce calm and focus during exercise. This is what athletes describe when they state, “My best race was my easiest race experience.”
- BRAIN WAVES: Though studies typically suggest that the brain becomes more incoherent during periods of stress and exertion, our studies show the opposite: brain wave measurements showed higher coherence using the nose breathing technique. This suggests that the entire brain pattern was more relaxed while engaged in nose breathing exercise compared to mouth breathing.
- ALPHA PATTERNS: Alpha brain wave patterns—the brain waves associated with deep relaxation and meditative consciousness—were significantly higher during nose breathing in both studies. In the first case study, the brain produced an unprecedented 15-second alpha wave burst. I signaled when I thought I was in “the zone,” which ended up correlating with when the brain went into the alpha burst. This finding was replicated in the follow-up study. Until these studies, alpha brain wave activity had not been documented during exercise at all!
- ENDURANCE: Endurance was significantly higher in both studies using the nose breathing technique as compared to mouth breathing. When CO2 builds up due to inefficient breathing, both endurance and recovery time will be compromised.