Gut bacteria could be behind why some 'identical' people are fatter than others

Findings of research on mice could mean re-colonising obese people's guts with healthy, lean-triggering bacteria could help them lose weight

Science Editor

Bacteria growing naturally in the human gut could be playing a decisive role in determining whether someone becomes overweight or obese according to a remarkable study involving laboratory mice fed with bacterial gut “fauna” from fat and thin people.

The results lend further weight to earlier studies showing that gut bacteria, which are more numerous than the cells of the human body, probably play a significant role in raising or lowering the risk of someone putting on weight.

In the latest study scientists isolated gut bacteria from identical and non-identical twins, where one sibling was obese and the other was lean, and found that the bacteria caused mice to become lean or overweight depending on whether they received the bacteria from the lean or obese twin respectively.

The scientists also found which bacterial species are involved. The microbial group known as the Bacteroides, for example, was more prevalent in lean individuals and was also found to play a protective role against fat accumulation in mice fed on certain diets.

The mice in the study were specially bred “germ-free” animals lacking their own microbial gut fauna. When fed a standard diet with the added microbes from the human gut, those receiving bacteria from obese individuals gained more fat than mice fed on bacteria from lean individuals, said Jeffrey Gordon of Washington University School of Medicine.

“This wasn't attributable to differences in the amount of food they consumed, so there was something in the microbiota that was able to transmit this trait. Our question became: What were the components responsible?” Dr Gordon said.

The transplanted gut microbes from humans led to metabolic changes in the mice that caused them to build up fat tissue in their bodies, which is also the key feature seen in people who are overweight or obese.

When the two sets of mice were put together in the same cage, the obese mice became lean. This indicated that they had shared their microbial fauna – mice eat each other’s droppings – and that the “lean” bacteria were winning out in the battle to colonise the guts of the “obese” mice, Dr Gordon said.

This suggests that re-colonising the gut of obese people with healthy, lean-triggering bacteria may help them to lose weight, provided they also follow other advice on diet and exercise, he said.

“In the future, the nutritional value and the effects of food will involve significant consideration of our microbiota – and developing healthy, nutritious foods will be done from the inside-out, not just the outside-in,” he added.

Start your day with The Independent, sign up for daily news emails
PROMOTED VIDEO
ebooks
ebooksA special investigation by Andy McSmith
Arts and Entertainment
This weekend's 'Big Hero 6' by Disney Animation Studios
arts + ents
News
i100
News
Budapest, 1989. Sleepware and panties.
newsDavid Hlynsky's images of Soviet Union shop windows shine a light on our consumerist culture
Arts and Entertainment
Eleanor Catton has hit back after being accused of 'treachery' for criticising the government.
books
News
In humans, the ability to regulate the expression of genes through thoughts alone could open up an entirely new avenue for medicine.
science
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Transport Administrator / Planner

£20000 - £35000 per annum: Recruitment Genius: This fast growing reinforcing s...

Austen Lloyd: Corporate Tax Associate - London

Excellent Package: Austen Lloyd: CITY - HIGHEST QUALITY INTERNATIONAL FIRM - A...

Austen Lloyd: Senior Law Costs - London City

Excellent Package: Austen Lloyd: CITY - EXCELLENT FIRM - We have an outstandin...

Austen Lloyd: In-House Solicitor / Company Secretary - London

Excellent Package: Austen Lloyd: IN-HOUSE - NATIONAL CHARITY - An exciting and...

Day In a Page

Isis hostage crisis: The prisoner swap has only one purpose for the militants - recognition its Islamic State exists and that foreign nations acknowledge its power

Isis hostage crisis

The prisoner swap has only one purpose for the militants - recognition its Islamic State exists and that foreign nations acknowledge its power, says Robert Fisk
Missing salvage expert who found $50m of sunken treasure before disappearing, tracked down at last

The runaway buccaneers and the ship full of gold

Salvage expert Tommy Thompson found sunken treasure worth millions. Then he vanished... until now
Homeless Veterans appeal: ‘If you’re hard on the world you are hard on yourself’

Homeless Veterans appeal: ‘If you’re hard on the world you are hard on yourself’

Maverick artist Grayson Perry backs our campaign
Assisted Dying Bill: I want to be able to decide about my own death - I want to have control of my life

Assisted Dying Bill: 'I want control of my life'

This week the Assisted Dying Bill is debated in the Lords. Virginia Ironside, who has already made plans for her own self-deliverance, argues that it's time we allowed people a humane, compassionate death
Move over, kale - cabbage is the new rising star

Cabbage is king again

Sophie Morris banishes thoughts of soggy school dinners and turns over a new leaf
11 best winter skin treats

Give your moisturiser a helping hand: 11 best winter skin treats

Get an extra boost of nourishment from one of these hard-working products
Paul Scholes column: The more Jose Mourinho attempts to influence match officials, the more they are likely to ignore him

Paul Scholes column

The more Jose Mourinho attempts to influence match officials, the more they are likely to ignore him
Frank Warren column: No cigar, but pots of money: here come the Cubans

Frank Warren's Ringside

No cigar, but pots of money: here come the Cubans
Isis hostage crisis: Militant group stands strong as its numerous enemies fail to find a common plan to defeat it

Isis stands strong as its numerous enemies fail to find a common plan to defeat it

The jihadis are being squeezed militarily and economically, but there is no sign of an implosion, says Patrick Cockburn
Virtual reality thrusts viewers into the frontline of global events - and puts film-goers at the heart of the action

Virtual reality: Seeing is believing

Virtual reality thrusts viewers into the frontline of global events - and puts film-goers at the heart of the action
Homeless Veterans appeal: MP says Coalition ‘not doing enough’

Homeless Veterans appeal

MP says Coalition ‘not doing enough’ to help
Larry David, Steve Coogan and other comedians share stories of depression in new documentary

Comedians share stories of depression

The director of the new documentary, Kevin Pollak, tells Jessica Barrett how he got them to talk
Has The Archers lost the plot with it's spicy storylines?

Has The Archers lost the plot?

A growing number of listeners are voicing their discontent over the rural soap's spicy storylines; so loudly that even the BBC's director-general seems worried, says Simon Kelner
English Heritage adds 14 post-war office buildings to its protected lists

14 office buildings added to protected lists

Christopher Beanland explores the underrated appeal of these palaces of pen-pushing
Human skull discovery in Israel proves humans lived side-by-side with Neanderthals

Human skull discovery in Israel proves humans lived side-by-side with Neanderthals

Scientists unearthed the cranial fragments from Manot Cave in West Galilee