Navigation Links
Evidence for omega 3 fats less conclusive than we thought, say experts

A study published online by the BMJ today doesn't find evidence of a clear benefit of omega 3 fats on health.

These findings do not rule out an important effect of omega 3 fats, but suggest that the evidence should be reviewed regularly, say the researchers.

Consumption of long chain omega 3 fatty acids, found in oily fish and fish oils, and a shorter chain omega 3, found in some plant oils, is thought to protect against heart disease. UK guidelines encourage the general public to eat more oily fish, and higher amounts are advised after a heart attack.

Researchers analysed 89 studies (48 randomised controlled trials and 41 cohort studies) to assess the health effects of long and short chain omega 3 fats on total mortality, cardiovascular events, cancer, and strokes.

Each study involved a treatment group and a control group and investigated the effect of omega 3 intake on health for at least six months. Differences in study quality were taken into account to identify and minimise bias.

Pooling the results showed no strong evidence that omega 3 fats have an effect on total mortality or combined cardiovascular events. The few studies at low risk of bias were more consistent, but they also showed no effect of omega 3 on total mortality or cardiovascular events.

When data on long chain omega 3 fats were analysed separately, total mortality and cardiovascular events were not reduced. No study showed increased risk of cancer or stroke with higher intake of omega 3, but there were too few events to rule out important effects.

Other recent reviews of omega 3 trials found that omega 3 fats decrease mortality, but the publication of a large contradictory trial has changed the overall picture. The authors cannot say exactly why the results of this trial differ from the other large studies in this field.

They therefore conclude that it is not clear whether long chain or short chain omega 3 fats (together or separat ely) reduce or increase total mortality, cardiovascular events, cancer, or strokes.

UK guidelines advising people to eat more oily fish should continue at present but the evidence should be reviewed regularly, say the authors. However, it is probably not appropriate to recommend a high intake of omega 3 fats for people who have angina but have not had a heart attack.

To understand the effects of omega 3 fats on health, we need more high quality randomised controlled trials of long duration that also report the associated harms, they conclude.

We are faced with a paradox, says Eric Brunner in an accompanying editorial. Health recommendations advise increased consumption of oily fish and fish oils. However, industrial fishing has depleted the world's fish stocks by some 90% since 1950, and rising fish prices reduce affordability particularly for people with low incomes.

Global production trends suggest that, although fish farming is expanding rapidly, we probably do not have a sustainable supply of long chain omega 3 fats, he warns.


'"/>

Source:BMJ-British Medical Journal


Related biology news :

1. Evidence of 600-million-year old fungi-algae symbiosis discovered in marine fossils
2. Researchers create pigs that produce heart-healthy omega-3 fatty acids
3. Innovative method for creating a human cytomegalovirus vaccine outlined
4. LIAI scientists make important finding on cytomegalovirus transmission
5. DNA conclusive yet still controversial, Carnegie Mellon professor says
6. Oceans more vulnerable to agricultural runoff than previously thought, study finds
7. Katrina floodwaters not as toxic to humans as previously thought, study says
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:10/4/2017)...  GCE Solutions, a global clinical research organization (CRO), announces the ... on October 4, 2017. Shadow is designed to assist medical writers ... 0070 of the European Medicines Agency (EMA) in meeting the requirements ... ... ...
(Date:6/23/2017)... ITHACA, N.Y. , June 23, 2017  IBM ... in dairy research, today announced a new collaboration using ... the chances that the global milk supply is impacted ... project, Cornell University has become the newest academic institution ... Chain, a food safety initiative that includes IBM Research, ...
(Date:5/6/2017)... -- RAM Group , Singaporean based technology ... biometric authentication based on a novel  quantum-state ... perform biometric authentication. These new sensors are based on a ... Group and its partners. This sensor will have widespread ... security. Ram Group is a next generation sensor ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... and LAGUNA HILLS, Calif. , Oct. ... Cancer Research, London (ICR) and University ... SKY92, SkylineDx,s prognostic tool to risk-stratify patients with multiple myeloma ... MUK nine . The University of Leeds ... partly funded by Myeloma UK, and ICR will perform the ...
(Date:10/11/2017)... ... October 11, 2017 , ... ... has granted orphan drug designation to SBT-100, its novel anti-STAT3 (Signal Transducer and ... of osteosarcoma. SBT-100 is able to cross the cell membrane and bind intracellular ...
(Date:10/10/2017)... ... October 10, 2017 , ... For ... has won a US2020 STEM Mentoring Award. Representatives of the FirstHand program travelled ... Volunteer Experience from US2020. , US2020’s mission is to change the trajectory of ...
(Date:10/10/2017)... Calif. , Oct. 10, 2017 SomaGenics ... from the NIH to develop RealSeq®-SC (Single Cell), expected ... for profiling small RNAs (including microRNAs) from single cells ... Program highlights the need to accelerate development of approaches ... "New techniques for measuring levels ...
Breaking Biology Technology: