what the seed oil debate is missing

More than fatty acids; What the Seed Oil Debate Keeps Missing

There’s no shortage of opinion about seed oils—but much of it circles the same handful of perhaps the least important claims. My purpose in writing articles is to present a perspective not commonly seen or heard—one that brings light to the places where things have been left vague, whether by design or oversight, and this topic is no exception. This is not to present a list of what to avoid. It also doesn't take the side most might anticipate. Instead, it’s an invitation to have the conversation that the ongoing debate keeps missing. Instead of oversimplifying the complexity of this matter, my hope is that through this lens, the one I use when determining which ingredients will go into the foods I formulate, the more critical things can begin to be discussed.

Beyond Fatty Acid Ratios

Much of the debate around seed oils focuses on omega-6 versus omega-3 fatty acid ratios. While relevant in certain contexts, this narrow focus often misses a deeper—and arguably more urgent—conversation: the totality of what happens to an ingredient throughout its processing lifecycle and how that impacts, well, everything. From herbicide exposure to solvent extraction, chemical refining, and packaging—all of these factors impact oil, in general, in ways that extend far beyond its fatty acid profile. While relevant in certain contexts, the fixation on omega ratios often misses the more urgent conversation: the totality of what happens to an ingredient across its entire processing lifecycle—and how that affects the body. This includes the structural integrity and bioavailability of omega fatty acids, which are notoriously vulnerable to heat, solvents, and oxidation. So while the debate over “good” and “bad” fats continues, the more essential question is whether these fats are still functional—or even safe—by the time they reach the plate. It seems to me that the same arguments keep repeating—not because they haven’t been discussed enough, but because the conversation has yet to center on the actual issue. That begins with a broader, systems-level understanding of everything oil is subjected to before it ever reaches a plate—and why that matters for both immediate and long-term health.

Should There Be a Real Concern About Seed Oils?

A Product Developer’s Take on What’s Left Out of the Conversation

When I assess an ingredient for use in a product, I want to know everything. Not just the macronutrients or the labeling claims—but every step of the journey from seed to finished raw material. I want to understand exactly what that ingredient went through before it shows up in a factory, ready to be used.

Most consumers have no idea how many steps that can include. And when companies say something is “minimally processed,” they’re often referring to the final product mix. In reality, many ingredients are processed multiple times long before they ever make it into that formulation—often in the presence of carriers, preservatives, or processing agents that never show up on the nutrition label.

As a formulator, whose primary goal is developing products I would feed my own family, I want transparency at every level. If I’m going to favor one oil over another, I need to know those same process details for all the options available to me. This article outlines what I consider in order to make that decision.

Let’s start with canola oil—and expand from there.

From Rapeseed to Canola oil: Step by step

Rapeseed (Brassica napus) is a high-oil-content plant cultivated for its seeds. Traditional rapeseed oil contained high levels of erucic acid, which can be toxic in large amounts. In the 1970s, Canadian scientists developed a low-erucic acid variety through conventional breeding—not genetic engineering—to reduce this toxicity. The result was branded “Canola,” short for CANadian Oil, Low Acid.

Now, I consider this part of the “process,” because nature didn’t make the seed this way. As soon as human intervention alters a plant at the genetic or varietal level, I consider that to be processing step one.

Further, today, over 90% of canola grown in the U.S. is now also genetically engineered to tolerate herbicides like glyphosate and glufosinate. This allows the crop to be sprayed repeatedly, killing weeds without harming the plant itself. These chemicals are harsh by design—so the seed is re-coded to withstand what would otherwise kill it. That’s processing step two.

Before the seed is even in the ground, it has already been manipulated twice. By my definition as a formulator (and a consumer), that matters.

The Manufacturing Process: From Rapeseed to Oil

After the crop has grown and the seeds are harvested, the production of canola oil moves through the following steps:

• Seed Cleaning and Conditioning: Seeds are cleaned and heated to prepare for oil extraction. The cleaning is not with water because that would add moisture and compromise oil yield. The cleaning process is more of a sieving and separating process. Dust, stems, small stones, and hulls are removed through de-hulling, screens, and/or by air aspirators. In other words, the dust gets blown off, but the pesticide and fumigation residue remains to all or some extent.

• Mechanical Pressing: Initial oil extraction is performed using screw presses, recovering about 60% of the oil.

• Solvent Extraction: The remaining oil is extracted using hexane, a petroleum-based solvent.

• Refining Process and More Ingredients:

• Degumming: Removes phospholipids using phosphoric acid.

• Neutralization: Free fatty acids are removed using sodium hydroxide.

• Bleaching: Removes color and pigments using activated clays.

• Deodorization: High-temperature steam (>200°C) removes odors and volatiles, potentially generating trans fats and oxidation byproducts.

Before moving on, it’s important to emphasize that during seed cleaning, residues from pesticides and herbicides can remain—even after dust and debris are removed. There is a long list of issues with this, which I will save for another time. This is a little bit, simply for context:

Glyphosate Residue and the Gut Microbiome

Glyphosate targets the shikimate pathway that many gut bacteria have. This interference can disrupt the gut microbiome by affecting how certain microbes produce essential nutrients and interact with the immune system:

• Inhibition of beneficial microbes like Lactobacillus and Bifidobacterium

• Proliferation of resistant strains such as Clostridium and Salmonella

• Potential dysbiosis and immune system implications

Studies have shown that even low doses of glyphosate can alter gut microbial composition and function. While significant advances have been made in gut health research, we still understand relatively little about the full complexity of the human microbiome. As the science continues to evolve, more conclusive data will emerge—but we already know enough to recognize that the relationship between microbial activity and biological signaling is deeply interwoven, and that disruption at any level can carry both immediate and cumulative health implications.

Herbicide-resistant crops, particularly genetically modified (GM) canola, are widespread in modern agriculture. While the inserted genes themselves are not yet known to be inherently harmful to humans, their purpose—to allow extensive herbicide application—raises critical questions about how these chemicals may impact human health, including but not limited to the gut microbiome.

Now, returning to the bigger picture: this is a refined oil process. While it's the standard for most seed oils, it’s not exclusive to them—refining can apply to other oils as well, depending on how they’re manufactured. One more important detail: when you see the term virgin, it generally means unrefined. That means the multi-step chemical refining process outlined above did not apply.

Now, let's take a closer look at the most common oils in product manufacturing, both virgin and refined, and the processing steps and chemicals of each from seed to shelf:

A Comparative Look: seed Oils, Olive Oil, Coconut Oil, and Tallow

To understand how seed oils differ from traditional fats, it's essential to examine the manufacturing methods and exposure risks associated with other commonly used fats. In the absence of nuance, the discussion risks being driven more by reaction than by reason.

Oil/Fat Type	GMO Status	Extraction Method	Refining Process	Chemical Exposure	Packaging Concerns	Nutrient Retention	Notes
Canola Oil	Typically GMO (over 90% of US crop is genetically modified unless certified organic or Non-GMO Project verified)	Mechanical + Solvent (Hexane)	Full refining (degumming, neutralizing, bleaching, deodorizing)	Hexane, sodium hydroxide, BPA	Commonly in plastic bottles	Low (due to heat/refining)	High efficiency, but high processing and residue exposure
Sunflower Oil (Refined)	Often Non-GMO (check source)	Mechanical or solvent extraction (hexane)	Full refining (degumming, neutralizing, bleaching, deodorizing)	Hexane, sodium hydroxide, bleaching clays	Plastic bottles common; light-sensitive	Low; vitamin E may be stripped during refining	High in omega-6; refined versions prone to oxidation
Safflower Oil (Refined)	Often Non-GMO (some hybrids exist)	Solvent extraction or expeller-pressed	Full refining, may include bleaching and deodorizing	Hexane, sodium hydroxide	Plastic packaging common; light protection varies	Low due to processing	Often used in high-heat applications; high PUFA content
Soybean Oil (Refined)	Typically GMO (unless organic or verified non-GMO)	Solvent extraction (hexane) + mechanical pressing	Degummed, neutralized, bleached, deodorized	Hexane, sodium hydroxide, phosphoric acid	Usually plastic; light and air-sensitive	Low; oxidative stability is poor	Highly processed and common in processed foods; high in omega-6
Corn Oil (Refined)	Typically GMO (unless organic or verified non-GMO)	Solvent extraction (hexane) + refining	Degumming, alkali neutralization, bleaching, deodorization	Hexane, sodium hydroxide, citric acid	Plastic packaging common; often heat-treated	Low; tocopherols often reduced	High omega-6, widely used in industrial food products
Grapeseed Oil (Refined)	Non-GMO	Solvent extraction (often hexane)	Bleached and deodorized to neutralize flavor	Hexane, bleaching clays	Often bottled in plastic or clear glass	Very low; natural antioxidants removed	Oxidizes quickly due to high PUFA content; minimal residual nutrition
Olive Oil (Extra Virgin)	Non-GMO	Cold-pressed mechanical	None or light filtration	None (if unrefined)	Often glass bottles	High (polyphenols, oleocanthal)	Minimal processing, considered microbiome-safe
Olive Oil (Refined)	Non-GMO	Heat and filtration; lower-grade oils may be chemically refined	May involve neutralization, bleaching, and deodorization	Rare, but some industrial oils may be refined	Sometimes plastic, increasingly BPA-free	Lower than EVOO	Quality varies; best when kept cool before packaging
Avocado Oil (Virgin)	Non-GMO	Cold-pressed or centrifuged	Minimal, if unrefined	None	Often glass or BPA-free plastic	High in monounsaturates and antioxidants	Cold processing preserves integrity
Avocado Oil (Refined)	Non-GMO	Often expeller-pressed and filtered; some deodorized	Yes – may include bleaching/deodorization	Possible oxidation	Plastic bottles more common; BPA-free options vary	Lower antioxidant content	Quality varies; temperature before packaging is key
Coconut Oil	Non-GMO	Cold-pressed (virgin) or expeller	May be refined (RBD)	None (virgin), some (refined)	Often glass or BPA-free	High in unrefined, moderate in RBD	Stable saturated fat, low oxidation risk
Coconut Oil (Refined)	Non-GMO	Expeller-pressed or solvent-extracted from copra	RBD: Refined, bleached, deodorized	May include bleaching clays and deodorization byproducts	Commonly in plastic or BPA-free jars	Lower than virgin coconut oil; some loss of antioxidants	Highly stable due to saturated fats; less flavor/aroma than virgin
Tallow (Beef Fat)	Depends on animal feed; typically not GMO itself	Rendered from suet (dry or wet heat)	Minimal (strain/filter)	None	Stored in glass/jars	High in fat-soluble vitamins (A, D, K2)	Traditional fat, low oxidative stress, no solvents

Note: If you choose Tallow, watch your sources carefully. As this is becoming a more popular option, you can be assured that the supply will become harder to navigate. Keep it local and grass fed from Regenerative Farms for the best way to ensure the quality remains intact.

Still More Processing to Consider

Plastic Use and Cooling in Refined Oils

For refined oils like canola, olive or avocado, especially those packaged in plastic, the following considerations should apply:

• Plastic Use: Most plastic bottles used for edible oils today are BPA-free, particularly when labeled as such. However, not all suppliers disclose this.

• Cooling Process: Refined oils must be cooled before bottling, especially if plastic is used, to prevent chemical leaching. Responsible manufacturers cool oils to safe temperatures (often below 40°C or 104°F) before packaging to minimize oxidation and interaction with packaging materials. Not all manufacturers cool the oils in safe containers, some cool it down in plastic before bottling in plastic. This is one of the reasons there is benefits of knowing who is making your food.

Packaging Concerns: BPA and Oil Storage

Storing oils in plastic containers raises concerns about chemical leaching. Bisphenol A (BPA), a known endocrine disruptor, can migrate into oils—especially under high-heat conditions or during prolonged storage. Because oils are lipophilic, they readily absorb such contaminants, posing potential health risks.

It’s also important to note that once oils are stabilized and packaged, they’re considered “shelf stable”—meaning they’re typically not shipped or stored under temperature-controlled conditions. As a result, they may be exposed to heat during transit or warehousing, making BPA leaching an ongoing concern.

The Gap in Human Studies

Despite widespread exposure, human studies on the health effects of glyphosate, solvent residues, and BPA are limited. Challenges include:

• Ethical constraints:
  There’s a common but critical misunderstanding that if something is on the shelf, it has been tested in humans. In reality, exposing humans to toxins in controlled trials is not only unethical—it’s impermissible. Substances like glyphosate, BPA, or industrial solvents cannot be tested this way. Safety assessments instead rely on animal models, in vitro studies, and observational data—none of which fully reflect real-world human exposure or account for bioaccumulation, the process by which small, repeated exposures can build up in tissues over time, potentially amplifying toxic effects.

• Industry resistance:
  Financial and political interests can limit independent research. Much of the safety data is industry-funded, raising concerns about transparency, bias, and incomplete risk evaluation.

• Complexity of exposure:
  Humans are exposed to many chemicals simultaneously, making it difficult to isolate the effects of any one compound. Observational studies exist but are limited by confounding factors and cannot definitively establish causation.

As a result, the absence of human data is not evidence of safety—it reflects the ethical and scientific constraints of our current systems. And that distinction matters.

Socioeconomic Considerations

To be clear, this isn't about criticizing what's accessible, though I would argue it’s fair to critique what has been made to be accessible. The oils we're talking about are widely used because they’re cheap, scalable, and engineered to fit into a system optimized for shelf life and efficiency. And for a lot of people, they’re the only realistic option.

Pointing out how something is made—where it comes from, what it’s been exposed to, and how it changes along the way—isn’t a judgment. It’s a call to awareness. This article is written from my perspective as a formulator—someone who works directly with raw materials and systems. It’s about understanding how those systems shape our choices and how they impact human health. It’s both.

It’s also written from my perspective as a consumer advocate. I formulate from that posture first. As a product developer, I understand the pressure of cost of goods. As a woman who was a single mom, I also understand the cost of feeding a family on a limited income. That perspective isn’t lost on me—it informs a significant amount of what I do.

When the public is informed, demand begins to shift. And when demand shifts, supply chains evolve. We’ve already seen this in action: just two years ago, there were maybe one or two brands offering tortilla chips cooked in avocado oil. Now, you’ll find six to eight brands using it—and the prices are going down. Why? Because awareness creates pressure, and pressure drives accessible change.

That’s also why I approach these topics the way I do. My background in the food industry has shown me firsthand: supply chains are driven by consumerism. When consumer behavior changes, manufacturers and suppliers respond. That’s how change moves from concept to reality, from niche to normalized. And when industry follows, change becomes something everyone can access—not just those with privilege or proximity to premium options.

immediate application and Next steps

My choice of which oil to use isn’t based on emotion—it’s rooted in scientific reasoning. I look for what carries the fewest unknowns, assumptions, synthetic chemicals, and processing agents—and offers the greatest health benefit in a form as close to nature as possible. I personally rotate between virgin organic coconut oil, virgin organic olive oil, and regenerative tallow primarily. In manufacturing, there are additional factors that must be considered—many of which fall outside the scope of this article—but those are the criteria I use to determine which of the three to incorporate into a given formulation.

For those seeking direction, feel free to consider the conclusion I’ve come to: when possible, choose cold-pressed, organic, or non-GMO oils packaged in glass or BPA-free containers. Support local and regenerative farming practices that minimize chemical inputs whenever you can. And when it comes to packaged foods—like chips, salad dressings, or snacks—look for products made with those same oils, as best you’re able.

As is always my suggestion, try not to become dogmatic about choices like these, and don’t fear the moments when ideal options aren’t available. This is a process—not perfection. Food is meant to be a gift, something to be shared and enjoyed at the table with others. And if there’s one thing we can all agree on, let it be this: we will not be divided at the table over what’s on it.

Conclusion

This isn’t just an article—it’s a reflection of what I’ve witnessed behind the scenes and what I want the people I care about to understand. My hope is that it empowers better questions, more informed decisions, and ultimately, a healthier, more transparent system.

The entire production chain of seed oils—from crop to shelf—raises health concerns that deserve closer attention. From genetically modified crops and heavy herbicide use to solvent-based extraction, high-heat refining, and potential BPA leaching from packaging, each step can introduce compounds with biological consequences.

Omega fatty acid ratios are still relevant and worth discussing, but focusing solely on fat composition misses the larger picture I’m presenting: the cumulative toxic burden introduced through industrial processing—and whether the fats themselves remain bioavailable or beneficial by the time they reach the human body. If seed and refined oils continue to deliver persistent, bioaccumulative chemicals, we risk overlooking a more urgent and addressable health opportunity.

This isn’t about demonizing fat—it’s about asking better questions about the systems behind these ingredients, to ensure that once they reach the body, they’re still capable of doing what they were originally intended to do. Not all seeds—or oils—are created or processed equally, and within that distinction lie the real consequences for human health worth discussing.

Additional Sources:

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