Featured Research

from universities, journals, and other organizations

Couple of weekly portions of oily fish can help ward off stroke; But fish oil supplements don't have the same effect, study finds

Date:
October 30, 2012
Source:
BMJ-British Medical Journal
Summary:
Eating at least two servings of oily fish a week is moderately but significantly associated with a reduced risk of stroke, finds a new study.

Mackerel fish on ice.
Credit: Alexander Raths / Fotolia

Eating at least two servings of oily fish a week is moderately but significantly associated with a reduced risk of stroke, finds a study published on the British Medical Journal website.

Related Articles


But taking fish oil supplements doesn't seem to have the same effect, say the researchers.

Regular consumption of fish and long chain omega 3 fatty acids has been linked with a reduced risk of coronary heart disease and current guidelines recommend eating at least two portions of fish a week, preferably oily fish like mackerel and sardines. But evidence supporting a similar benefit for stroke remains unclear.

So an international team of researchers, led by Dr. Rajiv Chowdhury at Cambridge University and Professor Oscar H. Franco at Erasmus MC Rotterdam, analysed the results of 38 studies to help clarify the association between fish consumption and risk of stroke or mini-stroke (transient ischaemic attack or TIA). Collectively, these conditions are known as cerebrovascular disease.

The 38 studies involved nearly 800,000 individuals in 15 countries and included patients with established cardiovascular disease (secondary prevention studies) as well as lower risk people without the disease (primary prevention studies). Differences in study quality were taken into account to identify and minimise bias.

Fish and long chain omega 3 fatty acid consumption was assessed using dietary questionnaires, identifying markers of omega 3 fats in the blood, and recording use of fish oil supplements. A total of 34,817 cerebrovascular events were recorded during the studies.

After adjusting for several risk factors, participants eating two to four servings a week had a moderate but significant 6% lower risk of cerebrovascular disease compared with those eating one or fewer servings of fish a week, while participants eating five or more servings a week had a 12% lower risk.

An increment of two servings per week of any fish was associated with a 4% reduced risk of cerebrovascular disease. In contrast, levels of omega 3 fats in the blood and fish oil supplements were not significantly associated with a reduced risk.

Several reasons could explain the beneficial impact of eating fish on vascular health, say the authors. For example, it may be due to interactions between a wide range of nutrients, like vitamins and essential amino acids, commonly found in fish. Alternatively, eating more fish may lead to a reduction in other foods, like red meat, that are detrimental to vascular health. Or higher fish intake may simply be an indicator of a generally healthier diet or higher socioeconomic status, both associated with better vascular health.

The differences seen between white and oily fish may be explained by the way they are typically cooked (white fish is generally battered and deep fried, adding potentially damaging fats).

Although there's a possibility that some other unmeasured (confounding) factor may explain their results, the authors conclude that "they reinforce a potentially modest beneficial role of fish intake in the cause of cerebrovascular disease."

In addition, they say their findings are in line with current dietary guidelines that encourage fish consumption for all; and intake of fish oils to people with pre-existing or at high risk of heart disease. They also support the view that future nutritional guidelines should be principally "food based."

In an accompanying editorial, authors from the Division of Human Nutrition at Wageningen University suggest that although it is "reasonable" to advise patients that eating one or two portions of fish per week could reduce the risk of coronary heart disease and stroke, any benefit of long chain omega 3 fatty acid supplementation is likely to be small. They say it is possible, however, that patients with additional risk factors such as diabetes may benefit.


Story Source:

The above story is based on materials provided by BMJ-British Medical Journal. Note: Materials may be edited for content and length.


Cite This Page:

BMJ-British Medical Journal. "Couple of weekly portions of oily fish can help ward off stroke; But fish oil supplements don't have the same effect, study finds." ScienceDaily. ScienceDaily, 30 October 2012. <www.sciencedaily.com/releases/2012/10/121030210349.htm>.
BMJ-British Medical Journal. (2012, October 30). Couple of weekly portions of oily fish can help ward off stroke; But fish oil supplements don't have the same effect, study finds. ScienceDaily. Retrieved November 28, 2014 from www.sciencedaily.com/releases/2012/10/121030210349.htm
BMJ-British Medical Journal. "Couple of weekly portions of oily fish can help ward off stroke; But fish oil supplements don't have the same effect, study finds." ScienceDaily. www.sciencedaily.com/releases/2012/10/121030210349.htm (accessed November 28, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Friday, November 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Research on Bats Could Help Develop Drugs Against Ebola

Research on Bats Could Help Develop Drugs Against Ebola

AFP (Nov. 28, 2014) In Africa's only biosafety level 4 laboratory, scientists have been carrying out experiments on bats to understand how virus like Ebola are being transmitted, and how some of them resist to it. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
New Dinosaur Species Found in Museum Collection

New Dinosaur Species Found in Museum Collection

Reuters - Innovations Video Online (Nov. 27, 2014) A British palaeontologist has discovered a new species of dinosaur while studying fossils in a Canadian museum. Pentaceratops aquilonius was related to Triceratops and lived at the end of the Cretaceous Period, around 75 million years ago. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Tryptophan Isn't Making You Sleepy On Thanksgiving

Tryptophan Isn't Making You Sleepy On Thanksgiving

Newsy (Nov. 27, 2014) Tryptophan, a chemical found naturally in turkey meat, gets blamed for sleepiness after Thanksgiving meals. But science points to other culprits. Video provided by Newsy
Powered by NewsLook.com
Classic Hollywood Memorabilia Goes Under the Hammer

Classic Hollywood Memorabilia Goes Under the Hammer

Reuters - Entertainment Video Online (Nov. 26, 2014) The iconic piano from "Casablanca" and the Cowardly Lion suit from "The Wizard of Oz" fetch millions at auction. Sara Hemrajani reports. Video provided by Reuters
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


Plants & Animals

Earth & Climate

Fossils & Ruins

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