Omega-3 Fish Oil vs Fatty15 (C15:0 / Pentadecanoic Acid)
Both graded for Heart & Cardiovascular
For their shared cardiovascular goal, reach for omega-3 fish oil first: its heart claim is Grade A, backed by a Cochrane review of 86 RCTs and the REDUCE-IT trial, whereas Fatty15 (C15:0) is Grade C across the board — and the independent 2026 CARDIA/ARIC analysis of 7,000+ people found no association with cardiac events and no causal effect in Mendelian randomization. It isn't a close call on evidence: omega-3's "essential" status is long-established, while Fatty15's essentiality claim rests almost entirely on papers by its own maker's founders, and the National Academies does not recognize C15:0 as essential. Omega-3 also carries a Grade B case for brain/cognitive support that Fatty15 doesn't target at all. Fatty15 is really only for someone who wants to experiment with a novel compound knowing the science is thin and largely industry-generated — not as a substitute for a heart-health intervention.
Omega-3 Fish Oil
EPA and DHA from fish oil have strong cardiovascular and cognitive evidence — but dose, form, and freshness matter more than most labels suggest.
Reduces cardiovascular risk markers (triglycerides, inflammation)
Most guidelines suggest 250-500 mg combined EPA+DHA/day for general health; 2-4 g/day for triglyceride reduction (under medical supervision).
Heart & Cardiovascular, Brain & Cognitive
Fatty15 (C15:0 / Pentadecanoic Acid)
Marketed as the first essential fatty acid discovered since omega-3 — the evidence for that claim comes almost entirely from the company that sells it.
Qualifies as a newly discovered essential fatty acid
Fatty15's own product delivers 100 mg/day of purified C15:0. The only published RCT to test the ingredient in isolation used 200 mg/day for 12 weeks. There's no established therapeutic range, because there's no scientific consensus that supplementation is needed at all.
Heart & Cardiovascular
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