#420 The Weird Connection Between Omega 3 and Your Heart Health - Dr William Harris, PhD

William S. Harris (0:00)

Death from any cause, death from cardiovascular disease, death from cancer, death from all remaining causes. And we're seeing the higher the omega-3 level, the lower the risk of death. But the omega-3s are protective across a wide variety of outcomes, which all manifest at the end of the day in lower risk for dying.

Siim Land (0:18)

welcome to the Siim Land Podcast. Today, our guest is Dr. William Harris. Dr. Harris is one of the world's leading experts on the health benefits of omega-3 fatty acids. He has a PhD in human nutrition from the University of Minnesota, and he has authored over 300 publications on fatty acids, omega-3s, and fish oil. Dr. Harris, welcome to the show.

William S. Harris (0:39)

Thank you very much. Great to be here.

Siim Land (0:42)

Yeah, I'm happy to speak with you. And you've done a lot of research about omega-3s, and you're very well known in the space. I'm happy to discuss with you about all things omega-3s, because I think like fish oil and cold liver oil were one of the first supplements that I as a child knew about in terms of like, okay, these things have health benefits. And I always like to say that even like, even your grandma knows that fish oil or like omega-3s are good for you, or that they have health benefits.

So, yeah, I guess we can start like, you know, this knowledge has been around for like decades. We can start with like, okay, what's the understanding about the health benefits of omega-3s, you know, now in the early 2020s?

William S. Harris (1:30)

Yeah, well, thank you for mentioning grandmothers. Back in the day when kids used to be given cod liver oil, boy, it went back into the easily in the 1940s and before. They didn't know anything about omega-3. They knew cod liver oil was good for vitamins A and D, and that's why they gave them. They didn't realize they were also giving the benefit of omega-3s, which were discovered some 20 years, 30 years later. So anyway, there was an upside. It still tasted rotten, but you know, that's part of being a kid, I guess you got to suffer through that. So where we are today, 2024, on the health benefits of omega-3, they are, as you know, and as you've talked to your audience before, there are many stretching from cardiovascular disease, which is a large field, and endothelial, the health of the blood vessels throughout the body.

We've looked at risk for death. We do a lot of studies nowadays looking at blood levels of omega-3 and how they relate to future disease outcomes. And so we've been looking at the big one, dead, death from any cause, death from cardiovascular disease, death from cancer, death from all remaining causes. And we're seeing the higher the omega-3 level, the lower the risk of death. Of course, everybody dies eventually, so you gotta say risk for death in a window of time, certain between this time and that time, between this age and that age. But the omega-3s are protective across a wide variety of outcomes, which all manifest at the end of the day in lower risk for dying. Cognitive benefits, we're seeing, again, people with the higher omega-3 levels are lower risk for developing dementia, which is a big deal these days, and just a variety of other diseases. So high omega-3 is really good for about every system you can think of.

Siim Land (3:48)

Right. And why is that so? So as I understand, then some of these omega-3s, they're not necessarily considered essential, or they're more conditionally essential.

But what are some of the reasons why you see such a consistent finding, that people who have higher blood omega-3 levels, they have lower risk of heart disease and mortality? So what are the mechanisms that give those effects?

William S. Harris (4:20)

Right. And that's always the next question down. I suppose we should define omega-3. When I'm talking about omega-3, I mean the long-chain, marine-derived, EPA, DHA.

Those omega-3s, not so much the plant ALA, which probably is the essential omega-3 fatty acid. EPA and DHA are, as you suggested, conditionally essential, meaning they're nutrients that you don't have to have in your diet to live and reproduce, but they are nutrients that, when in the diet at higher levels, give you better health outcomes. It's a little bit different than the classic meaning of essentiality and nutrition, where if you haven't got it, you're dead. And that's not the case. If you haven't got it in your diet, you're dead. Because we can make EPA and DHA to some extent, and probably to a sufficient extent, to allow you to live and reproduce. And the best evidence of that is simply looking at cultures that are vegetarian or vegan, where they consume no EPA and DHA pre-formed, but they consume ALA, and they're still with us.