There are different variations of Omega 3 fatty acids. For instance, Avocados is rich in Omega 3 ALA which is considered not as effective as EPA and DHA.
>> Now, new research from the Intermountain Healthcare Heart Institute in Salt Lake City finds that higher EPA blood levels alone lowered the risk of major cardiac events and death in patients, while DHA blunted the cardiovascular benefits of EPA. Higher DHA levels at any level of EPA, worsened health outcomes.
>> [...] Based on these and other findings, we can still tell our patients to eat Omega-3 rich foods, but we should not be recommending them in pill form as supplements or even as combined (EPA + DHA) prescription products,” he said. “Our data adds further strength to the findings of the recent REDUCE-IT (2018) study that EPA-only prescription products reduce heart disease events.”
Fish is the only source of EPA and DHA.