Eyes, n-3 and overall lubrication

[Amazoniac]

I briefly commented with haidut about this issue today. I'm sharing because if anyone is experiencing such a thing, you might consider it:

I've stumbled upon studies on eye function, especially the retinal ganglion cell and intraocular pressure, suggesting that dietary n-3 are needed in order to improve its function. A common symptom with its deficiency is dry eyes, since n-3 are apparently involved in lubrication and mucus in general throughout the body.

For us that restrict PUFA, this is a real concern and relatively easy to treat. Oysters occasionally paired with saturated fats should provide enough for this purpose and at the same time won't be an excessive amount of the unsaturated fats.

Google it:
Dietary o-3 deficiency and IOP insult are additive risk factors for Ganglion Cell Dysfunction

 

[BingDing]

From what I've read about it, prenatal, infant and maybe developing children need 0-3 fats for eye development but it doesn't continue in adulthood. Though if oysters and melted butter would address the supposed need there's no reason not to eat it.

 

[Such_Saturation]

I think I will be sleeping just fine tonight...

 

[dd99]

From what I've read about it, prenatal, infant and maybe developing children need 0-3 fats for eye development but it doesn't continue in adulthood..

This is precisely what I can't figure out. Does my toddler need fatty fish? He seems to be thriving without it, eating a well rounded Peaty diet. The pressure from all sides is to feed kids omega 3 at every opportunity.

 

[Such_Saturation]

From what I've read about it, prenatal, infant and maybe developing children need 0-3 fats for eye development but it doesn't continue in adulthood..

This is precisely what I can't figure out. Does my toddler need fatty fish? He seems to be thriving without it, eating a well rounded Peaty diet. The pressure from all sides is to feed kids omega 3 at every opportunity.

Fish oil in the Observer: the return of a $2bn friend

 

[jyb]

From what I've read about it, prenatal, infant and maybe developing children need 0-3 fats for eye development but it doesn't continue in adulthood..

This is precisely what I can't figure out. Does my toddler need fatty fish? He seems to be thriving without it, eating a well rounded Peaty diet. The pressure from all sides is to feed kids omega 3 at every opportunity.

There is pufa in breast milk. I'm sure some of it is O-3. Or is the argument that we need more than that for this eyes health problem?

 

[Amazoniac]

The problem with bringing these subjects up is that people tend to reduce ad absurdum to disprove. But in this case, it's very subtle, maybe just consuming a whole food containing a bit of DHA and paired with saturated fats to balance the proportion of the meal. That won't exceed any restriction.
In one study they were mentioning the composition of tissues that require n-3, the retina being one of them. But the main concern in this thread is mucus and tissue lubrication. If you are experiencing any abnormality or discomfort it's something to consider..

 

[Amazoniac]

And regarding milk and PUFA, infants do seem to require some of it for development but that reduces greatly in adults. Our requirement might be to supply subtle function like the one mentioned here.

 

[tara]

Is most the PUFA in human breast milk just there because currently most women's diets are high in PUFAs? If the mother had always eaten a low PUFA diet, would there be much less in the milk? Lots of things can be in the milk because of mum's diet that aren't serving baby. Is there any evidence of lower PUFA breast milk from a healthy well nourished mother causing any difficulties?

 

[Amazoniac]

Perhaps it gets a bad conotation here but it's a matter of context and dose, like cortisol. I think that Ray Peat did a great job in defining a safe range. What I wonder is if there's an optimal amount - which is probably very low - or the less the better..

 

[tara]

Perhaps it gets a bad conotation here but it's a matter of context and dose, like cortisol. I think that Ray Peat did a great job in defining a safe range. What I wonder is if there's an optimal amount - which is probably very low - or the less the better..

Yeah - hard to know, since zero is not a testable possibility.

 

[Blossom]

Would mead acid possibly fill that role?

 

[Such_Saturation]

The problem with bringing these subjects up is that you are having effects you can't foresee on people who can't yet decide for themselves. How would you feel about coming to the world with unnatural blood and tissues just because some newspaper intern spent five minutes browsing Pubmed or something? These are not things that are easily undone.

 

[Tom]

According to http://www.ncbi.nlm.nih.gov/pubmed/1560329

DHA content was 0.14% of total fat in the milk of vegan mothers, 0.30% in vegetarians and 0.37% in omnivores. This would be about 200 mg DHA per 2500 kcal for vegan mothers. I haven´t seen any lower amount of DHA than that in human milk. 200 mg DHA especially for pregnant women seems to be the worldwide recommendation right now (and much higher for those with various diseases). According to one analysis 100 grams of oysters have about 300 mg DHA, 100 grams of shrimps around 150 mg DHA. 1 egg could have anywhere from 20 (grain fed) to 100 mg DHA (fish fed), depending on the feed. Arachidonic acid may actually be more of a concern on a very low PUFA diet than DHA. Even in eyes AA is normally found in almost as high quantities as DHA.

 

[jyb]

Is most the PUFA in human breast milk just there because currently most women's diets are high in PUFAs? If the mother had always eaten a low PUFA diet, would there be much less in the milk? Lots of things can be in the milk because of mum's diet that aren't serving baby. Is there any evidence of lower PUFA breast milk from a healthy well nourished mother causing any difficulties?

In general PUFA content doesn't seem to vary that much for a given product... You can raise a very happy cow, it will have similar pufa % content than a sick cow fed grains in a commercial farm. However there are important nutritional differences. Also, the composition of the pufa could vary. I don't have access to the study but... http://www.ncbi.nlm.nih.gov/pubmed/25557897

 

[Tom]

In general PUFA content doesn't vary that much for a given product, at least for the products I usually look at. You can raise a very happy cow, it will have similar pufa % content than a sick cow fed grains in a commercial farm. However there are important nutritional differences other than raw total pufa count so of course it doesn't mean much. Hormone content for example.

This is also largely my experience, however while Arachidonic acid content seems to be relatively fixed, whether it´s eggs or milk of vegans versus omnivores, or even cow milk/cheese, DHA can fluctuate considerably depending on feed. http://www.ncbi.nlm.nih.gov/pubmed/14676141

 

[tara]

Is most the PUFA in human breast milk just there because currently most women's diets are high in PUFAs? If the mother had always eaten a low PUFA diet, would there be much less in the milk? Lots of things can be in the milk because of mum's diet that aren't serving baby. Is there any evidence of lower PUFA breast milk from a healthy well nourished mother causing any difficulties?

In general PUFA content doesn't seem to vary that much for a given product... You can raise a very happy cow, it will have similar pufa % content than a sick cow fed grains in a commercial farm. However there are important nutritional differences. Also, the composition of the pufa could vary. I don't have access to the study but... http://www.ncbi.nlm.nih.gov/pubmed/25557897

But cows and humans are likely different in this respect, because ruminants have bacteria helping them convert PUFAs to SFAs, and we non-ruminants don't. That's why I'm thinking that human milk may be more influenced by mum's diet than cow's.

 

[jyb]

But cows and humans are likely different in this respect, because ruminants have bacteria helping them convert PUFAs to SFAs, and we non-ruminants don't. That's why I'm thinking that human milk may be more influenced by mum's diet than cow's.

There are slight differences in the composition of pufa and I'm sure very important differences in nutrition, but it does not mean that the total pufa weight changes that much across difference pufa diets. See:
http://www.ncbi.nlm.nih.gov/pubmed/23148871

 

[Amazoniac]

tara has a point, our digestive tract is much shorter so we don't modify too much the food that we consume before it gets absorbed, so we are probably more influenced by our diet compared to a ruminant. And this is the argument that Paul Jaminet makes over and over again in his work, that we should consume a diet that is close to our composition because it's going to be less demanding.

 

[Such_Saturation]

And this is the argument that Paul Jaminet makes over and over again in his work, that we should consume a diet that is close to our composition because it's going to be less demanding.

Hopefully not too close