If you have been working hard to make better choices in the kitchen — swapping out processed foods, reading labels carefully, choosing products marketed as cleaner and healthier — this post is important. Because some of what you think you know about cooking oils may not be accurate. And the gap between what the label says and what is actually in the bottle is wider than most people realize.
This is not a reason to feel defeated. It is a reason to get informed.
The Avocado Oil Problem
In 2026, researchers at UC Davis tested 54 processed food products — chips, mayonnaise, and salad dressings — that were labeled as made with avocado oil. What they found was striking: 89% of those products contained other oils. In most cases, the cheaper seed oils that health-conscious consumers were specifically trying to avoid.
The brands involved were ones that many people in the wellness community trusted and recommended — including Siete Foods, Boulder Canyon, Primal Kitchen, and Chosen Foods. I was among them. In a summer 2025 post about managing health through the warmer months, I specifically called out Siete, Jackson’s, and Boulder Canyon as better-for-you chip options made with cleaner oils. I stand behind the intention of that recommendation — I was pointing people toward what appeared to be a healthier alternative to conventional seed oil chips. But the UC Davis findings change the picture significantly, and I feel it is important to say so directly: if you purchased any of those brands based on my recommendation, I am sorry. You deserved better — and so did I.
The findings triggered a Texas Attorney General investigation and class action lawsuits against several major companies. Primal Kitchen responded with an official statement: “We source our avocado oil from trusted suppliers who confirm the oil’s integrity through independent, third-party laboratory testing. We are confident in our ingredients but continuously review our supply chain.” Founder Mark Sisson also responded personally, insisting Primal Kitchen uses 100% pure avocado oil. Siete Foods, Boulder Canyon, and Chosen Foods had not issued public statements at the time of writing.
It is worth noting, as the UC Davis researchers themselves acknowledge, that the brands may not have been the source of the problem. Avocado oil is expensive, relatively new to mainstream markets, and its supply chain is newer and far less standardized than other oils — creating significant opportunity for adulteration at the supplier level before the oil ever reaches a brand’s production facility. A company could genuinely believe it was using pure avocado oil without knowing it had already been diluted or substituted upstream.
That does not make the outcome acceptable. Consumers paid premium prices for a product they did not receive. But it illuminates a deeper problem: the integrity of the food supply — particularly in the oils category — is far less reliable than most people assume.
The Olive Oil Problem
Olive oil is one of the most corrupt food markets in the world. This is not hyperbole — it is a well-documented reality confirmed by researchers, investigative journalists, and regulatory bodies for decades. Studies have consistently found that the majority of olive oils sold globally — including many labeled as extra virgin — are adulterated with cheaper oils, sometimes the very seed oils consumers are trying to avoid. Regulatory bodies exist, but enforcement is weak, supply chains are long and complex, and the financial incentive to substitute cheaper oils is enormous.
The label on your olive oil bottle, however premium it appears, is unfortunately no guarantee of what is actually inside.
And adulteration is only part of the problem. Even a genuine, unadulterated olive oil loses its most valuable properties over time — and most grocery store olive oil is already old before it ever reaches the shelf. By the time it arrives in your kitchen, much of what made it worth buying may already be significantly diminished.
Why Freshness Is Everything: Understanding Oleocanthal
To understand why freshness matters so profoundly, it helps to understand what makes high-quality extra virgin olive oil genuinely extraordinary.
Oleocanthal is a naturally occurring phenolic compound found exclusively in freshly pressed extra virgin olive oil. Research has established that it possesses anti-inflammatory properties comparable to ibuprofen — working through similar biochemical pathways to reduce inflammatory markers in the body. For anyone managing chronic inflammation, metabolic health, or cardiovascular risk, this is a meaningful and well-researched property.
There is a simple and remarkable way to identify oleocanthal in an olive oil: taste it. A high-quality fresh extra virgin olive oil will produce a distinct peppery, almost burning sensation at the back of the throat. That sensation is oleocanthal activating specific receptors. Most people assume this means the oil is too strong or somehow off. In fact it means the exact opposite — it is a sign of exceptional quality and potency.
The challenge is that oleocanthal degrades over time. Every month an olive oil sits in a warehouse, on a shipping container, or on a grocery store shelf, its oleocanthal content diminishes. Refined olive oils, light olive oils, and oils that have been improperly stored or adulterated deliver a fraction of this benefit — or none at all. By the time a typical grocery store olive oil reaches your kitchen, much of what made it worth buying may already be gone.
This is why sourcing matters as much as purity. A genuine, unadulterated olive oil that is also fresh — pressed recently, stored properly, and delivered quickly from a source you can verify — is a fundamentally different product from what most people are buying.
The Butter Question
Cooking oils are not the only fat category where label claims deserve scrutiny.
Grass-fed butter has become a staple for health-conscious consumers — and for good reason. Butter from truly grass-fed cows has a meaningfully different nutritional profile, including higher levels of omega-3 fatty acids, conjugated linoleic acid, and fat-soluble vitamins. But not all grass-fed claims are equal.
Kerrygold, long considered a gold standard in this category, has faced significant scrutiny. An active class action lawsuit alleges that the company’s “100% grass-fed” labeling is misleading — because Irish dairy cows receive supplemental GMO grain feed during winter months when pasture grass is not available. Additionally, concerns about PFAS chemicals in Kerrygold’s packaging led to a recall in New York and California in 2023, though the packaging has since been updated.
For those seeking a genuinely reliable grass-fed butter, New Zealand sourced butter is worth considering. New Zealand’s climate allows for year-round pasture grazing — meaning grass-fed claims from that region are far more consistently accurate than claims from regions with cold winters.
The Complete List of Oils to Minimize or Avoid
The following oils are most strongly associated with chronic inflammation, oxidative damage, and metabolic dysfunction — and are worth minimizing or eliminating from your kitchen:
Canola oil — one of the most widely used and heavily processed oils in the food supply.
Soybean oil — the most consumed oil in the United States and the primary driver of omega-6 overload in the American diet.
Corn oil — extremely high in omega-6 and almost exclusively derived from GMO crops.
Cottonseed oil — produced from a fiber crop rather than a food crop, with a high risk of pesticide residue.
Sunflower oil — heavily refined and highly susceptible to oxidation.
Safflower oil — similar concerns to sunflower, with an unfavorable inflammatory fat profile.
Grapeseed oil — despite a wellness halo, extremely high in omega-6 and prone to oxidation and increased inflammatory markers.
Rice bran oil — often marketed as a high smoke point option, but highly refined and molecularly unstable under heat, producing toxic byproducts called aldehydes.
Peanut oil — technically a legume oil rather than a seed oil, but highly refined, high in omega-6, and worth minimizing.
Avocado oil products from processed food brands — until supply chain integrity issues are resolved and independent verification is widely available, these cannot be relied upon to contain what the label claims.
A note on sesame oil: cold-pressed sesame oil used sparingly as a finishing oil is generally considered acceptable — it has a more favorable antioxidant profile than the oils listed above. Refined sesame oil used for high-heat cooking is a different story and is best avoided.
All of these oils share a common problem: they are disproportionately high in omega-6 fatty acids. While omega-6 is essential in small amounts, the average American now consumes 15 to 20 times more omega-6 than omega-3 — a ratio strongly associated with chronic inflammation, insulin resistance, and metabolic disease. Most of these oils are also chemically unstable when heated, producing toxic byproducts that damage cells and drive oxidative stress.
Oils to Trust — A Practical Guide
For high-heat cooking: Grass-fed butter, ghee, beef tallow, and coconut oil are all excellent choices. These fats are stable at high temperatures, do not oxidize the way seed oils do, and have nourished human populations for millennia.
For finishing, dressing, and lower-heat cooking: A genuinely pure, fresh extra virgin olive oil — one you can verify is recent, properly sourced, and tested for both purity and oleocanthal content — is one of the most health-supportive fats available. Given the widespread adulteration in the olive oil market, sourcing directly from a producer you can trace is the most reliable approach.
What to Look For in a Quality Olive Oil
When sourcing olive oil, the following are meaningful indicators of genuine quality:
A clearly stated harvest date — not just a best-by date, but the date the olives were actually pressed. The shorter the time between harvest and your kitchen, the better. A producer who tests for both purity and polyphenol content, including oleocanthal. A distinct peppery finish when you taste it — the throat sensation that indicates meaningful oleocanthal content. Single-origin sourcing from a producer you can trace directly. The more steps between the olive tree and your bottle, the more opportunity for compromise.
The Bottom Line
The avocado oil situation is a symptom of a larger problem: a food supply where premium labeling and premium pricing do not always correspond to premium contents. This is particularly true in the oils category, where adulteration is financially motivated, technically straightforward, and historically rampant — in avocado oil, in olive oil, and in products that claim to contain them.
The answer is not to feel paralyzed or betrayed. It is to get specific. To know where your food comes from. To source from producers you can verify and trace. And to work with a guide who is watching the research, staying current, and willing to update their recommendations when the evidence changes.
Your body deserves the real thing. And the real thing — genuinely fresh, genuinely pure, genuinely potent — is worth seeking out.
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