Episode

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You've Been LIED TO About Seed Oils! | Educational Video | Biolayne

Layne Norton

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TL;DR

The four things you'd lose by not watching

3 items

TL;DR

The four things you'd lose by not watching

3 items

A new study compared 30g/day soybean oil (high linoleic acid) vs. palm oil (high saturated fat) and found no differences in inflammatory markers or oxidized LDL, directly contradicting claims that seed oils are inflammatory.

Layne Norton explains that LDL oxidation occurs primarily in the artery wall (endothelium), not in the plasma, and is driven by LDL particle concentration—which rises with saturated fat intake, not polyunsaturated fat.

Therefore, when substituting seed oils for saturated fat, the effect on inflammation, cardiovascular disease, insulin sensitivity, and liver fat is either neutral or beneficial, with saturated fat posing the greater risk.

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Personal practice updates, fresh positions, predictions

2 items

Seed oil consumption does not increase inflammatory markers or oxidized LDL

early segment

A recent trial comparing 30 g/day soybean oil versus 30 g/day palm oil found no difference in inflammatory biomarkers or oxidized LDL, debunking the linoleic acid → arachidonic acid → prostaglandin pathway as a driver of inflammation in vivo.

Why this matters: This directly challenges prominent anti-seed-oil influencers (e.g., Paul Saladino) who claim linoleic acid is pro-inflammatory and raises oxidized LDL. The study adds to a body of evidence that seed oils are neutral or beneficial when replacing saturated fat.

Background

The anti-seed-oil movement argues that linoleic acid is converted to arachidonic acid, which is then turned into inflammatory prostaglandins, making seed oils supposedly inflammatory. Saladino also asserts that polyunsaturated fats increase oxidized LDL, a risk marker for heart disease. However, multiple feeding studies have already shown that high seed oil intake does not elevate inflammatory markers or arachidonic acid in humans.

Layne Norton highlights a new study where participants consumed 30 grams per day of soybean oil (rich in linoleic acid) or palm oil (rich in saturated fat). The soybean oil group ingested far more polyunsaturated fat, yet showed no rise in inflammatory markers or oxidized LDL compared to the palm oil group. This adds to a growing literature that the theoretical conversion of linoleic acid to arachidonic acid does not meaningfully affect systemic inflammation because the enzymatic pathways are tightly regulated and do not simply track substrate availability. Norton points out that oxidized LDL is not produced primarily in the blood—where antioxidants protect it—but in the artery wall after LDL particles penetrate and get retained. Once trapped in the endothelium, the apoB particle is enzymatically modified, which triggers local oxidation and inflammation. Because LDL penetration is concentration-dependent and saturated fat raises LDL cholesterol levels, a diet high in saturated fat is actually the bigger driver of oxidized LDL. Thus, the argument that seed oils are inflammatory or increase oxidized LDL fails both direct measurement and mechanistic scrutiny.

When you actually give high amounts of seed oils, they don't increase inflammatory markers and they don't increase arachidonic acid.

Also said

“They looked at various inflammatory markers and they basically saw no difference. They also saw no difference in oxidized LDL.”— Summarizes the primary null findings of the study.

Oxidized LDL is primarily driven by LDL particle concentration in the endothelium, not by fat type oxidation in plasma

mid-segment

LDL oxidation occurs in the artery wall after LDL particles are retained, and the rate of retention is concentration-driven; saturated fat raises LDL concentrations, making it a more potent driver of oxidized LDL than polyunsaturated fats.

Why this matters: This mechanistic clarification counters the simplistic claim that because polyunsaturated fats are more prone to oxidation in a test tube, they must increase oxidized LDL in the body. It reframes the debate around LDL particle number rather than fat unsaturation.

Background

Many critics of seed oils claim that polyunsaturated fatty acids are inherently dangerous because they oxidize easily, leading to higher levels of oxidized LDL and cardiovascular disease. This view is popularized by figures like Paul Saladino.

Norton walks through the biology: LDL does not get oxidized in the blood because plasma is rich in antioxidants. Instead, LDL particles penetrate the endothelium and become trapped in the intima, where they can be retained for days or weeks. Once there, enzymatic modification of the apoB particle attracts inflammation and oxidation. Some of that oxidized LDL can later leak back into the bloodstream, which is why higher circulating oxidized LDL correlates with heart disease—but it is a downstream marker, not the initiating cause. The critical step is the penetration and retention of LDL particles, which is a concentration-dependent process. Diets high in saturated fat increase the number of LDL particles in the blood, thereby increasing the probability of endothelial penetration and subsequent oxidation. Therefore, even though polyunsaturated fats are chemically more prone to oxidation, they do not raise LDL concentrations and thus do not drive the in vivo process that actually produces oxidized LDL in the artery wall. Saturated fat, by raising LDL, is the real culprit.

LDL gets oxidized in the endothelium. LDL can penetrate your endothelium, your blood vessels, get into the intima, and there it can aggregate and it can be retained. ... Once it is retained within the endothelium, it starts to get enzymatically modified. ... And the penetration of the endothelium by the LDL is concentration driven.

Also said

“What is more likely to give you higher levels of oxidized LDL? Saturated fat or polyunsaturated fats? ... Not much is oxidized in the plasma. Most of it is oxidized in the endothelium. And that is mostly driven by concentrations, and those concentrations of LDL are raised by saturated fat.”— Directly answers the rhetorical question and ties saturated fat to oxidized LDL.

“It doesn't really get oxidized in the blood in the plasma because there's a lot of antioxidants present.”— Explains why the chemical liability of polyunsaturated fats is mitigated in circulation.

Recommendations

Products, supplements, and tools mentioned in the episode

1 item

Replace sources of saturated fat with polyunsaturated fat (seed oils) for cardiovascular and metabolic health

Practice

Based on the neutral-to-positive effects observed when substituting seed oils for saturated fat in controlled studies, and the mechanistic argument that saturated fat raises LDL concentrations which drive oxidized LDL and heart disease.

Norton concludes that for endpoints like inflammation, cardiovascular disease, insulin sensitivity, and liver fat, swapping saturated fat for seed oils yields either neutral or beneficial results, with worst-case being neutral. He emphasizes that if you are concerned about heart disease and inflammation, you should be far more worried about saturated fat intake than about seed oils. This is a direct reversal of the messaging from anti-seed-oil advocates. The recommendation is not to overconsume any oil, but to use polyunsaturated fats as a replacement when dietary fat is already present, rather than adding them on top of a high-saturated-fat diet. The underlying data from multiple studies show no increase in inflammatory markers, arachidonic acid, or oxidized LDL with high linoleic acid intake.

vs alternatives

Compared to the anti-seed-oil advice that fears linoleic acid and promotes saturated fat from sources like butter, tallow, or coconut oil, the weight of evidence presented favors polyunsaturated fats for reducing LDL cholesterol and downstream oxidation.

When it comes to inflammation, cardiovascular disease, insulin sensitivity, liver fat, when you substitute seed oils in place of saturated fat, they're either neutral or positive effects. Worst case is neutral.

Also said

“If you're worried about heart disease and inflammation, you should be way more worried about saturated fat.”— Directly prescribes a shift in concern from seed oils to saturated fat.

Find Replace

Notable quotes

Lines worth pulling out — contrarian, specific, or perfectly phrased

3 items

Seed oils not inflammatory, do not increase oxidized LDL levels. And if you're worried about heart disease and inflammation, you should be way more worried about saturated fat.

Succinctly encapsulates the entire thesis of the episode, directly challenging a widespread nutritional fear.

When you actually give high amounts of seed oils, they don't increase inflammatory markers and they don't increase arachidonic acid.

Contradicts the core mechanistic claim of the anti-seed-oil movement using experimental evidence.

What is more likely to give you higher levels of oxidized LDL? Saturated fat or polyunsaturated fats? ... That is mostly driven by concentrations, and those concentrations of LDL are raised by saturated fat.

A rhetorical pivot that reframes oxidized LDL as a function of particle number, not fat unsaturation.

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Topics covered

seed-oilsinflammationlinoleic-acidarachidonic-acidoxidized-ldlsaturated-fatpolyunsaturated-fatcardiovascular-diseaseldl-concentrationendotheliumpaul-saladino

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Educational summary of the cited expert source — not medical advice. Open the source recording linked above and consult a qualified physician before acting on any protocol.