Omega 1-2-3
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It was a little bit of a grueling thing.
It's funny, I never went out on a jet ski as a younger person, and I was, I think, 47 when I started on this book.
So it turns out riding a jet ski is not a lot of fun if you're 47.
The jet jet ski-mounted hero of today's episode is 47-year-old Paul Greenberg.
Well, he's not 47 anymore.
That was when he started the book, so he's a few years past that now.
Like us all, he's getting older.
And that actually is what led him to the topic of his book.
I did start this book, you know, in the throes of kind of a panic about middle age.
And when you Google all the things that are going wrong with you in middle age, your joints hurt, blood pressure's going up, losing your memory, and you Google solutions for this, you you know, what comes up again and again are omega-3 supplements.
So it struck me as a way, a lens for looking at the omega-3 was to look at it through the lens of the sort of panic that you get in middle-age around all these things.
This episode is not about the panic.
It's about the omega-3s.
In fact, Paul's book is called The Omega Principle.
Omega-3s have come up in our reporting this year.
You might remember we talked about how important these fats are in our Alzheimer's episode.
But what are omega-3s?
And why is everyone from Dr.
Oz to the American Heart Association telling us to eat more of them?
Is there any science behind the idea that omega-3s are miracle molecules?
You've probably heard that there are omega-3s in oily fish like salmon, but what about the pills you can buy at the drugstore?
Where does the omega-3s in those come from?
And what is this omega-3 boom doing to our oceans, not just our bodies?
All that, plus, some adorable and mischievous sea lions.
So, 47-year-old Paul is on a jet ski with his guy, Jet Ski Brian.
I I told him I didn't really want to go fishing.
I wanted to actually watch this company called Omega Protein fish for Menhaden.
Paul was on his jet ski in the Chesapeake Bay, watching this big blue ship scoop up these tiny silvery fish called Menhaden.
The company that owns the ship, Omega Protein, it's actually the largest processor of Menhaden in the U.S.
Paul watched the mothership lower little aluminum baby ships into the water.
The boat circled the school of thousands of Menhaden, and they they scooped them together with a net.
The ocean went frothy as the little fish thrashed around in the net, and Paul said suddenly the air smelled like watermelon.
Apparently, that's what menhaden smell like, although I wouldn't know because I've never eaten one.
Me neither, and probably none of you listeners have either, because none of these oily menhaden get eaten.
They're being converted into things like fish meal and fish oil, fish meal to feed animals, and fish oil for omega-3 supplements.
So, what are these magical omega-3 things?
Omega-3 fatty acids are polyunsaturated fatty acids.
You know, you can go wheels within wheels to get more and more deeply exactly what that means.
But basically what it means is that they have a double bond in the tail end of their structure between two carbon atoms.
And that makes them much more sort of dynamic and flexible.
And that flexibility of these omega-3 fatty acids is awesome for fish that swim fast in cold waters.
But these types of fats first evolved not to help with swimming, but to turn sunlight into energy.
They played a key role in photosynthesis in the very earliest and simplest microscopic creatures that swam in the oceans.
These little phytoplankton guys, they're like tiny, super basic algae.
They only did one thing, which was photosynthesize.
And they were making omega-3s to grease the wheels of their sunlight harvesting machinery.
And they got really good at it.
They harvested so much sunlight and breathed in so much carbon dioxide that they completely changed Earth's climate.
But not the climate change we are all obsessed with, but climate change going in the other direction.
So back in the days of the early Earth, we had an atmosphere that was very soaked in carbon dioxide.
As you might have heard, carbon dioxide in the atmosphere keeps things pretty hot.
So then when those phytoplankton used a lot of carbon dioxide, the atmosphere got colder, pretty dramatically colder.
Which fortunately, the little phytoplankton could adapt to thanks to our heroes, the omega-3s.
It turns out that having omega-3 fatty acids in your membranes makes your membranes more pliable and more dynamic at colder temperatures.
One important thing about omega-3s is that they come in different flavors.
There's the one used in photosynthesis called ALA, and it's still around in leafy green plants today.
And then there's one called DHA.
The early sea creatures turned their ALA into DHA to make them cold water powerhouses.
That's basically what it was used for.
But, you know, as evolution goes, of course, whatever things were originally designed for gets repurposed and reconfigured for other purposes further down the line.
The first phytoplankton were photosynthetic, but if you have a system for gathering light, it's just a few short evolutionary steps to having a system for sensing light, aka the eye.
And these plankton with eyes became hunters.
They started eating the eyeless photosynthetic plankton to get their energy.
And then at some point in evolutionary history, those hunter plankton didn't bother making omega-3 fatty acids themselves anymore.
They just ate them.
These omega-3s, specifically the DHA variety, they still play an essential role in the parts of the eye that pick up light for all animals with eyes, including us.
We couldn't see without omega-3s.
What I found throughout looking at omega-3s was it's kind of the forest gump molecule.
First of all, omega-3s are everywhere in the plant world because they're critical for photosynthesis.
Omega-3s are literally the most abundant fat on earth.
And then, as we just said, they're critical in all animals' eyes for the same light-sensing reason.
Basically, they're so bendy and flexible that they're super useful anywhere you want to be dynamic and mobile.
Anything that has to move fast or transmit signals fast.
Moving fast, so remember those tiny watermelon-scented menhaden?
They have to swim super fast in cold water, and so they're super oily and packed with omega-3s.
And another tiny creature that has to swim really fast, sperm, also full of oily omega-3s.
Other places you might find this forest gump molecule are the heart, depending on your blood pressure, that's moving pretty fast.
Also, hummingbirds.
Their wings have to beat 52 times per second, and so those muscles are crammed with omega-3s.
Another weird place you can find omega-3s in the hooves of the caribou that roam the frozen tundra.
The fact that omega-3s stay flexible in the cold helps keep the caribou's blood circulating, even when their hooves are marching through the super cold permafrost of the Arctic.
But the tissue with the largest amount of omega-3s is your brain.
Your brain isn't moving, but all the cells in it are sending signals really fast, so they need to be bendy and flexible too.
In fact, a few decades ago, a scientist named Michael Crawford got interested in the relationship between omega-3s and our brains.
Yeah, so Michael Crawford, he was based in Africa, and he did some initial comparative analysis of different brains.
And I think he looked at 40 different mammalian brains, and what he found was that the size of your brain was directly dependent on the amount of DHA omega-3 fatty acid that was available.
So that, you know, sort of leading to this conclusion later on that omega-3s, DHA, omega-3 fatty acids were an essential part of the human brain.
As I said before, those earliest hunters with the earliest eyes, they didn't bother making omega-3s, even though they needed them, because they could just eat them.
And we're the same way.
We eat all the omega-3s we need, either from green plants or really mostly from oily fish that eat those plankton to power their cold water tolerant bendy muscles.
There are so many freaking phytoplankton making omega-3s.
I mean, literally, there's one species of phytoplankton alone that is the most abundant species on Earth.
So although almost all animals need omega-3s, pretty much none of them actually bother making them.
Omega-3s are the fats everyone is obsessed with, and you can see why we need them to think and to see, but they aren't the only omega-fats out there.
Any plant that can photosynthesize can make omegas, and not just omega-3s.
There are omega-6s, there are omega-9s, omega-12s, there's all sorts of omegas.
You've probably heard of omega-6s.
They're not as famous as omega-3s.
They're like the less well-known, less desirable sibling.
Organisms that use omega-6s as their primary fatty acid tend to be more rigid because the omega-6 itself is a much more rigid structure.
So when we look at things like corn and soy, particularly corn oil and soy oil, they tend to have a nutritional profile that leans towards omega-6.
And in fact, many things on land are going to tend towards omega-6 because, well, they need to stand upright.
Omega-6s are also actually a critical part of our diets.
We die without them.
They're in seeds and seed oils, corn oil, sunflower, and safflower, and soy oil, sunflower seeds, pumpkin seeds.
And even though they're essential, they get a bad rap these days, which we will come back to.
Yes, we are going to come back to the relationship between these fatty acids and our health.
But overall, it's clear that the fatty acids are found in so many parts of our bodies and that they're essential to our existence.
But how did we figure that out?
The answer involves rats with dandruff, spam, and a Baptist scientist.
The story starts back in the 1800s.
That's when scientists first really started to figure out what it was in food that was good for us.
So you had the 19th century, which was all about the discovery of vitamins and minerals, right?
And we kind of went through that whole thing.
We talked about that whole thing in our vitamin episode, this complete shift in our our understanding of what food was doing for us and our health.
And into the 20th century, medical research was always looking for new angles, and people started to wonder, did fat have any kind of nutritional quality to it?
Back then, everyone knew fat was a great source of energy in the form of calories, but no one realized they were essential.
Like, you would die without fat.
Until George and Mildred Burr came along in the 1920s.
These two scientists, the Burrs, a husband and wife team, that did these deprivation experiments with rats where they deprived them of fat and then saw that when they didn't have fat, they actually wasted away and had all these, you know, other physiological problems.
The rats looked pretty bad without any fat in their diet.
They had dandruff and scaly skin, their tails swelled and got ridges, they had no fur around their faces, and then they died.
But if the burrs gave them just three drops of lard before it was too late, they recovered.
Pigs eat everything.
Some of those things have omegas in them, and so lard has some omega-3s and sixes in it.
Not that anyone knew an omega from Adam at the time.
Omegas hadn't yet been discovered.
No one knew which of the chemicals in fats was saving the rats' lives.
So it was established that fats were important, but then what kinds of fats.
And then a lot of sort of deepening research happened in the 50s, 60s, and 70s.
Ralph Holman is the guy who discovered the omegas.
George Burr was his thesis advisor.
George and Mildred Burr did their rat fat deprivation study, and then they quit and moved to Hawaii to study pineapples.
And Ralph Holman picked up the fat torch.
Used to work for the Hormel company that was, you know, worked on spam and so forth.
All the different fatty foods and oils you might find in your kitchen have a combination of different fatty acids in them, like lard, which is mostly an animal fat you've heard of called saturated fat, but it also has these omega-unsaturated fats.
And some of those different types of fatty acids go rancid more quickly than others.
Hormel wanted Ralph Holman to figure out which fats went bad so the company's spam wouldn't go bad.
So Ralph did experiments to figure out what all these different fatty acids are, which meant he was the one who discovered omegas and got to name them.
He was a Baptist growing up and he knew his Bible really well and he came up with the nomenclature and decided to call it omega-3
because there's a line I think in Revelations, I am the alpha and the omega, the first and the last, etc., etc.
In the Greek alphabet, alpha is the first letter and omega is the last.
It's at the end.
And that's also where the distinguishing feature of these special fats is, the chemical structure that makes them so bendy and pliable.
So if you count three carbon atoms in from the end, that's where you'll find your first double bond.
So that's why it's called the omega-3.
And if the first double bond is six carbon atoms in, well, you're looking at an omega-6, and so on.
Omega-3s just have more double bonds all along their length.
These double bonds are what make them so flexible, but these bonds also react really easily with oxygen, and that makes them turn rancid super quickly.
Ralph's discovery was useful to Hormel.
Eventually, scientists figured out how to get rid of those omega-3s in processed foods to make them more shelf-stable.
So, at this point in history, thanks to George, Mildred, and Ralph, and Spam, all thanks to Spam.
So, at this point, we've identified omega-3s.
We know that rats will develop dandruff and die without fat, but we don't know what those fats are doing that is so essential.
Meanwhile, scientists have started connecting animal fat and cholesterol to heart disease.
And so there were these two doctors named Bang and Dyerberg who went to Greenland in the early 1970s.
Olaf Bang and Jern Dyerberg went to Greenland because the Inuit there seemed like a paradox.
They ate a lot of meat, mostly from seals, and a lot of fat.
At the time, meat and saturated animal fat were thought to be the main cause of heart disease, but the Inuit had really low levels of heart disease.
So Bang and Dyerberg tested their blood.
And they were the ones who discovered that Inuit populations there had very, very high levels of omega-3 fatty acids in their blood.
They also had a diet that consisted primarily of marine mammals and fish.
While Bang and Dyerberg were doing their Greenland thing, Michael Crawford was doing his brain measuring thing, and suddenly, omega-3s were the hot new molecule on the blog.
It all kind of sort of smushed together.
And I think the very first dietary supplements that we started to see, omega-3 dietary supplements, were really kind of like early 80s.
These might have been the first supplements with the words omega-3 on the label, but they certainly weren't the first time we used fish oil as medicine.
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So Garum might just be the world's first omega-3 dietary supplement.
It was an ancient fish sauce that seems to have come possibly from the Phoenicians, although we don't know.
I wasn't there.
Theory is this fish sauce made its way from the Phoenicians through the Greeks and eventually to the Romans.
What we do know for sure is that the Romans absolutely loved it.
And in fact, if you go to Pompeii, if you were to try and reconstruct what Roman civilization was built around based upon what you found in Pompeii, you would conclude that it was primarily a fish sauce manufacturing country or empire because there were so many vessels of this fish sauce called garum found everywhere.
To make garum, ancient Romans took whole anchovies or mackerel, guts, heads, and all.
They mixed the fish with a lot of salt, and then they let the whole mess rot in the sun for months.
They'd stir it occasionally, some people would add some wine, and at the end, they'd funnel off the resulting liquid.
Romans used it as a condiment.
In ancient recipes, it's more common than salt in the recipes.
So it was very salty, so it provided that aspect to it.
But it had a certain kind of stinky, umami-ish thing that it gave to food.
Sounds delicious.
But Garum was more than just fish sauce.
It was a supplement.
Romans poured it down the noses of sick animals.
They took it as a laxative, but also to cure chronic diarrhea.
They believed it could restore a lost appetite and treat everything from tuberculosis to migraine headaches.
People used it as a curative as well for sciatica.
Some people thought it could cure an upset stomach.
People associated it with amorous qualities as well.
It was a big deal.
Romans brought their garum with them everywhere.
Turns out they might have been onto something.
Recently, some Spanish food scientists reconstructed how you would have made garum because it was not exactly like the way we would make a supplement today.
They would just take a bunch of guts and heads and so forth and let them basically rot and ferment and the liquid that came off of them was garum.
Anyway, they did that, and then they sort of tested it for its nutritional qualities, and had a number of very useful nutrients, including being very high in omega-3 fatty acids.
You might never have heard of garum, that's kind of ancient history, but you might have heard of something that was used for a lot of the same health benefits, and that's cod liver oil.
Or maybe not, because if you remember taking cod liver oil, you are pretty much an archaeological specimen yourself.
Cod liver oil is sort of an interesting case because those who are a little bit older older might remember a day when they didn't know exactly what an omega-3 was, but they did take cod liver oil.
Cod liver oil is actually very high in omega-3s.
And the reason, so cod themselves, if you eat a fillet of cod, it's actually not particularly omega-3 rich or particularly oily.
Cod tend to store their oil in their liver.
And one of the reasons they do that is because it allows them to shuttle the omega-3s over to their gonads when it's time for reproduction.
And just like human testicles, cod balls require plenty of omega-3s to do their sexy things.
We humans have been taking omega-3 supplements in fish oil for thousands of years, actually.
If you consider the history of people swallowing some garum or cod liver oil to help with various ailments, they didn't know those were omega-3s.
The people buying supplements today, though, they certainly do.
Ralph Holman went to the store, this guy who had named them the omega-3 fatty acids, went to a store and saw a jar of
fish oil, and it said, omega-3s are here, and he bought it and he was so excited.
Today, Paul says the omega-3 supplements are a $15 billion industry, an industry that's still growing at 7% each year.
Omega-3s are also one of the world's most profitable supplements.
After all, they're supposed to help with diseases of aging, heart disease, dementia, cancer, even.
And the West is clogged up with all these boomers right now who don't want to go quietly into the night.
But as big a market as those aging boomers are for the supplement industry, and it's a huge, huge market, it's not actually the biggest market for these tiny fish.
Today, oily fish full of omega-3s are a super important ingredient in animal feed.
And this is really the key, the killer app, so to speak, for little fish.
First they started feeding all these little fish to chickens.
Then they fed them to pigs.
What happens is, in industrial hog production, piglets are not allowed to nurse for very long, so they don't get enough omega-3 fatty acids from their mother's milk.
So the farmers have to add omega-3s to the pig infant formula.
And this means that fish oil and fish powder have gone industrial.
Chicken feed, pig feed, and actually it's a major ingredient in cat food too.
And so a lot of the fish caught in the world are not eaten as fish.
Yeah, a lot.
It's something like 20 to 25 million metric tons a year, which is, you know, around close to a quarter.
of all the fish that we catch is reduced.
This completely invisible thing.
And, you know, if you were to weigh that, you know, 25 million metric tons, what is that?
That's actually the equivalent of the human weight of the United States taken out of the sea every year.
It is impossible to picture that, but obviously it's a lot.
Today, the biggest market for all those ground-up tiny fish is other fish.
farmed fish.
Because there are a lot of fish out there that just simply need omega-3s.
They just will die if they don't get omega-3s, salmon being one of them.
So probably the global salmon industry is probably the biggest market right now for all these little fish.
It's not just that some animals can't live without omega-3s, salmon for instance, and baby pigs, it's also that other farmed fish, they grow faster when their diets are supplemented with fish meal.
The little fish that are feeding all these bigger fish, for the most part, we've never heard of them.
Like the Menhayden that Paul jet skied out to sea in the Chesapeake, or like the Peruvian Anchibeta, which is the largest fishery in the world.
Sometimes it's been as much as more than 10% of the world catch, so a huge amount.
And again, 99% of it goes into animal feed, dietary supplements.
Paul traveled to Peru to see what a fish catch at this scale looks like.
He sailed with a fisherman out into the turbulent Pacific at 2 a.m.
And I thought we were immediately going to go to the fishing grounds, but instead we stopped about an hour or two in and just waited.
And I said, well, why are we waiting?
He's like, well, we have to wait for the other boats.
I'm like, you know, that just goes totally contrary to everything a fisherman always thinks.
You know, I want to be the first one out to the grounds.
I was like, why?
And so, well, you'll see.
So they wait.
And then suddenly there are dozens and dozens of boats all around, all sailing together towards the same point.
And I realized why we were doing this.
And the reason we were doing this is because there were so many sea lions that immediately got on the fishing nets that if you didn't have a number of boats, they would all congregate around one boat and basically eat your net to shreds.
And what was really interesting about it was that, you know, you always see these sort of greenpeace moments of like, oh, the poor sea lion who got caught accidentally, he was just minding his own business and he got scooped up by the net.
But what's kind of crazy about the Peruvian situation, the sea lions totally knew the game.
These sea lions were just lounging around, waiting for the humans to gather all the anchoveta together into a nice oily anchiveta bowl.
And then they would jump in the net.
And they would just, you know, sit there and they would just eat and eat and eat and eat.
And people would be shouting at them.
They'd be like, they'd stick up their noses, like, oh no, I don't want it.
It's too delicious here.
I don't want to leave.
And eventually they would kind of harass them enough so that they would leap over the net and get out.
So it looks to Paul like a pretty healthy ecosystem.
There are clearly a lot of fish out there and the fishermen are all pulling in quite a hefty haul.
In both Peru and in the Chesapeake there seem to be shedloads of tiny fish even though these companies scoop out so much.
Everybody will say that their industry is totally sustainable, that they've, you know, they used to be overfished, but now they've really worked it out and da da da.
And granted, a lot of these countries and regions and companies have made adjustments.
But I always go back to the fact of
what if 25 million metric tons of fish were still in the sea?
What would the ocean look like if we had 25 million extra tons of prey, of food for whales, for birds, for the fish that we like to eat?
And nobody could ever give me a clear answer on that.
Paul's point is these little oily fish, they would normally be eaten by other sea creatures or by seabirds, or they'd die and their nutrients would cycle around in the marine ecosystem.
But now that food source is gone.
And frankly, anytime we humans think there's an endless supply of something, well, there isn't.
Hundreds of years ago, sailors said there was so much cod in the Atlantic they could practically walk across it.
Then we fished nearly all of it.
We talked about this in our counting fish episode.
There are plenty of fishermen today who will still say there's loads of cod in the ocean, even though there's nowhere near as much as there used to be.
It's called a shifting baseline.
And shifting baseline basically says that each successive generation has a diminished view of what it perceives as abundant in nature.
You know, like the example of codfish, if I go out nowadays out of Long Island and I catch five codfish, I'll think that I would have had a fantastic day.
My father, if he goes out, if he catches five codfish, will think it's a miserable day.
And my grandfather, if he'd gone out, would think that, like, what the heck has gone wrong in the universe that you could only catch five codfish.
In other words, we don't really know the environmental impact of our hunger for omega-3s, but it's a safe bet that there is one and it isn't great.
But doctors and scientists are telling us to eat seafood, salmon in particular, and a lot of them are also suggesting omega-3 fish oil pills.
And both of those things are exactly what the Peruvian Enchavettas are getting turned into, so maybe it's worth it.
Only if omega-3s are doing all the miraculous things people claim they're doing, which it turns out, scientists have something to say about.
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The interest in omega-3s has waxed and waned over the decades.
This is Joanne Manson.
She's an epidemiologist at Harvard Medical School.
Interestingly, about 30, 40 years ago, there was tremendous interest in omega-3s in having a role reducing cardiovascular disease.
This is the time that people were concerned about animal fats and heart health, and Bang and Dyerberg saw that the Inuit were doing well with their omega-3 rich diet of seals and fish, so maybe omega-3 pills would help the rest of us.
And some of the randomized trials of omega-3s that were done in the 1980s, 1990s looked promising, but then more recent trials were actually disappointing.
There was a big study last year that looked at other studies.
It's called a meta-analysis, and it showed that there was actually no heart benefit from taking omega-3 fatty acid supplements.
And that led to a lot of discouragement about omega-3s.
But Joanne says the problem was there were problems with a lot of these earlier studies.
So the randomized trials of omega-3s have included some trials with lower doses that may not be adequate dosing.
Some trials that were short duration, even less than a year or only one to two years.
It's been a mixed bag.
Those earlier studies were also done on patients who already had heart disease or had suffered from a stroke or they had diabetes.
They basically already had health issues, which meant they weren't necessarily a great test of whether omega-3 supplements would help the general public.
So Joanne set up a trial of her own.
Well, very surprisingly, the vitamin D and omega-3 trial, VITAL,
was the first large-scale randomized clinical trial of omega-3s in a true usual risk population.
Joanne's trial was called Vital, and it was a fully randomized double-blinded trial.
That meant some of the participants took a supplement and some took a placebo, and none of the doctors knew which was which.
There were more than 25,000 participants, all over 50 years old.
They were just all comers.
Some of them did have hypertension or diabetes, as you would have in the usual population, but they were generally healthy.
The folks in the trial who were getting the fish oil supplement got a gram of omega-3s a day.
The others took their placebo, and then Joanne sat back and waited for more than five years to see what happened to everyone.
Joanne told us that if you look at how many people in the trial ended up having a heart attack or a stroke, well, the omega-3s didn't make a difference.
But that changed if you took strokes out of the equation.
We saw a reduction in fatal heart attack, about a 50% reduction there.
So we did see significant reductions in coronary heart disease-related events.
We saw no reduction in stroke.
Okay, so no reduction in strokes, but the reduction in fatal heart attacks is intriguing.
Where it gets really intriguing is in the differences between different participants.
People who ate less than one and a half servings of fish a week, so they weren't getting a lot of omega-3s in their normal diet, those people, if they got the omega-3 supplement, a statistically significant percentage of them had a reduction in heart disease overall, even including stroke.
In comparison, people who did eat fish did not see a reduction in heart disease from taking the supplement.
But here's an important thing to know.
The percentage difference might look dramatic, but the numbers are really, really small.
For instance, of the more than 13,000 people who didn't eat a lot of fish, the difference in who ended up with heart disease and who didn't was only about 40 people.
Obviously, if you're one of those 40 people who didn't get heart disease, that's great.
But 40 people out of 13,000 is not nearly the huge impact it might sound like if you just hear the percentage reduction.
But it is statistically significant evidence for the benefit of omega-3s.
And there was another subgroup subgroup that seemed to benefit more than others from the supplement.
We had very dramatic reductions in the risk of heart attack among the African Americans with the omega-3s.
They actually had a 77% reduction in the risk of having a first heart attack.
Now, this could be a chance finding.
This needs to be replicated because if African American Americans are benefiting this much from omega-3 supplementation, it's really important to know that and it could play a role in reducing health disparities.
Once again, the actual numbers are super, super small.
So the results are promising, but as Joanne says, it could be chance.
Plus, we also want to point out that even if there is a benefit from the supplements for African Americans, it might have nothing at all to do with skin color.
In general, African Americans have lower incomes than white Americans, they have poorer access to health care, they tend to live in more polluted areas, and of course, not unrelated to all of these other factors, they're subject to discrimination and racism.
So our findings in African Americans could be due to a number of factors.
One possible explanation is increased stress and even increased exposure to air pollution and some environmental risk factors where the omega-3s have been implicated in having benefits.
Right now, the only results Joanne has from her vital trial are to do with heart health.
But taking omega-3s is supposed to have lots of other wonderful benefits, and the trial is looking at them too.
We're looking at cognitive function, mood depression, risk of type 2 diabetes, autoimmune conditions, and a number of other health outcomes.
We're still in the process of doing the data analyses, but stay tuned.
We will have results from many of these other studies within the next three to six months.
There's plenty more research ahead, both for Joanne and for other scientists who are looking at omega-3s in health.
These findings have to be confirmed by other scientists and there are a lot of questions.
How much omega-3s do we need?
Is more better?
But Joanne's study, which is just one study but is a really solid study, makes it seem as though omega-3 supplements are beneficial for some folks.
Assuming other scientists replicate these findings, does that mean people who would benefit from more omega-3 should get those omega-3s in pill form?
In Joanne's study, she had to deliver those omega-3s in capsules, otherwise it'd be pretty obvious who was getting the omega-3 and who had a placebo.
Some people would be eating a lot of mackerel and salmon and sardines, and some, well, they wouldn't.
But outside of the constraints of the scientific study, is consuming your omega-3s as a pill really the way to go?
So I'm glad you asked this question because I think the primary recommendation is to try to increase consumption of fish and not to jump to popping a pill.
Joanne says it's not clear whether there's really a a difference between the two, but she says that one of the benefits of eating your omega-3s in fish and not in a pill is that eating fish might be taking the place of eating something that's not quite as good for you.
So if you're having fish more frequently, you may end up having
red meat, saturated fat, processed foods less frequently, and you're replacing them with a food that's more healthful.
The other issue is that the human body has evolved to incorporate nutrients based on food.
And a lipid taken out of context of other lipids and just sort of just a shot of lipid right there in the morning when people are most likely to probably take their supplement seems to me maybe out of sync with what the body is able to deal with.
What's more, as regular gastropod listeners know, all supplements are not created equal.
Because there's no real federal oversight of the supplement business, some are pure omega-3 goodness and some are not.
The companies that are making supplements are making them from fish that weren't necessarily refrigerated upon capture.
Omega-3s are very dynamic compounds and they will oxidize very quickly.
And if they oxidize, then they're not really going to provide the health benefit that we're looking for.
The oils turn rancid, and when they're rancid, they're just not good for you anymore.
So it's important to look on the label for some of the signs of quality control, the seals of U.S.
Pharmacopoeia, USP, NSF, various ways that you can tell that there's some external audit going on for quality control.
Okay, but if you do find a good quality supplement, should you be taking it?
Should we all be popping omega-3s just as backup?
So our advice at this point would be not for the entire population to start taking an omega-3 fish oil supplement because we really are not seeing overall widespread benefits.
So, fish is best, but do I have to eat those watermelon-smelling Menhaden or what?
Well, not necessarily Menhayden, but yeah, different fish have different amounts of omega-3s.
As we said earlier, fish that swim really quickly in cold water have a lot of omega-3s.
You've heard of these fatty fish, such as herring, and anchovies and sardines and mackerel and salmon and sablefish, otherwise known as Pacific black cod, not the cod most people eat from the Atlantic.
The problem with normal cod and other white fish, haddock, tilapia, flounder, grouper, is that they just don't get enough exercise.
Cod don't swim for miles and miles and miles like mackerel do.
It'll have a quick lunge, but then most of the time it's kind of a lazy kind of fish, so it's not so essential to have these hard swimming oils in their bodies.
Yeah, if you're only eating cod and haddock, you're probably not getting enough omega-3s in your diet.
But this question of enough, this is where it gets complicated.
You know, if you're just talking to your family physician, a lot of physicians will say something like, you know, 500 milligrams a day, and you can kind of hit that amount if you have, I think it was like something like four anchovies a day, so like, you know, eight little fillets of anchovies, which is really not a lot.
But if your family physician does say this, well, it's not actually based on settled science.
We don't know how much we need of these omega-3s.
And there's another thing that makes this question even more complicated.
So here's the thing.
We told you we outsource production of omegas.
We just eat them.
And we also told you that the omega-3s used in photosynthesis, the ALAs, that they're the most abundant fat in the world.
And then we told you that our brains and our hearts need the other kind of omega-3s, the marine kind.
There's some good news here.
We can actually make that marine kind in our bodies from ALA from plants.
We can convert the plant omega-3 from flax seeds and chia seeds and leafy greens.
We can convert it into the marine omega-3 that our brains and our hearts need.
But can we make enough?
No one is sure.
And part of the reason no one is sure is because it's possible that the specific amount matters less than the ratio.
Yes, the ratio.
Specifically, the ratio of omega-6 to omega-3.
Remember, omega-6s are in corn and soy, basically in seed oils.
Omega-6s are critical, but some scientists think we shouldn't have too much of them.
Omega-6s interfere with the body's ability to elongate short-chain omega-3 fatty acids that we're getting from leafy greens and so forth.
And they also seem to lead to the production of inflammatory compounds.
And here's why.
Your body uses whichever omega happens to be handy in order to build all the things it needs to be bendy and flexible, like cell membranes.
Omega-3s are the bendiest and most supple of all, but if omega-6s are what's most available, that's what your body will use.
Scientists think that if your cell membranes are made of omega-6s rather than 3s, they're not as flexible, and the communication between cells doesn't work as well.
And the movement of other chemicals around your body, it's less fluid and more explosive because the cell membranes are a little stiffer.
And some scientists think that more explosive movement is more stressful for your body and can cause inflammation, which is bad.
Right.
And one final point here.
Food technologists have gotten rid of as much omega-3 as possible in processed food because it turns rancid quickly, as we told you.
Omega-6 doesn't go bad quite as fast, and corn and soy are so cheap, so our processed food world is full of omega-6s, far, far more than we would have eaten in the past.
So are our industrially produced animal products, because cows and pigs and chickens are fed corn and soy rather than grass and bugs and stuff.
Terrestrial meats that are fed a feedlot diet will have an omega-6 ratio far in excess of what we think probably Neolithic humans might have had in their own blood.
This is all a hypothesis.
Nobody has proven this ratio question.
In fact, when we asked Joanne about it, she didn't even want to touch it.
The basic mechanisms make sense biologically.
The idea that the ratio of omega-6 to omega-3s in our diet has changed over time, and so has the incidence of all kinds of heart disease and other industrial world health problems, that's based on observational evidence.
But overall, it's still an argument, not a fact.
Joanne agrees.
There's still huge gaps in our understanding when it comes to omegas and health.
But at the end of the day, whether or not the ratio matters, it's not a bad idea to add more oily fish to your diet.
Fish like mackerel, sardines, herring, salmon.
Farmed salmon is actually often a little higher in omega-3s than its wild counterpart, but it's being fed anchiveta.
And Paul says that's not a good use of anchiveta.
You know, the people who argue for the Peruvian anchive industry doing what it's doing say, nothing wrong with it.
We're still making human food.
We're just making these pellets that we're sending to Norway so they can feed salmon.
We're just transforming it.
I don't know if I buy that argument.
I think that, you know, a lot is lost in the process and we could probably do a lot better.
What's lost is that pound for pound you're getting less food at the end by feeding the small fish to the big fish than if you just ate the small fish.
So it's a waste.
Not to mention the energy you use to reduce the small fish into pellets and ship them around the world.
So it's not really a great idea to feed the anchiveta to salmon instead of just eating those anchiveta directly, which Paul says taste exactly like anchovies.
Or just leaving more in the oceans for all the other sea creatures.
But Paul says maybe there's a better way to feed salmon and to make supplement oil.
A way that is in fact how omega-3s are created in the first place, by tiny microscopic phytoplankton, basically algae.
I mean, why not cut out the middlemen?
Why kill
hundreds of millions of billions of fish every year to reduce into the supplement when you could grow them using algae, which would actually sequester carbon and do all these other kinds of things things in the process.
This is actually something people are working on.
They're growing algae and harvesting omega-3s.
You can find algae-based omega-3 fatty acids and supplements at the stores.
But they're really expensive right now, so they're not being used as salmon feed.
But hopefully, that will change in the future.
If farmed fish were being fed algae-based omega-3,
well, Paul says that would be a game changer for the planet.
You know, I think there are a lot of people out there who like never want to eat a farmed fish, right?
And they've heard all these bad things about aquaculture.
But what I realized in the course of this book was that we could conceivably produce fish and shellfish using the fraction amount of carbon and a fraction amount of the energy, and just generally have this source of protein that was much greener.
This is a change for a fish guy like Paul.
He spent most of his life and career as a writer focusing on wild fish, but as he wrote this book, he came around to a new idea.
Maybe it's a better idea to grow algae on land and use those algal omega-3s to feed farmed fish and leave more wild fish fish in the ocean.
Maybe by growing marine omega-3s on land, we can have our fish, farmed fish, and healthier oceans too.
Interestingly, you know, I started this book with this idea of trying to understand what the miracle supplement was, but I came away from it being like, huh, the sea and the products that we could get from the sea could completely reshape the way that we eat and make our footprint on the planet much, much gentler.
But in the meantime, meantime, truly, my hot tip is to dissolve anchovies into all your sauces.
It's just salty umami deliciousness, no excess fishiness.
Paul actually has even more recipes to help you love oily fish in his book, The Omega Principle, which we have a link to on our website, gastropod.com.
Thanks to Paul Greenberg this episode, and also to Joanne Manson of Harvard University, and to the Sloan Foundation and the Burroughs Welcome Fund for supporting our science and health reporting.
Do not forget to go to gastropod.com/slash birthday to vote for your favorite episode for our birthday special.
I cannot wait.
I live for birthday cake.
This month on Explain It to Me, we're talking about all things wellness.
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