Free entry from The Complete Supplement Guide
Omega-9 Fatty Acids (Oleic Acid)
Graded Strong · Foundational Health · free to read
This is the fatty acid that makes extra virgin olive oil one of the most health-supporting foods on the planet.
The dose range, the form that actually absorbs, the purity red flags and what not to stack it with are in the guide.
Get The Complete Supplement Guide →Last reviewed September 2026
The verdict
Is Omega-9 Fatty Acids worth taking?
This is the fatty acid that makes extra virgin olive oil one of the most health-supporting foods on the planet. Food wins here unambiguously. Two to four tablespoons of quality EVOO daily, avocado regularly, and a handful of macadamia nuts or almonds covers omega-9 without any supplementation. Buy the best olive oil you can afford. A genuine EVOO should have a peppery, slightly bitter finish. If it tastes flat, it has probably been adulterated.
What it does
What Omega-9 Fatty Acids does in the body
Cardiovascular protection, LDL cholesterol reduction, HDL support, insulin sensitivity, anti-inflammatory activity, brain health, and skin integrity. Oleic acid is the dominant fat in olive oil, avocado, and macadamia nuts. Populations with the highest oleic acid intake consistently demonstrate the lowest rates of cardiovascular disease, cognitive decline, and metabolic dysfunction of any dietary pattern studied globally.
The evidence
What the research actually shows
The cardiovascular and metabolic benefits of oleic acid are among the most robustly evidenced in nutritional epidemiology. The PREDIMED trial demonstrated that high extra virgin olive oil intake significantly reduced cardiovascular events. Evidence for LDL oxidation reduction, insulin sensitivity improvement, and anti- inflammatory activity via oleocanthal is consistent and well replicated.
Food first
Getting Omega-9 Fatty Acids from food
Extra virgin olive oil, avocado, macadamia nuts, almonds, and olives are the primary food sources. This is one of the few entries in this guide where food unambiguously wins over supplementation.
From the kitchen
A chef's note on Omega-9 Fatty Acids
I use extra virgin olive oil as the foundation of my kitchen. It goes on everything that is not going into high heat. My clients notice the difference in flavor, in digestion, and over time in how they feel. Buy the best olive oil you can afford, store it in a cool dark place, and use it generously every day.
What the guide adds
The part that is not on this page
Everything above is the assessment. What the guide adds for Omega-9 Fatty Acids is the protocol:
- Optimal Form
- Dose Range
- Bioavailability
- Purity Red Flags
- Stack With / Avoid
147 entries across nine categories, every one graded against the clinical literature the same way.
About the author
Who graded this
Daniel Edlund is a Le Cordon Bleu-trained private chef in Los Angeles, a certified personal trainer and strength coach, and an internationally licensed massage therapist. Thirty years of strength training and fifteen years cooking in private estate kitchens. He is the author of The Complete Supplement Guide, which grades 147 entries against the clinical literature, and of The EASY Way to Organic Cooking, first published in 2013.
This page is information, not medical advice. Supplements interact with prescription medication and with each other, and the right answer depends on your own bloodwork and history. Talk to your doctor before starting anything, particularly if you are pregnant, nursing, managing a health condition, or already taking medication.
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