December 24 (HealthDay News) -- Consuming fish oil appears to reduce the chance of death from heart problems, but it may not help those with heart rhythm problems, a new analysis shows.

The conclusions are based on a Canadian review of dozens of fish oil studies involving more than 30,000 people. The study, by a team at the University of Alberta, in Edmonton, was published in the online edition of BMJ.

Eleven studies reported fish oil supplements helping reduce deaths from heart problems by 20 percent; however, none of the studies were able to determine the optimal dose or formulation of fish oil.

Six studies reported no benefit of fish oil in preventing sudden cardiac death. Three studies of whether fish oil supplements helped reduce the need for implantable cardiac defibrillators showed a neutral effect.

An accompanying editorial calls for more funding on the fish oil issue, not only to determine whether a health benefit truly exists, but also to protect the world's marine life.

SOURCE: BMJ, news release, Dec. 23, 2008