Episode available within Canada only.
Listen to an interview with director Leora Eisen and author Tim Spector on The Current

Eat less, move more. That’s been the mantra of the weight loss movement for decades.  But as those who have fought the battle of the bulge will tell you, there’s a lot more to obesity than just too much junk food or too little willpower. Even when genes are taken into account, scientists have struggled to explain why one person can eat cake and stay skinny, while another munches on carrots and can’t shed a pound.

Now, exciting new research reveals there is a missing piece to the obesity puzzle, one that is highly complex and intensely personal: gut microbes.

Inside our intestines, there’s an entire ecosystem – our own “inner rainforest” -  made up of microorganisms so small that millions could fit into the eye of a needle. But these tiny bugs that live in our gut are proving key to human health and the obesity epidemic.

microbesCould microbes be the missing key to weight loss?

Some of these bacteria are nasty pathogens that lead to diseases. As a result, conventional wisdom has given all bacteria a bad rap – until recently, when researchers began proving what one science writer calls a  “subversive” idea: bacteria are actually our biggest allies. By targeting them as the enemy, we’ve damaged our bodies’ own biological systems, including weight control. 

Microbes help us digest food, harvest calories, provide us with energy, produce crucial vitamins, regulate appetite, protect our immune system and fend off the bad guys. But because of our modern lifestyle, including a highly processed Western diet and overuse of antibiotics, some of the species of bacteria that once lived in our gut are on the verge of extinction.

Our microbes need to eat, but we’re starving them by failing to nourish them with the proper foods. The result? Unhealthy guts, and an obesity rate that has skyrocketed.

Time  SpectorTim Spector cooking for his family

According to geneticist Tim Spector, author of the new book “The Diet Myth: The Real Science Behind What We Eat”, the most important diet myth is that, “like identical lab rats”, we all respond to food and consume calories the same way. 

But just like a fingerprint, each person’s microbiome is unique, and so is the way diet impacts our weight and our health. So the diet that works for a British scientist may be radically different from a hunter-gatherer in Tanzania, or even the person living next door.

In It Takes Guts we’ll explore the links between microbes, diet and weight. We’ll discover surprising new information about the food we eat, and the food our microbes love to munch on. And we’ll meet the researchers who are applying what they’ve learned in the lab to their everyday lives, and experimenting on themselves, including:

With the help of colourful graphic animations, we’ll learn how we’ve damaged our microbiomes, and discover ways to restore our “inner rainforest”. As one researcher notes, “You never eat alone. Because whatever food you put in you're feeding trillions of your microbes.”

In the battle of the bulge, should we learn to trust our gut?

Directed by Leora Eisen and executive produced by Gordon Henderson at 90th Parallel Productions in association with CBC.

Credits (Click to expand)

produced, directed and written by
Leora Eisen

executive producer
Gordon Henderson

Michael Hannan

Michael Grippo Csc
Nigel Kinnings

production manager
Susanne Cuffe

sound recordist
Mike Josselyn
Dustin Eddo
John Grove
Larry Macdonald
Dave Scaringe
Bill Williams

original music
Bruce Fowler

associate producer
Rita Kotzia

Leora Eisen
Rita Kotzia

visual researcher
Gina Cali

assistant editor
James Yates

audio mix
Mike Duncan

additional audio mix
Shane Duncan

Mark Alberts

online editor/colourist
Dan Johnston

visual archives
Archives Film/Getty Images
Jeff Leach
The Human Food Project
The Touch of Life Films
Warrior Poets
WPA Film Library

special thanks
British Science Museum
Guy Holbrow
Twins UK

produced by

© 2015 90th Parallel Productions Ltd.

for the CBC

director of production
Alexandra Lane

director of finance
Julie Lawlor

executive in charge of production
Sue Dando

executive director
Documentary Programming
Mark Starowicz

executive director
Unscripted Content
Jennifer Dettman

The Nature of Things
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produced by
Canadian Broadcasting Corporation


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