Featured Research

from universities, journals, and other organizations

Fat Transforms Vitamin C From 'Good Cop' Into 'Bad Cop'

Date:
September 4, 2007
Source:
BMJ Specialty Journals
Summary:
Fat in the stomach may cause vitamin C to promote, rather than prevent, the formation of certain cancer causing chemicals, reveals new research. Fat remains in the proximal stomach for some time after a meal and also makes up a substantial amount of the cells lining the stomach, say the authors.

Fat in the stomach may cause vitamin C to promote, rather than prevent, the formation of certain cancer causing chemicals, reveals research published ahead of print in the journal Gut.

Related Articles


The researchers analysed the impact of both fat (lipid) and vitamin C (ascorbic acid) on nitrite chemistry in the upper (proximal) stomach, which is especially vulnerable to pre-cancerous changes and tumour growth.

Nitrites, which are present in human saliva, and in certain preserved foodstuffs, may be converted to cancer causing compounds called nitrosamines. Nitrosamines are formed in acidic conditions, such as those afforded by stomach acid, but vitamin C inhibits their formation, by converting nitrite to nitric oxide.

The researchers replicated the chemical conditions of the proximal stomach and measured the formation of nitrosamines, oxygen, and nitric oxide.

Without fat, vitamin C curbed the levels of two nitrosamines by a factor of between five and 1000. And it completely eliminated the production of the other two.

But when 10% fat was added, vitamin C actually boosted the production of nitrosamines between 8 and 140-fold. Fat remains in the proximal stomach for some time after a meal and also makes up a substantial amount of the cells lining the stomach, say the authors.

Nitric oxide is formed when vitamin C reacts with nitrite in acid. However, the nitric oxide can diffuse into fat and then react with oxygen to form nitrosoamine generating chemicals.

The findings may be relevant to the recent observations that vitamin C supplements fail to reduce cancer risk, say the authors.

Reference: Fat transforms ascorbic acid from inhibiting to promoting acid-catlysed N-nitrosation Online First Gut 2007; doi: 10.1136/gut.2007.12857


Story Source:

The above story is based on materials provided by BMJ Specialty Journals. Note: Materials may be edited for content and length.


Cite This Page:

BMJ Specialty Journals. "Fat Transforms Vitamin C From 'Good Cop' Into 'Bad Cop'." ScienceDaily. ScienceDaily, 4 September 2007. <www.sciencedaily.com/releases/2007/09/070903204800.htm>.
BMJ Specialty Journals. (2007, September 4). Fat Transforms Vitamin C From 'Good Cop' Into 'Bad Cop'. ScienceDaily. Retrieved January 29, 2015 from www.sciencedaily.com/releases/2007/09/070903204800.htm
BMJ Specialty Journals. "Fat Transforms Vitamin C From 'Good Cop' Into 'Bad Cop'." ScienceDaily. www.sciencedaily.com/releases/2007/09/070903204800.htm (accessed January 29, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Thursday, January 29, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Malnutrition on the Rise as Violence Flares in C. Africa

Malnutrition on the Rise as Violence Flares in C. Africa

AFP (Jan. 28, 2015) Violence can flare up at any moment in Bambari with only a bridge separating Muslims and Christians. Malnutrition is on the rise and lack of water means simple cooking fires threaten to destroy makeshift camps where people are living. Duration: 00:40 Video provided by AFP
Powered by NewsLook.com
Poultry Culled in Taiwan to Thwart Bird Flu

Poultry Culled in Taiwan to Thwart Bird Flu

Reuters - News Video Online (Jan. 28, 2015) Taiwan culls over a million poultry in efforts to halt various strains of avian flu. Julie Noce reports. Video provided by Reuters
Powered by NewsLook.com
Media Criticizing Parents For Not Vaccinating Children

Media Criticizing Parents For Not Vaccinating Children

Newsy (Jan. 28, 2015) As the Disneyland measles outbreak continues to spread, the media says parents who choose not to vaccinate their children are part of the cause. Video provided by Newsy
Powered by NewsLook.com
Shark Bite Victim Making Amazing Recovery

Shark Bite Victim Making Amazing Recovery

AP (Jan. 27, 2015) A Texas woman who lost more than five pounds of flesh to a shark in the Bahamas earlier this month could be released from a Florida hospital soon. Experts believe she was bitten by a bull shark while snorkeling. (Jan. 27) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins