Why Avoiding Seed Oils Protects You Far More Than Going Glyphosate-Free

Why Seed Oil Aldehydes Pose a Much Greater Toxic Exposure Than Glyphosate

If you’re trying to get healthier, you probably want to know where to focus your food efforts. Should you spend extra on organic to avoid glyphosate? Or avoid seed oils? Which change will actually protect your health the most?

It’s easy to say this or that is bad for us. What’s hard — and this is the reason nobody else has done it, as far as I know — is to build a hierarchy of bad so people can tell what really matters most.

Without that hierarchy, everything sounds equally dangerous, and the result is paralysis. When you don’t know where to start, you might not start at all.

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That’s why I’ve spent years sorting through the evidence — not to make another list of “bad” foods, but to show what’s worst, what’s secondary, and what’s minor.

And when it comes to choosing between glyphosate-free and seed-oil-free, the science is remarkably clear: Eliminating seed oils spares your cells from tens of thousands of times more toxic exposure than going glyphosate-free.

That’s because “seed oil–free” and “glyphosate-free” don’t address the same kind of threat. They target completely different categories of exposure, and one of them dwarfs the other by several orders of magnitude in real-world risk.

A Simple Way to Picture It

Imagine a 75,000-seat stadium.

Glyphosate exposure from oatmeal is like one lonely fan sitting in that entire arena. The aldehydes that form when seed oils are heated (the compounds your cells actually have to neutralize every time you eat fried or processed foods) fill three whole stadiums, with people spilling out onto the field. 

That’s not an exaggeration. It’s what the chemistry shows.

If we want to build a meaningful hierarchy of bad, that’s the kind of difference we’re looking for — not small variations in lab data, but orders of magnitude in real-world exposure.

This is where the concept of toxic potential comes in.

Both glyphosate and aldehydes have measurable toxicity in the lab. But what determines whether they can hurt you is how much you’re actually exposed to in daily life. And that’s where the comparison becomes staggering: the aldehydes from heated seed oils deliver exposures that are tens of thousands of times higher than anything you’d get from pesticide residues.

So if you’ve been wondering where to start on your “eat healthy food” journey, this is it.

Crunching The Numbers on Seed Oils Versus Glyphosate

If you’re the kind of person who likes to see the math, here it is.

When researchers analyze real-world foods, they measure exactly how much of each compound people are actually exposed to. And when you compare those measurements to the concentrations known to harm cells, the scale of difference between aldehydes and glyphosate jumps off the page.

Here’s how the comparison looks when we translate it into lab measurements:

This table shows that, gram for gram, aldehydes are FAR more toxic than glyphosate, and their concentration in many common foods is also higher. 

So while both substances have toxicity in principle, only the aldehydes routinely reach levels that matter inside the human body.

I used oatmeal as the example because it’s one of the foods with the highest concentration of glyphosate. Healthier foods like broccoli, cheese, and meats come out below the threshold of detection, meaning they may contain zero, or at least not enough for testing to measure.

The math is simple and empowering. Your choice of cooking oil can protect you thousands of times more than the “glyphosate-free” label ever will.

Why you might see higher numbers for glyphosate than what’s in the chart above.

If you search online for glyphosate levels in food, you’ll find claims that residues average 1–2 mg/kg or even reach 18 mg/kg. Those figures come not from finished foods, but rather from broad agricultural surveys that combine dozens of food categories, including some that humans don’t eat, like raw crop samples, even animal feeds. The processing steps often eliminate much of the glyphosate. Before we eat them, oats are washed, steamed, and stripped of their outer hulls — all steps that remove much of the residue. That’s why finished oatmeal typically measures around 0.7 mg/kg, not the multi-ppm levels reported in raw grain surveys.

That’s why the data for finished products,  like oatmeal, tell a different story. Independent lab testing (including FDA and EWG studies) finds most finished oat products contain 0.3–1.3 mg/kg, with an average around 0.7 mg/kg. That’s roughly a thousand times lower than the doses used in lab experiments to produce cell damage. In other words, the scary-sounding numbers you might see online usually describe concentrated raw grains or animal feed, not the cooked oatmeal you eat for breakfast.

So why does the discourse around glyphosate sound scarier than that?

It’s usually not because people are trying to mislead anyone. More likely, they see two numbers — a low one from FDA/EFSA monitoring and a higher one from a broad residue survey — and, out of healthy skepticism (“maybe industry is lowballing it”), they lean toward the higher number. That’s human. But in this case, the gap isn’t about industry spin; it’s about which stage of the food was tested.

And here’s another key point to keep in mind:

Even if we take one of those higher, raw-grain numbers — say 18 mg/kg — and pretend your bowl of oatmeal actually had that much, your exposure would still be hundreds of times below the concentrations that harmed cells in lab studies.

A quick reality check:

• 18 mg/kg in oats
• Eat 100 g? That’s 1.8 mg total
• Spread through ~40 L of body water? 0.045 mg/L
• Lab toxicity shows up around 17 mg/L
• 0.045 ÷ 17? 1/375

Even using the “scary” number, you’re still ~300–400× below toxicity. That’s the opposite of what we see with seed-oil aldehydes, where real-world food levels shoot past cellular toxicity ranges.

So while the glyphosate conversation has been amplified, the aldehyde story has barely been told.

Why Medicine Overlooks Toxic Aldehydes

You’d think such a potent toxin would be headline news.
But the reason it’s not widely known is that these data live in a different scientific universe.

The world’s preeminent expert in seed oil aldehydes is Dr. Martin Grootveld. He’s been publishing on this subject for decades, trying to get the word out. So why do leading cardiologists and nutritionists seem not to know about this? Because in spite of Dr. Grootveld’s dominance in his field, at the end of the day, he is a lipid-chemistry expert, not a medical doctor. And he publishes his work in journals that doctors do not read. Meanwhile, glyphosate gets constant attention because it’s tracked by the EPA and discussed in environmental-health circles.

This asymmetry leaves both the public and the medical profession with a distorted picture: they worry about parts-per-billion of a weak herbicide but ignore milligrams-per-serving of highly reactive lipid oxidation products.

I think another part of the problem is that it’s hard to get our heads wrapped around the idea that organic foods can contain meaningful amounts of toxins.

Key Fact: Organic Does Not Mean Toxin-Free

Organic food labels are designed to protect us from intentionally added chemicals and soil contamination, not from the chemistry of food processing. The organic label tells you about how a food was grown and that no harmful chemicals were added intentionally, but it does not tell you about what happens when it’s cooked.

The Empowering Takeaway

What Truly Matters Most

Once you understand where the real danger lies, your choices become simpler—not harder.

You don’t need to memorize chemical names or buy foods emblazoned with every possible “free of” symbol. You just need to know which habits actually move the needle for your health. The single most powerful one is this:

Memorize the eight toxic seed oils and start cutting down your consumption.

That one decision will start to relieve your body of the chronic, meal-by-meal exposure to reactive molecules that damage cell membranes, mitochondrial enzymes, and DNA itself. Every packaged product containing refined seed oil adds to that invisible burden. Every home-made meal containing real-food fats instead gives your cells a break to recover.

Buying organic still has value. It protects ecosystems and keeps farm workers healthier. But if your goal is personal health, the first step isn’t going organic; it’s getting oxidation-savvy. Skip the seed oils, and you’ve already sidestepped 90% of modern food toxicity.

References for Toxicity Comparison Table

Esterbauer, H.; Schaur, R. J.; Zollner, H. (1991). “Chemistry and biochemistry of 4-hydroxynonenal, malonaldehyde and related aldehydes.” Free Radical Biology & Medicine, 11(1): 81-128.

Doorn, J. A.; Petersen, D. R. (2004). “Reactions of 4-hydroxynonenal with proteins and cellular targets.” Free Radical Biology & Medicine, 37(7): 937-945.

Minekura, H. et al. (2001). “4-Hydroxy-2-nonenal is a powerful endogenous inhibitor of NF-?B activation in endothelial cells.” Biochemical and Biophysical Research Communications, 285(4): 960-966.

Mesnage, R.,?et al. (2021). “Determination of glyphosate and AMPA in oat products for the certification of reference materials.” Food Chemistry, 365: 130454. (PMC) PMC

Environmental Working Group (EWG). (2018). “Breakfast With a Dose of Roundup? Glyphosate in popular oat-based foods.” EWG Food & You research. EWG+1

Environmental Working Group (EWG). (2019). “Glyphosate Contamination in Food Goes Far Beyond Oat Products.” EWG News & Insights. EWG

NDSU Extension. (2023). “Glyphosate on Potatoes.” North Dakota State University Extension Publication. ndsu.edu