• Sweden's news in English
 

'Vitamin supplements speed up cancer': study

Published: 30 Jan 2014 08:12 GMT+01:00

People who smoke or have lung cancer should think twice about taking vitamin supplements, according to a Swedish study Wednesday that showed certain antioxidants may make tumors grow faster.

Lab mice that already had cancer were given vitamin E and a drug called acetylcysteine, which sped the growth of their tumors and made them die faster than mice that did not ingest supplements.

"Antioxidants caused a three-fold increase in the number of tumors and also tumor aggressiveness, and the antioxidants caused the mice to die twice as fast," said study author Martin Bergo of the University of Gothenburg in Sweden.

"If we gave a low dose, tumors increased a little bit. And if we gave a high dose, tumors increased a lot."

Research on human lung cancer cells growing in a lab dish also showed that the antioxidants caused the cells to multiply faster than they would have alone, suggesting the same might happen in human patients. While more work needs to be done to confirm the effect in people, Bergo urged those with lung cancer, chronic obstructive pulmonary disease and smokers to take caution.

"You can walk around with an undiagnosed lung tumor for a long time," he said. "If you are in this patient group, then taking extra antioxidants might be harmful and it could speed up the growth of that tumor."

The body produces its own antioxidants to prevent DNA damage from chemicals known as free radicals, but needs more from healthy foods like leafy greens, vegetables and fruits to stay healthy. However, a large body of research on antioxidant supplements in humans has returned mixed results.

Some studies have suggested that people who take antioxidant supplements actually face a higher risk of cancer than those who do not.

One such study of nearly 30,000 men in Finland, which concluded in 1993, found that smokers who took the antioxidant beta carotene had a higher rate of cancer and greater risk of dying. Other studies, such as the SELECT trial which enrolled 35,000 US and Canadian men beginning in 2001, found that men who took vitamin E were more likely to get prostate cancer.

"We haven't completely ironed out which vitamins, if any, may prevent cancer and which may cause cancer development or growth," said Benjamin Levy, director of thoracic medical oncology at Mount Sinai Beth Israel Hospital in New York.

"This study may help explain the negative findings from prior clinical lung cancer studies, including the ATBC and SELECT studies," said Levy, who was not involved in the research.

Researchers said their findings suggest antioxidants help tumors cut down on harmful free radicals, just as they do in normal cells, allowing the tumors to grow faster. Free radicals can damage cells and possibly lead to cancer. But free radicals exist in cancer cells, too, explained Bergo.

"So it is also in the tumor's interest to suppress free radicals, and that is what we are doing when we take extra antioxidants, or give it to the mice in this case," he told reporters.

A protein called p53 can sense when DNA has been damaged by the buildup of molecules called reactive oxygen species (ROS). P53 can stop the growth of the cell and thereby stop the cancer. When extra antioxidants reduce the level of ROS, this "allows the cancer cells to escape their own defense system," said co-author Per Lindahl from the University of Gothenburg.

Of particular concern is the finding that acetylcysteine increased tumor growth, since the drug is often given to patients with chronic obstructive pulmonary disease (COPD) as a way to help them breathe better and clear mucus from their lungs.

"We think that the use of acetylcysteine in this patient group should probably be carefully evaluated," said Bergo.

He added that researchers are now combing through data registries to find out if COPD patients -- including people with chronic bronchitis and emphysema -- have higher cancer rates after taking the drug. The research appears in the journal Science Translational Medicine.

Your comments about this article

Today's headlines
Swede wins world boxing title
Badou, left, connects with Anthony Dirrell during the fight in Chicago. Photo: AFP

Swede wins world boxing title

Sweden's Badou Jack claimed the World Boxing Council's super middleweight title as he outpointed previously unbeaten Anthony Dirrell in Chicago on Friday night. READ  

Swedish police officers praised by New Yorkers
The Swedish police heroes meet with NYPD heads. Photo: New York Police Department/TT

Swedish police officers praised by New Yorkers

A video has emerged of Swedish off-duty police officers breaking up a violent fight on the New York subway. READ  

Eighth happiest: why are the Swedes not pleased?
Swedes are the eighth happiest people in the world. Photo: Susanne Walström/imagebank.sweden.se

Eighth happiest: why are the Swedes not pleased?

Sweden is the eighth happiest country in the world, according to the UN. But the result has not gone down well in the Nordic country. The Local caught up with an expert to find out why. READ  

Löfven: Palestine move was done by the book
Stefan Löfven gets a grilling from the powerful Constitutional Affairs Committee of the Swedish parliament. Photo. Henrik Montgomery/Scanpix

Löfven: Palestine move was done by the book

Sweden’s Prime Minister Stefan Löfven has denied that he bypassed parliament when the country recognized Palestine last year. READ  

Early summer sweeps in across much of Sweden
Swedes enjoying the sunshine in Stockholm. Photo: The Local

Early summer sweeps in across much of Sweden

Get the barbeque out and your swim suit ready – summer is here. In fact, western and parts of central Sweden have been able to enjoy the year's warmest season for the past seven days. READ  

Defence giant Saab sees surprise fall in profits
Saab chief executive Håkan Buskhe at a press conference on Friday. Photo: Sören Andersson/TT

Defence giant Saab sees surprise fall in profits

Swedish defence giant Saab announced a surprise drop in first-quarter operating profits on Friday, while the company took a 3.8 percent tumble on the Stockholm stock market. READ  

Need more space? Check out Sweden's priciest flat
An artist's impression of the sitting room of Sweden's most expensive apartment. Image: Sivkraft

Need more space? Check out Sweden's priciest flat

Is money burning a hole in your pocket? Sweden's most expensive apartment in history could help you offload some cash. READ  

Thieves crash loader into store in Stockholm raid
Thieves crashed a loader through the walls of a Swedish electronics store. Photo: Maja Suslin/TT

Thieves crash loader into store in Stockholm raid

Swedish police are investigating after thieves carried out an advanced smash and grab heist on an electronics store in Stockholm on Friday morning. READ  

The Local Recipes
How to make Swedish strawberry cream cake
Strawberry cream cake is a Swedish favourite. Photo: John Duxbury

How to make Swedish strawberry cream cake

As the first strawberries of the season went on sale in southern Sweden this week for a whopping 894 kronor ($103) a box, we bring you this timely recipe for traditional Swedish strawberry cream cake by food writer John Duxbury. READ  

Sweden telecom network 'vulnerable to attack'
Swedish landlines could be vulnerable to hacking, according to newspaper Dagens Nyheter. Photo: Lars Pehrson/SvD/SCANPIX

Sweden telecom network 'vulnerable to attack'

Outsourcing and serious security flaws by external suppliers could leave Sweden's telecommunications network open to attack – and make it easier for foreign powers to tap into them unnoticed, an IT security expert has said. READ  

RECEIVE OUR NEWSLETTER AND ALERTS
National
What's on in Sweden: April 23rd - 30th
Features
My bizarre Swedish habits that foreigners just don't understand
Stockholm School of Economics
Sponsored Article
How the Stockholm School of Economics changes expat lives
National
Brits in Sweden face NHS black hole
Swedish Hasbeens
Sponsored Article
Is the world wrong to connect Sweden with sex?
Blog updates

24 April

Editor’s blog, April 24th (The Local Sweden) »

"Hi readers, Spring has well and truly arrived, as evidenced by the start of strawberry season. The..." READ »

 

15 April

Gång, timme, tid & dags (The Swedish Teacher) »

"Hej! In this article I will talk about “gång”, “timmar”, “dags” and “tid”, because they all translate..." READ »

 
 
 
Business & Money
The Swedish regions where you're least likely to stay jobless
Gallery
People-watching: April 22nd
Sport
Sweden's Eriksson joins row over foreign England player quotas
National
MEP says ignoring migrant crisis like 'Sweden's Holocaust appeasement'
Gallery
IN PICTURES: The Swedish mining town that's being moved
National
How much would you pay for first Swedish strawberries of 2015?
Gallery
Property of the week: Kungsholmen, Stockholm
Sponsored Article
Want to study in Sweden? Read why Stockholm is the best choice
Photo: TT
National
Get set for a sunny week in Sweden
Sponsored Article
Does far-north Sweden have to punch above its weight?
National
Refugees in Sweden fear for families lost at sea
National
Syria claims ‘most dangerous’ Isis leaders are Scandinavian
Gallery
People-watching: April 18th
National
Swedish researchers pore over link between coffee and cancer
Features
What you can buy in Sweden for the price of a London shed
National
What's on in Sweden this week
National
Swedes launch first donut into space
Politics
Is Sweden returning to 1990s social democratic welfare politics?
National
Mamma Mia! Abba entertainment venue set to open in Stockholm
Gallery
People-watching: April 15th
National
Why Sweden is top place in the world for expats to raise children
National
Swedish 'submarine' was civilian boat
National
Why has a US town got pulled into a Swedish spelling row?
Gallery
Property of the week: Hovås, Gothenburg
National
What does Zlatan think of his ban?
National
Swedish teenagers help rebuild Breivik massacre island
National
Would you live in a steel box?
National
How an act of kindness by one Syrian immigrant went viral
Gallery
People-watching: April 8th
National
Swedish bids for Billboard fame
National
Swedish monkeys denied Saudi visas
National
Sunny spring weather predicted
Sponsored Article
'Impossible' to run Skanska without Bromma Airport
National
Half of Swedes want begging ban
Gallery
Property of the week: Gotland
National
Why are expats less likely to settle down with Swedes?
Sport
What does Sweden think of Zlatan's recent outburst?
Society
Get to grips with Sweden's most bizarre Easter traditions
Gallery
People-watching: April 1st
National
The Local's best April Fools' gags
National
US spy agency to feature in new 'Stieg Larsson' book sequel
National
Beaver bite at Swedish bus stop
Gallery
Property of the week: Åreda
Sponsored Article
'Sweden must embrace openness and diversity'
Latest news from The Local in Austria

More news from Austria at thelocal.at

Latest news from The Local in Switzerland

More news from Switzerland at thelocal.ch

Latest news from The Local in Germany

More news from Germany at thelocal.de

Latest news from The Local in Denmark

More news from Denmark at thelocal.dk

Latest news from The Local in Spain

More news from Spain at thelocal.es

Latest news from The Local in France

More news from France at thelocal.fr

Latest news from The Local in Italy

More news from Italy at thelocal.it

Latest news from The Local in Norway

More news from Norway at thelocal.no

3,338
jobs available
PSD Media
PSD Media is marketing company that offers innovative solutions for online retailers. We provide modern solutions that help increase traffic and raise conversion. Visit our site at:
psdmedia.se