51. The Seed Oil Studies Are Measuring the Wrong Thing

A new seed oil study may look reassuring at first glance — but what did it actually measure?

In this episode, Zane Griggs breaks down a 2025 review of clinical studies on seed oils and explains why short-term improvements in blood markers do not necessarily tell us what is happening inside the mitochondria.

You'll learn why the real concern is not only what shows up in a blood draw, but what happens when polyunsaturated fats become incorporated into mitochondrial membranes over time.

Zane walks through:

• what the seed oil review actually found
• why flaxseed and sesame oil are not the same as soybean or corn oil
• the difference between blood markers and mitochondrial damage
• cardiolipin, ATP production, and oxidative stress
• why 4-HNE and other aldehydes matter
• how cooking oils change when heated
• why stored linoleic acid can remain in the body for years
• why a short-term study may miss a long-term mitochondrial problem
• how soybean oil consumption has changed over the last century
• why stable fats may matter more than most people realize

Studies:

• Laurindo et al. Frontiers in Nutrition. 2025;12:1502815
• Hulbert AJ et al. Physiological Reviews. 87:1175–1213, 2007
• Seebacher F, Brand MD, Else PL, Guderley H, Hulbert AJ, Moyes CD. Physiological and Biochemical Zoology. 83(5):721–732, 2010
• UC Riverside / Journal of Lipid Research, November 2025
• SNI Global soybean oil consumption data

The point is not to ignore studies that show short-term improvements. The point is to understand their limitations and ask whether they are measuring the outcome that actually matters.

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00:00 The seed oil study everyone is going to cite
01:00 What the 2025 review actually measured
02:00 Why flaxseed and sesame oil are different
03:30 The short-term benefits are real — but limited
04:00 The problem with relying on blood markers
05:00 What happens inside the mitochondria
06:00 Cardiolipin and ATP production explained
07:00 The damage the studies did not measure
08:00 Why higher antioxidant activity can be misleading
09:00 The researchers admitted a major limitation
10:00 They did not verify the oil composition
11:00 Why processing, heat, and storage matter
12:00 Fast-food fryer oil is not the same intervention
13:00 How stored linoleic acid remains in the body
15:00 Why the control groups were not truly low-PUFA
16:00 The washout problem no short-term study solves
17:00 Comparing two versions of excess exposure
18:00 How much soybean oil Americans consume
19:00 Physiological need vs modern consumption
21:00 Why the baseline recommendation may already be too high
22:00 The UC Riverside soybean oil research
23:00 Oxylipins, liver health, and mitochondrial function
25:00 Why standard blood tests may miss the damage
26:00 The peroxidation index explained
27:00 Omega-3 vs omega-6 vs monounsaturated fats
28:00 Why more fish oil may not solve the problem
29:00 Saturated fat and mitochondrial membrane stability
31:00 What membrane fluidity actually requires
32:00 Why longer-lived species matter
33:00 What the pro-seed-oil literature can and cannot prove
35:00 Short-term blood improvements vs long-term membrane loading
36:00 What fats Zane recommends using instead
38:00 Why ingredient labels matter
39:00 Final takeaway: read the studies carefully