How We Got Omega Fat Wrong – This Will Change Your Mind

"That’s a 52% reduction in all-cause mortality for those at the highest Omega-3 AND Omega-6 levels."

Whether it’s a lioness lovingly carrying her cub in her maw or a discussion about nutrition, it’s all about perspective.

Let me give you some examples to start us off. If I told you, “My diet today has been 100% carbs,” you might get a particular image in your mind. But then I’d reveal it’s 6:30 am as I write this, and I’ve only had black cold brew coffee. Or I might tell you that broccoli has more protein per calorie than a ribeye steak. But if we compared the absolute protein content of each of these foods… well… I hope you know the answer to that one.

Perspective shapes everything. Sometimes, we can flip our viewpoint easily, like with morning coffee and carbs or ribeye steaks and protein. But sometimes, the more informative lens takes effort to uncover. That’s what we’re going to do together in this letter — unpacking the story of Omega-3 and Omega-6 fats.

Omega-3, Omega-6, and the Omega-6/3 Ratio

As a brief primer: Omega-3 and Omega-6 fats are both essential nutrients — we need to consume them in our diets. Omega-3s come primarily from *fatty fish, and Omega-6s largely from *plant-based foods. (See the nuance note at the end of this section.)

The common belief is that, while both classes are essential, Omega-3s are “heart-healthy,” “brain-healthy,” and more is generally better for you. Omega-6s, on the other hand, are considered easy to over-consume in modern diets, especially through processed foods and industrial seed oils. They can also be converted in the body into pro-inflammatory compounds.

What’s more, research consistently suggests that the balance between these fats matters. A lower Omega-6/3 ratio is associated with better health outcomes — including reduced cardiovascular risk and lower all-cause mortality.

So, it's understandable why many conclude: Eat more Omega-3s; Eat less Omega-6s; Improve your 6/3 ratio — and better health will follow. Sounds reasonable, right?

Hold that thought. And remember our theme: perspective. Because the full story of these fats is a more complex than the ratio alone might suggest.

*Nuance Note (Skippable, for the purposes of this letter):

The idea that Omega-3s come from fish and Omega-6s from plants is a simplification. Each class of fatty acids contains several types. For Omega-3s, there’s short-chain ALA and long-chain EPA and DHA. ALA is mostly found in plants, while EPA and DHA are found mainly in animal-based foods, especially fatty fish. (There are exceptions — e.g., DHA from algae oil.) Focus is often placed on EPA and DHA because they appear to carry most of the health benefits. The body doesn’t efficiently convert ALA into its longer chain siblings. Also, no food contains just one type of fat — they’re all complex mixtures. Animal foods do contain Omega-6s as well, though typically in lower amounts. Furthermore, the delivery vehicle for these fats (e.g. associated polyphenolic compounds that can protect against oxidation, or the manner in while the fatty acid is physically bound to other molecules, like lysophosphatidylcholine-DHA, all impact their health effect. And that’s only the first few feet of the rabbit hole.

UK Biobank Study

In the study I want to review with you, researchers measured blood levels of Omega-6 and Omega-3 in 85,425 people and followed them for an average of 12.7 years. Over that period, 6,461 participants died of various causes. The researchers examined the association between fat levels and mortality — including the Omega-6/3 ratio.

They found that higher Omega-6/3 ratios were associated with a greater risk of death. Specifically, the highest quintile (median ratio of 14.8) exhibited a 26% increased risk of all-cause mortality relative to the lowest quintile (median ratio 5.9).

*Associations of the the Omega-­6/3 ratio with all-­cause mortality. Data were extracted from Table 2 of the paper. Media value of the Omega-6/3 ratio for each quintile is also provided, ranging from 5.9 (first quintile) to 14.8 (fifth quintile). All HR are adjusted for age, sex, race, BMI, smoking status , alcohol intake status, physical activity, and comorbidities.

So once again, the conclusion seems clear: High Omega-6/3 ratio = bad. Lower ratio = good. Therefore, eat less Omega-6, more Omega-3, and you’ll optimize the ratio. Right?

Well… not so fast. Here’s where we revisit “perspective.”

Both Omega-6 and Omega-3 Associate with Better Outcomes

The researchers ran additional analyses — this time looking at Omega-6 and Omega-3 levels individually rather than as a ratio.

And the result? Both higher Omega-6 and higher Omega-3 levels were independently associated with lower all-cause mortality. In other words, more Omega-6 in the blood = better outcomes. More Omega-3 = better outcomes.

Even though the Omega-6/3 ratio was linked to worse outcomes at higher values, the numerator of that ratio (Omega-6) was still associated with better outcomes when looked at on its own.

Surprised?

Here’s one way to think about it: Higher levels of both fats may be beneficial, but Omega-3 appears to have a stronger effect. When we analyze the ratio, it gives the impression that more Omega-6 in the body is worse; however, we are now starting to see how that story can be misleading.

If this part doesn’t fully click, I encourage you to read it again — it’s a foundational insight (and will put you in the top 0.1% of understanding the confusion around the “seed oil” debate.)

Omega 3 and Omega 6: The Effects Compound

Now I want to show you a graph that’s slightly more involved than the one above. I created this based on data from the study’s supplementary materials. So, if you want to fact check me, the original raw data are in Supplemental Table 5 of the paper.

Here’s how to read it:

• The X-axis shows Omega-3 quintiles (participants split into fifths based on their blood Omega-3 levels).

• The Z-axis shows Omega-6 quintiles (same concept).

• The Y-axis is relative risk of death from all causes, normalized to 1.0 for the group with the lowest Omega-3 and Omega-6 levels.

Bars lower than 1.0 indicate reduced risk — so, for example, a bar at 0.67 = 33% lower risk.

Now look at the trend: As you increase either Omega-3 or Omega-6 levels individually, risk of death goes down. The Omega-3 effect is stronger, but both help.

And the effects compound! The group with the highest Omega-3 and highest Omega-6 levels had the lowest mortality risk — a relative risk of just 0.48.

That’s a 52% reduction in all-cause mortality for those at the highest Omega-3 AND Omega-6 levels.

That’s not what you’d expect if Omega-6 were the villain in this story. So again, I’ll echo the word that started us off: Perspective.

Seeing the Omega-Third Dimension

Let’s pause to double click on our key takeaway thus far: When we focus on the Omega-6/3 ratio, we see a story of imbalance and risk. But when we look at Omega-6 and Omega-3 levels individually, the story shifts — and becomes more nuanced.

Both are associated with better health outcomes. This is the power of perspective. It’s easy to misjudge — just like accusing a lioness carrying her cub of infanticide instead of perceiving her tender maternal care. If we focus only on one part of the picture, we risk misunderstanding the whole. But we’re not done yet…

In the rest of this letter, we share and discuss:

• Why You Should Prioritize Omega-3. And Don’t Fear Omega-6

• Ranking of Omega-3-Rich Foods (A Printable Table)

• Nick’s “PUFA Pyramid” (A Transparent Guide)

• Where you can find More Information on Omega-3, Omega-6 and Seed Oils

• How to Get Your Own Omega-3 and Omega-6 levels