Alzheimer’s disease is personal for me.
When I found out in my early 20s that I was at high genetic risk for Alzheimer’s disease (an ApoE4/4 genotype), I was terrified.
But over time, I’ve come to see that knowledge isn’t a burden, It’s a privilege.
A predisposition is just that—a vulnerability, not a destiny. And our choices, made consistently, can shape the trajectory of our health more than our genes ever could.
Knowledge is power—and, knowledge can also be motivation.
Today, I want to share that power and motivation with you, in the form of science-backed insight.
Together, we’ll explore the paradox of omega-3s in brain health—why some work, most don’t, and what that means for you. By the end of this letter, you’ll walk away with clear, actionable strategies you won’t find anywhere else.
Roadmap
The Omega-3 Paradox: We’ll explore why large studies show that omega-3 supplements often fail to protect the brain, even though we know eating fish is beneficial for the brain.
The “Express Courier” for Your Brain: We will unpack the fascinating science of a specific delivery system that determines how efficiency and effectively omega-3s get to where they need to go.
The Action Plan: I will share exactly how to apply this science, including the best food sources and specific supplements to consider.
Let me start by presenting you with a paradox: There is a clear signal that eating more dietary omega-3s is associated with lower rates of Alzheimer’s disease and superior cognitive longevity.
However, clinical trials with omega-3 supplementation have yielded mixed and rather disappointing results.
The Big Question is: WHY?
Omega-3 Fats: A Letter with No Address
There are several possible answers. But the most metabolically interesting to me has to do with the form in which omega-3s are packaged.
Omega-3s in seafood come in diverse forms, including triglycerides and phospholipids. However, the supplements used in most clinical trials provided omega-3 PUFAs primarily in free fatty acids, ethyl esters, or triglyceride forms, not phospholipids.
The point is this: the form matters.
In particular, the phospholipid form of omega-3s has special access to the brain through a transporter called MFSD2A.
This is one explanation for why supplements fail, while fish prevail.
As an analogy, think of it like this, consuming DHA as free DHA or in triglycerides is like sending a letter with no address—it never reaches the brain.
But if you have the right form of phospholipid-bound DHA, it’s like sending a letter via express courier, straight to the right neuron.
Lyso-DHA: The Express Courier to the Brain
A study that beautifully demonstrated this point was conducted in mice, given the long-chain omega-3 DHA either as free DHA or bound to phospholipids—specifically as lysophosphatidylcholine-DHA (Lyso-DHA).
Consider Lyso-DHA the “express courier” to the brain.
The researchers found that Lyso-DHA could more than double brain DHA levels (dose: 40 mg/kg).
Importantly, this was a very different pattern than what was seen with free DHA, which did not increase brain levels but instead preferentially accumulated in fat cells and other peripheral organs.
Pause and think about this for a moment: We talk about omega-3s—including DHA—without ever discussing the biochemical packaging in which they’re delivered.
But these data clearly show that packaging matters: free DHA went to fat, whereas Lyso-DHA went to the brain.
You don’t need a PhD to read these graphs. They’re striking!
But even more striking were the downstream cognitive effects.
In this study, Lyso-DHA improved cognitive performance tremendously, whereas the free DHA did not.
You can see that below. These are results from a water maze test, where the Y-axis represents the time it took the mice to solve the maze in the “probe trial”—essentially, how long it took them to remember and navigate to the position of an escape platform.
For the control and free DHA-treated mice, it took ~25 seconds, with no difference between the two groups.
But for the Lyso-DHA-treated mice, they solved the maze in under 5 seconds!
This tremendous improvement in cognitive performance may be related to the fact that Lyso-DHA in the brain boosted levels of brain-derived neurotrophic factor (BDNF).
The point is this: Lyso-DHA outperformed free (i.e., “normal”) DHA in boosting brain DHA levels and improving cognitive performance.
Reproducible Findings
Let me also emphasize, these are reproducible findings.
In another study, researchers fed animals equal amounts of DHA in different forms, including the typical triglyceride-DHA (TAG-DHA, red) or Lyso-DHA (LPC-DHA, orange).
Clearly, Lyso-DHA dramatically increased brain DHA levels, whereas the more common forms found in typical omega-3 supplements preferentially raised adipose (fat) tissue levels.
And, again, the Lyso-DHA improved memory and cognitive performance and boosted BDNF levels more than its counterparts.
To put it simply: if you care about delivering DHA to the brain — arguably our most critical and vulnerable organ — Lyso-DHA is the form you want.
Why This Matters
Remember I said, “[S]upplements used in most clinical trials provided omega-3 PUFAs primarily in free fatty acids, ethyl esters, or triglyceride forms, not phospholipids.”
Well, now perhaps you understand the apparent paradox and why the brain health and longevity signal for omega-3 is rather weak: We are mailing a letter that, no matter how poetically composed, is without an address.
For those of us serious about cognitive longevity, understanding this nuance is non-negotiable.
The rest of this letter, for premium subscribers, dives into critical nuances, protocols, and practical strategies to optimize your long-term brain health.
Here’s what you’ll discover inside:
Why this matters for human biology—not just theory, but relevance to you
How to boost DHA levels in the brain
The core functions of DHA in the brain in cognitive performance, resilience, and repair
Specific guidance and further resources on Alzheimer’s, ApoE4, & protecting your brain
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