• Switzerland's news in English

Swiss uncover why ex-smokers gain weight

AFP · 29 Aug 2013, 18:19

Published: 29 Aug 2013 18:19 GMT+02:00

Facebook Twitter Google+ reddit

Studies have shown that quitting smoking leads to an average weight gain of four to five kilogrammes (nine to 11 pounds) in the first year.
But according to researchers at Zurich University Hospital, former smokers who bulk up may not be eating more than before they kissed their cigarettes goodbye.
Noting that even people who cut back on calorie intake after quitting smoking tend to gain weight, Professor Gerhard Rogler said he and his colleagues had discovered another potential explanation: a change in the composition of the intestinal flora among smokers who kick the habit.
Their study, supported by the Swiss National Science Foundation and published in peer-reviewed scientific journal PLoS One, found that when a person stops smoking, the diversity of bacterial strains in their intestines shifts.

It more resembles the gut flora found in people with obesity.
Both recent non-smokers and obese people tend to have more of two bacteria types, Proteobacteria and Bacteroidetes, Rogler told AFP.
These germs are believed to use energy more efficiently and break down otherwise indigestible fibres — and as a result, more of what the person eats is transformed into fat rather than excreted as waste.
The researchers studied the genetic profile of intestinal bacteria found in faecal samples provided by 20 volunteers over nine weeks.
The participants comprised five non-smokers, five smokers and 10 people who had quit smoking one week after the study began.
Little difference was seen in the bacterial biodiversity among the persistent smokers and non-smokers.
But among those who had just given up smoking, there was a clear shift towards more Proteobacteria and Bacteroidetes, the study showed.
Over the study period, the people who had quit smoking also gained an average of 2.2 kilos (4.8 pounds), even though they insisted that their eating and drinking habits were unchanged.
"Under the same living conditions, they gained weight after the cessation of smoking, and they showed a change in the microbiota," Rogler said.
While researchers have yet to prove a clear connection between the two developments, he pointed out that a number of other studies have also showed a link between intestinal bacteria and weight gain.
On Wednesday, a study published in the journal Nature found that individuals with low bacterial "richness" in their intestines were more prone to obesity and associated diseases such as diabetes, heart and cholesterol problems.

Six bacterial species appear to play a key role in promoting this diversity.
Rogler said that more research was needed to answer the many questions that arise from such discoveries.
But he said it was clear we should pay more attention to how the environment influences gut functions.
"Nobody believed the people who stopped smoking and said they weren't eating more but still gained weight. Perhaps we simply should be more willing to believe what people tell us," he said.

Facebook Twitter Google+ reddit

Your comments about this article

Today's headlines
Montreux throws hat in Olympic rings
Could Montreux host the 2026 Games? Photo: Ivo Scholz/Swiss Tourism

Montreux is to put itself forward as the host city for the 2026 winter Olympics as part of a potential bid by the cantons of Valais and Vaud.

Geneva car share scheme could help reduce city traffic
Catch a Car is aimed at short hops within a city. Photo: Catch a Car

Catch a Car, already in Basel, launches in Geneva next month.

Swiss women will ‘work for free’ for the rest of year
Female employees in Switzerland earn 19.3 percent less than their male colleagues. File photo: Randy Kashka

Switzerland's gender pay gap means from today, Friday October 21st, women in the country will effectively be working for free for the rest of 2016.

Swiss luxury watches stolen in Paris raid
Police outside the Girard-Perregaux watch store on Thursday. Photo: Bertrand Guay/AFP

The 10 Girard-Perregaux watches are worth half a million euros in total.

Brother-in-law arrested over murder of Swiss teacher
The victim worked in a school in Stabio, near the town of Mendrisio. Photo: Oliver Graf

The primary school teacher was found dead in Ticino earlier this week.

Inside Switzerland’s largest nuclear bunker – 40 years on
Designed to house 20,000 people, the bunker was built in and over two motorway tunnels. Photo: Unterirdisch Ueberleben

The Local takes a tour of the Sonnenberg bunker in Lucerne, opened 40 years ago at the height of the Cold War.

Ten Swiss ski resorts named most expensive in Europe
File photo: Renato Bagattini/Swiss Tourism

Skiers in Switzerland pay the highest prices for their ski passes of anywhere in Europe, according to research.

Eco group fights Bern over wind farm plans
There are currently more than 30 wind farms in Switzerland. Photo: Alpiq

Wind turbines are “gigantic and destructive” machines, says Paysage Libre Suisse.

Vegan wins battle to be accepted by Swiss army
Antoni Da Campo will now carry out his military service. Photo: Antoni Da Campo

A Swiss man who was told he would not be accepted for military service because of his strict veganism has finally succeeded in making the army change its mind.

Geneva terror suspects to receive compensation
File photo: Emran Kassim

The Swiss public prosecutor has dropped the case against them.

Sponsored Article
How to vote absentee from abroad in the US elections
Photo: Richard Juilliard/AFP
Man makes Geneva airport bomb threat ‘for a joke’
Sponsored Article
Last chance to vote absentee in the US elections
Photo: AFP
Solar Impulse team reveals plans for unmanned plane
File photo: Martin Abegglen
Swiss to vote on passport rules for 3rd gen foreigners
Sponsored Article
How to vote absentee from abroad in the US elections
Photo: AFP
Swiss wingsuit hotspot Lauterbrunnen won’t impose ban
Photo: Swiss Tourism
Six reasons Switzerland isn’t as boring as you might think
Photo: Swiss Tourism
Report: Switzerland one of world’s best places for girls
Photo: The Local
Thief returns Swiss cow bells worth thousands
File photo: Wikimedia Commons
One in three rapists isn’t locked up: statistics
Photo: activistin.ch
Tampon-tax protest turns Zurich fountains red
Photo: AFP
Geneva police to lift ban on bearded officers
Photo: Marcel Gillieron/AFP
Suicide chef’s restaurant keeps Michelin stars
Photo: Lara de Salis
11 things the Swiss get tired of hearing abroad
Photo:  Ivo Scholz/Swiss-image.ch
Survey: expats in Switzerland have money but few friends
Photo: AFP
Swiss press criticize Bern’s 'capitulation' on immigration
Photo: Jura Trois Lacs tourism
German ex-policeman is Swiss city’s new hermit
Photo: Dmitry A. Mottl
Ticino votes to favour local workers over foreigners
Photo: file
Some deodorants could cause breast cancer: Swiss study
Photo: Royal Savoy
In pictures: Inside the latest Swiss luxury hotel
Photo: AFP
Geneva airport bomb hoaxer faces 90,000-franc bill
Photo: Schaffhausen police
Mother leaves toddler son alone in car to go clubbing
Photo: Fabrice Coffrini/AFP
Swiss populist attacked by knife-wielding pensioner
Photo: File
Bern argues over passports for 3rd generation foreigners
Photo: Broad Bean Media
Muslim pupils must shake hands – ‘no ifs and buts’
jobs available