Western surge in obesity may have been caused by a virus

The obesity explosion that has swept the Western world over the past 30 years may have been caused by a virus, scientists have said.

Researchers have discovered new evidence for an illness they have called "infectobesity" – obesity that is transmitted from person to person, much like an infection. The agent thought to be responsible is a strain of adenovirus, versions of which cause the common cold. It has already been labelled the "fat bug".

There are more than 50 strains of adenovirus known to infect humans but only one, adenovirus 36, has been linked with human obesity.

Now scientists at the University of California, San Diego, have found that children who showed evidence of infection with adenovirus 36 were more likely to be fat. In tests on 124 children aged eight to 18, the virus was present in more than 20 per cent of those who were obese, compared with less than 6 per cent of the rest. Among those infected with adenovirus 36, four out of five were obese.

Children carrying the virus weighed on average almost 50lb more than those who were not. Among the obese children, who accounted for half the total, those with the virus weighed on average 35lb more than the rest.

Jeffrey Schwimmer, an associate professor of clinical paediatrics, who led the study published in the US journal Pediatrics, said: "This amount of extra weight is a major concern at any age, but is especially so for a child. Obesity can be a marker for future health problems like heart disease, liver disease and diabetes. An extra 35lb to 50lb is more than enough to greatly increase those risks.

"This work helps point out that body weight is more complicated than it's made out to be. And it is time that we move away from assigning blame in favour of developing a level of understanding that will better support efforts at both prevention and treatment.

"These data add credence to the concept that an infection can be a cause or contributor to obesity."

The idea of a viral cause for obesity was first raised a decade ago by Nikhil Dhurandhar, now a professor at the Pennington Biomedical Research Centre in Louisiana. He noticed that chickens which died during a flu epidemic in India in the 1980s – caused by an adenovirus – were plump, rather than thin and emaciated as expected.

Further studies revealed that one in five obese people showed signs of adenovirus infections and were on average more than 28lb heavier than people who had never been infected.

Sceptics pointed out that viruses had never been linked with a long-term disorder such as obesity. Dr Dhurandhar said the evidence was as clear as a map of the USA – where the obesity epidemic "has spread like a forest fire from the east coast to the west over the last 20 years".

Laboratory studies showed the virus infects immature fat cells, prompting them to proliferate and grow more quickly. Professor Schwimmer said: "This might be the mechanism for obesity but more work needs to be done."

Tam Fry, a spokesman for the UK National Obesity Forum said: "This is fascinating research which is starting to come out from the observations on chickens 10 years ago.

"Obesity is multifactorial – there is no single cause. Genes predispose to obesity, and family background. Then there is the onslaught by the food industry and the advertising industry. There is great value in as many researchers as possible looking in their own areas for the causes."

Life and Style
ebookNow available in paperback
ebooks
ebookPart of The Independent’s new eBook series The Great Composers
  • Get to the point
Latest stories from i100
Have you tried new the Independent Digital Edition apps?

ES Rentals

    Independent Dating
    and  

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

    iJobs Job Widget
    iJobs General

    Recruitment Genius: Senior IT Support / Projects Engineer

    £26000 - £29000 per annum: Recruitment Genius: This is an exciting opportunity...

    Recruitment Genius: Bench Joiner & Wood Machinist

    £20000 - £35000 per annum: Recruitment Genius: This busy local Joinery company...

    Recruitment Genius: Financial Adviser

    £20000 - £60000 per annum: Recruitment Genius: Are you recently QCA Level 4 qu...

    Recruitment Genius: Senior Director - Product Management

    £75000 - £85000 per annum: Recruitment Genius: They are the largest and fastes...

    Day In a Page

    Not even the 'putrid throat' could stop the Ross Poldark swoon-fest'

    Not even the 'putrid throat' could stop the Ross Poldark swoon-fest'

    How a costume drama became a Sunday night staple
    Miliband promises no stamp duty for first-time buyers as he pushes Tories on housing

    Miliband promises no stamp duty for first-time buyers

    Labour leader pushes Tories on housing
    Aviation history is littered with grand failures - from the the Bristol Brabazon to Concorde - but what went wrong with the SuperJumbo?

    Aviation history is littered with grand failures

    But what went wrong with the SuperJumbo?
    Fear of Putin, Islamists and immigration is giving rise to a new generation of Soviet-style 'iron curtains' right across Europe

    Fortress Europe?

    Fear of Putin, Islamists and immigration is giving rise to a new generation of 'iron curtains'
    Never mind what you're wearing, it's what you're reclining on

    Never mind what you're wearing

    It's what you're reclining on that matters
    General Election 2015: Chuka Umunna on the benefits of immigration, humility – and his leader Ed Miliband

    Chuka Umunna: A virus of racism runs through Ukip

    The shadow business secretary on the benefits of immigration, humility – and his leader Ed Miliband
    Yemen crisis: This exotic war will soon become Europe's problem

    Yemen's exotic war will soon affect Europe

    Terrorism and boatloads of desperate migrants will be the outcome of the Saudi air campaign, says Patrick Cockburn
    Marginal Streets project aims to document voters in the run-up to the General Election

    Marginal Streets project documents voters

    Independent photographers Joseph Fox and Orlando Gili are uploading two portraits of constituents to their website for each day of the campaign
    Game of Thrones: Visit the real-life kingdom of Westeros to see where violent history ends and telly tourism begins

    The real-life kingdom of Westeros

    Is there something a little uncomfortable about Game of Thrones shooting in Northern Ireland?
    How to survive a social-media mauling, by the tough women of Twitter

    How to survive a Twitter mauling

    Mary Beard, Caroline Criado-Perez, Louise Mensch, Bunny La Roche and Courtney Barrasford reveal how to trounce the trolls
    Gallipoli centenary: At dawn, the young remember the young who perished in one of the First World War's bloodiest battles

    At dawn, the young remember the young

    A century ago, soldiers of the Empire – many no more than boys – spilt on to Gallipoli’s beaches. On this 100th Anzac Day, there are personal, poetic tributes to their sacrifice
    Dissent is slowly building against the billions spent on presidential campaigns – even among politicians themselves

    Follow the money as never before

    Dissent is slowly building against the billions spent on presidential campaigns – even among politicians themselves, reports Rupert Cornwell
    Samuel West interview: The actor and director on austerity, unionisation, and not mentioning his famous parents

    Samuel West interview

    The actor and director on austerity, unionisation, and not mentioning his famous parents
    General Election 2015: Imagine if the leading political parties were fashion labels

    Imagine if the leading political parties were fashion labels

    Fashion editor, Alexander Fury, on what the leaders' appearances tell us about them
    Phumzile Mlambo-Ngcuka: Home can be the unsafest place for women

    Phumzile Mlambo-Ngcuka: Home can be the unsafest place for women

    The architect of the HeForShe movement and head of UN Women on the world's failure to combat domestic violence