Saturday, January 22, 2022

So you want some DHA? Chickens in Norway

Again via twitter, Tucker retweeted a thread which included the link to this paper

Increased EPA levels in serum phospholipids of humans after four weeks daily ingestion of one portion chicken fed linseed and rapeseed oil

Over the years I keep coming back to this plot

which comes from another paper:

It shows, very clearly, that in rats both linoleic acid and alpha linolenic acids are equally efficacious at suppressing the conversion of ALA to DHA. Given 1% of energy in the diet as ALA then copious amounts of DHA are produced, just so long as the LA proportion of calories is less than 2% of the total. Never mind the ratio. Avoiding PUFA will generate DHA from ALA provided a basic minute minimum of ALA is present in the diet, somewhere around 1% of calories. Over at the right hand side of the plot we can see that even drinking 12% of your energy intake as ALA will not generate significant DHA if you are up in the cardiological nirvana of 16% of energy as LA.

That is in rats.

Chickens superficially appear to be somewhat different.

Switching from soybean oil to a rapeseed/linseed oil mix in the diet increases DHA in the breast meat. Soybean oil gives 14% of lipid as DHA, rapeseed/linseed gives 21%. Of not very much fat in breast meat so the amounts are small in total, but still highly statistically significant.

So ALA in food bumps up DHA in muscle. Of chickens.

This is what the chicken diet looked like, with annotation to give the fat percentage of total calories and the LA and ALA percentages of total calories in the diet, crudely:

We can overlay the chicken diet very approximately, on the rat plot to get this:

which, not surprisingly, suggests that the DHA production in the "high" ALA diet (blue) is actually more influenced by the reduction in LA. At 4% LA we could equally have had ALA at 1% of calories and still got a lower value for DHA than we did by having LA down at 2% of calories.

Might this work for humans too? Could adding ALA to our diet improve DHA availability, with all of what that entails for improved brain development and cognitive function. Just by avoiding LA and maybe drinking a little (traditional) varnish? The study didn't ask this. Instead they fed the above chicken to some humans. Either omega 3 enriched or omega 6 enriched.

This actually dropped DHA in the participants' plasma phospholipids in both groups. Admittedly not by much, so the change was neither statistically nor biologically significant. But it dropped. I would hazard a guess that the chicken simply displaced a richer source of ready-formed DHA from the diet, the tiny amount in the breast meat would do nothing per se. I believe Norwegians consume a certain amount of fish, unless they're given free chicken to eat. 

The rise in EPA must have made the authors happy that something positive came from all of that work. But I don't think you can build a brain out of EPA, DHA looks to be the molecule for that.

Ultimately pre-formed DHA does not look to be necessary for brain development if you have a modest supply of ALA from (grass fed, possibly large) animals and avoid consuming significant amounts of LA. This appears to hold true for rats, chickens and I expect for humans.



cavenewt said...

Grassfed is significant for ruminants? I believe in the past you've said that all the processing that goes on in ruminants' multiple stomachs saturates a lot of the polyunsaturated fats from a subpar diet. Or is it something to do with ALA specifically?

JustPeachy said...

Just as an aside, I used to have a small flock of chickens. Best eggs ever. My Dad ordered a bunch of flaxseed once for his digestion, and didn't find out until he got them that they were whole seeds, not the ground up kind, so he couldn't use them, and gave them to me. I gave a generous scoop to the chickens now and then. Chooks liked them, but every time they ate a pile of flaxseeds, it made their eggs taste and smell *fishy*. It was really off-putting.

Peter said...

cave, I was thinking of mammoths! Real human food, until we ate them all. Clearly ruminants are our best substitute. Preferably fat ones.

Justpeachy, sound delightful!


LA_Bob said...


I know people who take flaxseed (for O3, you know) in lieu of fish oil capsules, because they don't want "fishy"-smelling breath. Oh, the irony!

Mat said...

Does that suggest, that potato and Mcdougal's diets are good in terms of DHA?

Peter said...

Sounds plausible to me. You do need that 0.5-1.0% ALA Might be hard if total fat is < 10%) but getting fat low enough should allow DHA production. Bear in mind that if you get fat down to 10% of calories but most of that is plant derived omega 6s you're still fcuked on an LA basis...


Tucker Goodrich said...

"Ultimately pre-formed DHA does not look to be necessary for brain development if you have a modest supply of ALA from (grass fed, possibly large) animals and avoid consuming significant amounts of LA. This appears to hold true for rats, chickens and I expect for humans."

Yes, there seems to be selection pressure in humans, both for (Asian Indians) and against (Inuit/Eskimos).

"Eating green could be in your genes"

Peter said...

Yes, which leaves an interesting set of questions. In the absence of seafood, was mammoth fat adequate for humans? Did they need mammoth brain for the DHA or did they optimise desaturase/elongase? Loss of DHA synthetic ability seems trivial for the Inuit, why preserve un-needed genes when the diet is loaded with DHA? There is no "pressure" as such. For vegetarians there is pressure. They need DHA and there will be a spread of ability within the population for desaturase/eleongase ability. Positive selection pressure means the lucky ones survive to reproduce best. The other end of the distribution don't. They suffer pathology and become under represented in the population. Positive selection pressures are not very positive for the failures! Evolution is cruel.

Clearly a different set of pressures were present as we adapted to carnivory, at least those are probably long settled...

I guess rats are fine as they may have slightly lower DHA requirements as they're not terribly encephalised cf humans. And are well adapted as seed eaters too.


Gyan said...

People have been over-consuming LA for two generations now but there aren't reports of under-formed brains in newborns anywhere.
And there is the so-called vegetarian gene: the Fatty Acid Desaturase (FADS1) gene is associated with the synthesis of FADS1 protein, shown to be associated with the conversion of shorter chain fatty acids to longer length active forms. Found with great frequency in Indians.
"Analysis using data from the 1,000 Genomes Project similarly found the vegetarian allele in 70 percent of South Asians, 53 percent of Africans, 29 percent of East Asians and 17 percent of Europeans." (

Plenty of Indians barely consume any pre-formed DHA, replying on conversion from ALA and simultaneously consuming plenty of LA as well. They aren't the fittest people on the earth but have no problem in having children.

Peter said...

Gyan, why should they have under formed brains? All that's needed is suboptimal function. It may or may not be labelled as such in India but in the UK ADHD is endemic and very, very common.

And while there may be no fertility effect in two generations of adults, any current kids coming up with DMT2 in primary school (yes, they happen) may well have issues with fertility in their 20s.

Usually evolution works more slowly than this but industrialisation is relatively new.


baggirl said...

new twist (at least in my simple mind) for contemplating shellfish allergies

Passthecream said...

Peter "Usually evolution works more slowly than this but industrialisation is relatively new. "

I live in a zone where plagues of grasshoppers and plagues of mice are relatively common. During a serious mouse plague the mice are less intelligent than usual, less lively and less likely to run away. There are zillions of them everywhere and they quickly run out of good mouse-quality things to eat so they chew on anything they can get their teeth into and are deeply malnourished. These plague events are most likely the result of rapid environmental degradation due to inapropriate European agricultural and land management practices for the last 200 to 300 years in a very fragile, previously stable ancient environment.

I see the current human plague in a similar light while also being a small part of it. I hope to evolve a bit more quickly and sidestep the main rush, but?

I read that the reason a plague of grasshoppers (locusts) keeps moving across the ground is because if any of them stop moving, the grasshoppers coming up behind will eat them. That is some sort of useful metaphor I suppose.

karl said...

Right now, I'm wondering what a mammoth burger would taste like.

I read a lot of papers on fish oil re CAD. The best bit is it might act as a weak blood thinner - reducing clotting. BUT - there is a lack of papers using high dose fish oil - and some of the papers were obviously designed to not find an effect (only patentable interventions are sought). So my take is after all these years I still don't know if fish-oil is good for CAD.

karl said...

One last bit - OT

I'm looking at CQ10 supplement claims - I'm thinking again that it might have unintended consequences - disrupting the normal function of the ETC.. What would be the effect of too much CQ10?

Also - a lot of people are taking rather high dosages of melatonin - and again - might mess with the ETC. What might the long term effects be?

Melatonin in Mitochondria: Mitigating Clear and Present Dangers

bike said...

The paper presents a case report of a patient who has been using the Kwasniewski diet for 10 years, admitted to the Silesian Center for Heart Diseases in Zabrze, diagnosed with a heart attack without ST segment elevation.

bike said...

"The LCDs subjects were members of local supporters belonging to a nongovernmental society called the All-Polish National Association of Optimal Brotherhoods. They declared that they had maintained an LCD for at least 3 years."

"Surprisingly, the increased fat oxidation occurring in the LCDs subjects did not change the content of their body fat in comparison to individuals on the MDs."

bike said...

In the blood serum of people with HT using the 'optimal' diet, the MUFA, n-6 PUFA, PUFA/SFA ratio was lower than the reference. A high percentage of n-3 was observed, which may have a protective effect in the case of hypertension.

karl said...

What if CAD isn't about lipids? Everyone has a bit of Lp(a) - some of us more. If one is in the clot happens first camp - then understanding the interaction between platelets and apo(a) would seem to matter.

The only connection is that apo(a) diverts LDL from moving lipids - to moving apo(a) - The complicating factor is there are a lot of isoforms of apo(a) - different number of kringle repeats etc.

The drugs they are selling don't lower apo(a) - thus the research mostly stopped - not profitable if people look there.

There is this very much wrong and false narrative that proteins are designed - they are not - they evolved. This means they don't have to have single functions. Is LDL for moving lipids? Part of the immune system? For moving apo(a)? We have to stop looking at biology as engineered/designed systems. Someone locked into the idea that LDL was created to move lipids will have no chance of understanding what is going on. Biology is the history of environments that could hold life. Yes - it is much more complex that the narratives suggest.

Then couple this with homeostasis - again not designed, but evolved. In biology it is mostly assumed that the feedback loops are linear(not often), proportional(not always), and simple (just wrong). There is no interest in complex loops - say PID or chaotic or pulsive or even more complex. They can be hugely complex as long as it works. No engineering review to simplify the design. The reality is most loops are nested and redundant - this reduces the lethality of single point mutations. Any idea that medicine is doing more than a 'black-box' approach to drug treatments is silly - they are not able to understand the underlying complexity. They have raised 'hand-waving' to a high art form. This leads to a huge diversity of medical terminology that may or may not mean the same thing to different researchers. What it means is that many ideas are not actually available for the public to grasp - even if the concepts are rather simple.

Narratives are selected to make grant money move or sell a product. If you want to understand biology, one first has to understand the corrupt system - why so many papers are so useless and poorly designed studies.

Passthecream said...

Does the Optimal diet specifically aim to avoid pufa or mufa?

Peter said...

bike, yes OD is moderate PUFA, not ultra low. Which may explain certain problems.

Pass, no, it specifically avoids vegetable oils and margarines but doesn't avoid pork. Having said that European pork can come through as low as 9% LA in some papers. But never the less OD is not ketogenic so is should be less tolerant of LA than more ketogenic prescriptions such as PKD, which also allows (European) pork.

karl, "What if CAD isn't about lipids?" LOL, need emojies!


Passthecream said...

At the risk of furthering a cultural stereotype the mention of pork versus LA content leads to an interesting coincidence concerning a part of the world where pork consumption is high, solar UV is high and people with light skin colour make a big effort to keep the sun off their heads, arms and everywhere, namely south-east Asia.

Interesting that is, if you believe as I do that there is a strong correlation between sunburn and LA intake.

Passthecream said...

I recall that lamb has one of the highest ala contents amongst animal sources. If you could afford it Kiwifruit seed oil is approx 62% ala but last time I looked it was selling for approx $500 au per litre The seedy portion of a typical kiwi has approx 130mg of ala. You could just eat the central seedy part and give the fleshy part to a friend.

Captain Sunset said...

Peter, Poly v Saturated? Not the correct place to post this but, it's interesting: Well, for me anyway, but I'm sure most of your readers are well up to speed on this.

Unknown said...

I've wondered for a while if we might be missing some important nutrients that we evolved to get from mammoths (and maybe other megafauna) since we ate them all.

cavenewt said...

Cap'n, thanks for the link to the fascinating reading of "The case of the missing [Sydney Diet Heart Study] data" at Shades of Ancel Keys' basement! (Well, it was a co-author's basement.)

Ramsden makes a hobby of doing research archaeology. "Records Found in Dusty Basement Undermine Decades of Dietary Advice"

Highly recommended these days, especially in light of all the pearl-clutching about Science™. In a comment thread on Slate I was complaining about the accelerating trend toward dogmatic science and someone replied to me "The point of science is to build knowledge and determine truth." OK, I guess plate tectonics is out. Ditto neurogenesis in adults. Etc.

Passthecream said...

Ta for that link. Reading the data tape without destroying it would have been a challenging exercise.

This quote "Omega-6 Fats Linked to Increased Risk of Heart Disease."

Plain and simple. Would be a perfect title for a blog article by either Peter or Tucker.

Passthecream said...

Looks like hippoburgers are go:

Coming to a hippodrome near you, soon!

cavenewt said...

Slightly OT but tangential. This sounds fascinating: "Most Complete Simulation of a Cell Probes Life’s Hidden Rules"

'The cell in question is a lab-made “minimal cell” that teeters on the line between life and non-life, carrying a limited number of genes, most of them necessary for survival. By replicating the known biochemical processes happening inside this very basic cell and tracking all the nutrients, waste, gene products and other molecules moving through it in three dimensions, the simulation brings scientists closer to understanding how the simplest life form sustains itself and reveals some of the bare-bones requirements of life.'

I checked out the researchers' article in the journal Cell. "Fundamental behaviors emerge from simulations of a living minimal cell"

I guess mitochondria are not fundamental to cell behavior, because the word is not mentioned once. Curious.