When we lose weight, where does it go?

  • Written by Ruben Meerman, Assistant scientist, UNSW

The world is obsessed with fad diets and weight loss, yet few of us know how a kilogram of fat actually vanishes off the scales.

Even the 150 doctors, dietitians and personal trainers we surveyed shared this surprising gap in their health literacy. The most common misconception by far, was that fat is converted to energy. The problem with this theory is that it violates the law of conservation of matter, which all chemical reactions obey.

Some respondents thought fat turns into muscle, which is impossible, and others assumed it escapes via the colon. Only three of our respondents gave the right answer, which means 98% of the health professionals in our survey could not explain how weight loss works.

So if not energy, muscles or the loo, where does fat go?

Read more: Food v exercise: What makes the biggest difference in weight loss?

The enlightening facts about fat metabolism

The correct answer is that fat is converted to carbon dioxide and water. You exhale the carbon dioxide and the water mixes into your circulation until it’s lost as urine or sweat.

If you lose 10kg of fat, precisely 8.4kg comes out through your lungs and the remaining 1.6kg turns into water. In other words, nearly all the weight we lose is exhaled.

This surprises just about everyone, but actually, almost everything we eat comes back out via the lungs. Every carbohydrate you digest and nearly all the fats are converted to carbon dioxide and water. The same goes for alcohol.

Protein shares the same fate, except for the small part that turns into urea and other solids, which you excrete as urine.

The only thing in food that makes it to your colon undigested and intact is dietary fibre (think corn). Everything else you swallow is absorbed into your bloodstream and organs and, after that, it’s not going anywhere until you’ve vaporised it.

Kilograms in versus kilograms out

We all learn that “energy in equals energy out” in high school. But energy is a notoriously confusing concept, even among health professionals and scientists who study obesity.

The reason we gain or lose weight is much less mysterious if we keep track of all the kilograms, too, not just those enigmatic kilojoules or calories.

According to the latest government figures, Australians consume 3.5kg of food and beverages every day. Of that, 415 grams is solid macronutrients, 23 grams is fibre and the remaining 3kg is water.

What’s not reported is that we inhale more than 600 grams worth of oxygen, too, and this figure is equally important for your waistline.

When we lose weight, where does it go? Walking increases our resting metabolic rate by 300%. from www.shutterstock.com

Read more: Why we regain weight after drastic dieting

If you put 3.5kg of food and water into your body, plus 600 grams of oxygen, then 4.1kg of stuff needs to come back out, or you’ll gain weight. If you’re hoping to shed some weight, more than 4.1kg will have to go. So how do you make this happen?

The 415 grams of carbohydrates, fats, protein and alcohol most Australians eat every day will produce exactly 740 grams of carbon dioxide plus 280 grams of water (about one cup) and about 35 grams of urea and other solids excreted as urine.

An average 75kg person’s resting metabolic rate (the rate at which the body uses energy when the person isn’t moving) produces about 590 grams of carbon dioxide per day. No pill or potion you can buy will increase that figure, despite the bold claims you might have heard.

Read more: Five supplements that claim to speed up weight loss – and what the science says

The good news is that you exhale 200 grams of carbon dioxide while you’re fast asleep every night, so you’ve already breathed out a quarter of your daily target before you even step out of bed.

When we lose weight, where does it go? The metabolic fate of an average Australian’s daily intake of food, water and oxygen (Nutrient intake data: Australian Bureau of Statistics, Australian Health Survey: Nutrition First Results - Foods and Nutrients)

Eat less, exhale more

So if fat turns into carbon dioxide, could simply breathing more make you lose weight? Unfortunately not. Huffing and puffing more than you need to is called hyperventilation and will only make you dizzy, or possibly faint. The only way you can consciously increase the amount of carbon dioxide your body is producing is by moving your muscles.

But here’s some more good news. Simply standing up and getting dressed more than doubles your metabolic rate. In other words, if you simply tried on all your outfits for 24 hours, you’d exhale more than 1,200 grams of carbon dioxide.

More realistically, going for a walk triples your metabolic rate, and so will cooking, vacuuming and sweeping.

Metabolising 100 grams of fat consumes 290 grams of oxygen and produces 280 grams of carbon dioxide plus 110 grams of water. The food you eat can’t change these figures.

Therefore, to lose 100 grams of fat, you have to exhale 280 grams of carbon dioxide on top of what you’ll produce by vaporising all your food, no matter what it is.

Any diet that supplies less “fuel” than you burn will do the trick, but with so many misconceptions about how weight loss works, few of us know why.

Authors: Ruben Meerman, Assistant scientist, UNSW

Read more http://theconversation.com/when-we-lose-weight-where-does-it-go-91594

Australia Today

Dry Carpet Cleaning Vs Steam Carpet Cleaning: Which one to Choose?

News Company

A clean carpet not only improve your interiors, increases your comfort around the office and home but also beneficial for your health. This is why it is necessary to choose the right way to do it. Either you can take the high road and do it yourself, or you can hire the professional to do the clea...

Read more

Creating research value needs more than just science – arts, humanities, social sciences can help

Rachel A. Ankeny, Professor of History and Associate Dean Research (Faculty of Arts), University of Adelaide

Actually yes, science and the arts do work together. from www.shutterstock.com This week we’re launching Making science for people, a series of articles that explores how humanities, arts and social sciences expertise is applied to problems typically corralled into the science and technology s...

Read more

Patriarchs on pedestals? How doctors are taught to improve their bedside manner

Mark Wilson, Associate professor, University of Wollongong

Student doctors need good role models to learn good patient communication. from www.shutterstock.comUp until around 30 years ago, in the days of paper patient files, doctors were on pedestals and patients generally did as they were told, in a more patriarchal model of patient care. Over 2,400 years ...

Read more

How the Anglican Church has hardened its stance against same-sex marriage

Muriel Porter, Honorary Research Fellow, Trinity College Theological School, University of Divinity

In the aftermath of the legalising of same-sex marriage in Australia, the Anglican Church has ramped up its discrimination against gay people to new heights.Not content simply with the discrimination built into the legislation – per ministers of religion to refuse to marry same-sex couples &nd...

Read more

rejecting neoliberalism shouldn't mean giving up on social liberalism

Richard Holden, Professor of Economics and PLuS Alliance Fellow, UNSW

shutterstockRichard Denniss’s Quarterly Essay, “Dead Right: How Neoliberalism Ate Itself and What Comes Next”, is a thought-provoking call to arms against an array of perceived ills – economic rationalism, market forces, small government, tax cuts, incentives, even corporate ...

Read more

Holidays & Travel

Dredging works underway Plantation Island

Tourists and workers travelling to popular tourist destination Plantation Island, Fiji, are set to benefit from safer access when marine channel dredging is completed at the end of June 2018...

Top 5 Tips for Traveling With Dogs

Travelling with your dog can be thrilling, but sometimes it can turn into a real nuisance. Unless you know how to properly restrain the pooch, whether it’ll be able to...

Top Island Destinations for 2018

When we picture island destinations in our minds, we often imagine a tropical beach of white sand, a sun lounger laid out in the shade of a line of palm...

Why Car Rental Excess Insurance is a Smart Choice

Some car rental agencies include basic damage cover in the standard rental fee, with the option to add on liability reduction, or excess insurance. The addition of excess insurance normally...

More Than a Third of Australians Feel 'Too Busy' With Work to Take a Holiday

New research from InterContinental Hotel & Resorts has unveiled a large number of Australians (32 percent) are simply too busy with work to take some much-needed rest and relaxation. Almost...

Matakauri Lodge and Mahu Whenua Lodge

TRIED, TRUE AND SOMETHING NEW  A luxurious accommodation package at Matakauri Lodge + Mahu Whenua Lodge South Island, New Zealand  Available 1 May, 2018 - 30 September, 2018   Central Otago, NEW ZEALAND –...

Heaven is the Adelaide Hills

Looking for a quick getaway? Enjoy food and wine? How about stunning countryside? Look no further! The Adelaide Hills has something for everyone. We flew to Adelaide for a weekend-getaway...

5 Amazing Australian Holiday Ideas

Australia is one of the most fantastic places in the world to travel, explore, and witness all of the beauty that Mother Nature has to offer. With so much rich...

Top Amenities You Enjoy by Renting Luxury Caravans for Road Trips

Do you love to undertake road trips? What the luxury cruises on the ocean are for ocean travelers, luxury caravanning is the same for land-lubbers. Traveling in a luxury caravan...

Fashion & Beauty

Simple Secrets To A More Confident Smile

We all know just how important first impressions are. After a handshake, what’s one of the first things people will notice about you? It’s your smile. A friendly smile is...

Improve Your Body Confidence and Feel Great

No matter how good you feel about yourself, sometimes you just can’t help but see a few little flaws that seem gigantic to you and make you feel self-conscious. Whether...

First-Timer Tips For Your First Lip Filler Appointment

Getting injectable lip fillers can be a quick and effective way to plump up your smile with minimal drama. They’re a cost-effective and safe way to boost the natural shape...

The Most Common Skin Conditions and How to Deal with Them

We often underestimate the importance of our skin, but as the largest organ in our body, and our primary layer of defense, it is constantly affected by many environmental factors...

Beach Babe Basics: Everything You Need to Look Stylish at the Beach

Summer is right around the corner, and this year, we all should make the best of it. Right now, it is not just about looking stylish on the streets, it...

Easy Dress-Up Tips for Lazy Girls

Look, getting all dolled up is fun, but you may not always be in the mood for it. Unfortunately, though, this is exactly when you are asked to go to...

HEALTH

My Health Yoga

Carrie-Anne Fields of My Health Yoga has taken her Gold Coast yoga teacher training worldwide. She started her health business 20 years ago aged 22 and has grown into a...

Fit Body 101 - Increase Your Fitness Effectiveness

You have to find some space for physical exercise in your weekly schedule in order to live a good life. Embracing this way of life is very beneficial because it...

The World of Dentistry: 5 Most Common Dental Procedures in Australia

Are you dissatisfied with the state of your pearly whites? Do you often experience discomfort and pain while eating and drinking? Well, be sure that you’re not the only one...

How You Can Conquer Your Dental Anxiety

Does the thought of going to the dentist fill you with dread? Well, you will be pleased to know that you are not the only one. A large number of...

Up and away: the impact of flying on your health

These school holidays, many people will take to the skies, unaware of the risks flying can pose to their health. Brisbane based house call doctor Ryan Harvey said it was important...

How to Lose Weight After 40

As you age, your metabolism slows down, which makes losing weight much harder. Additionally, your hormones start to fluctuate significantly, causing easier weight gain. Sticking to the same tricks you...

LIFE STYLE

Dry Carpet Cleaning Vs Steam Carpet Cleaning: Which one to Choose?

A clean carpet not only improve your interiors, increases your comfort around the office and home but also beneficial for your health. This is why it is necessary to choose...

Carpet cleaning: Things you need to know

Carpets are one of the most essential room interiors, and the kind of maintenance it requires is nothing worth comparison. We understand the importance of good health and hygiene at...

Get The Look: How to build a beautiful weatherboard home

Coastal, Queenslander and Contemporary Australia’s love affair with the weatherboard look can be seen in many of our historic and most popular styles – from the Queenslander to coastal and new...

The Fabrics That Make the Simple Indian Saree Sizzle

6 Yards of Sophistication and Sensuality Saree – an attire that can take you from boardroom to cruises; from kitchen to red-carpet; from lounging to marathon; from weddings to vacation –...

6 Tips for Mixing Design Styles Like a Pro

Each interior style is unique in its own way, creating a specific ambiance in our homes. While some accentuate simplicity and formality, others embrace playfulness and authenticity. Thus, you’re left...

Deborah Hutton: Designing My Dream Hamptons Inspired Home

Television presenter, magazine editor and media personality, Deborah Hutton is renovating her charming three bedroom house in Bronte, into her own Hamptons inspired forever home, with work due to be...

FOOD & DINING

Morning greens: the breakfast skincare regime

It’s safe to assume that most Aussies fail to eat enough greens. Although this was momentarily resolved with the rise and popularity of the green juice movement, the lack of...

Best Hidden Gem Hong Kong Restaurants

You finally find yourself enjoying the endless beauties of China and this fascinating city. In a place with so much variety, all your senses will be wide awake, and your...

JOHNNY DI FRANCESCO NAMED OFFICIAL AMBASSADOR OF EAT STREET MELBOURNE

Johnny Di Francesco, world champion pizzaiolo and owner of Melbourne’s Gradi Group of restaurants, is excited to announce he has been named official ambassador for Eat Street Melbourne 2018. As Ambassador...

The best Mother's Day gift EVER!

Whether it’s to celebrate a special occasion, or just wind down at the end of a long day, there’s nothing much better than pouring yourself a glass (or two…) of...

Sing for Your Supper at Chargrill Charlie’s

To celebrate the final curtain call of the Barden Bellas, Chargrill Charlie’s is giving you the chance to Sing for your Supper! Show off your best acapella vocals to win...

MAKE IT WINE TIME, ANY TIME

Whether it’s to celebrate a special occasion, or just wind down at the end of a long day, there’s nothing much better than pouring yourself a glass (or two…) of...