Looking for recent studies that prove the harmfulness of PUFAs

[barbwirehouse]

Anything released within the last decade?

 

[jyb]

If you're just looking for a few harmful effects of omega-6 pufas, then you'll find a huge amount of studies. For omega-3, probably a few but I remember at least one trial where they found it wasn't as useful as claimed.

 

[burtlancast]

Ray wrote omega-3 had been shown in the late forties to cause brain degeneration and yellow fat disease in farmed animals.

 

[schultz]

I encourage you to start going on Pubmed and reading through articles. Soon you will get good at knowing what to look for and what to search. Abstracts are good and all but personally I get the most value from the introduction which usually cites a lot of research that lead to other articles. You may already do this though!

You won't find any controlled human studies showing complete and direct "proof" of this. Firstly, every human in the study would have to comply and secondly it would probably cost billions of dollars. What you have to do is start putting little bits of information together to make a broad picture of things. Ray said something like "Putting bits together to make a meaningful puzzle".

For example:
If you look up lipofuscin in wikipedia the article says this...

Pathological accumulation of lipofuscin is implicated in Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, certain lysosomal diseases, acromegaly, denervation atrophy, lipid myopathy, chronic obstructive pulmonary disease, and centronuclear myopathy.

It also says...

It appears to be the product of the oxidation of unsaturated fatty acids

2 popular lipid peroxidation products are malondialdehyde and 4-hydroxynonenal. Search those in pubmed and it should give you a starting point.

Even the wikipedia article on malondialdehyde says this...

Malondialdehyde results from lipid peroxidation of polyunsaturated fatty acids... Reactive oxygen species degrade polyunsaturated lipids, forming malondialdehyde... Malondialdehyde reacts with deoxyadenosine and deoxyguanosine in DNA, forming DNA adducts, the primary one being M1G, which is mutagenic.

and the wikipedia article on 4-Hydroxynonenal says this...

4-Hydroxynonenal is generated in the oxidation of lipids containing polyunsaturated omega-6 acyl groups, such as arachidonic or linoleic groups, and of the corresponding fatty acids... they are being considered as possible causal agents of numerous diseases, such as chronic inflammation, neurodegenerative diseases, adult respiratory distress syndrome, atherogenesis, diabetes and different types of cancer.

In science papers it seems to be well known that PUFA's are unstable and damaging which always surprises me since people are always trying to get you to eat more of them to be healthy.

Anyway, I didn't link any studies but this article links to about 80 or so.

Hope that helps!

 

[burtlancast]

One convenient way by the industry to explain/deflect away the observed deleterious effects of both omegas-3 and -6, while re-emphasizing their "essentiality", is to point to the competitive inhibition between linolenic (omega-3) and linoleic (omega-6) acids in forming their respective derivatives DHA and Arachidonic acid.

An excess of one causes deficiency of the other, which causes "deleterious" effects.

Chris Masterjohn is very good at this game: http://www.westonaprice.org/health-topi ... -perilous/

 

[burtlancast]

Effects of n-3 fatty acids on growth and survival of J774 macrophages
http://www.ncbi.nlm.nih.gov/pubmed/10841044

15mg/ml of EPA killed over 90% of J774 populations.
Docosapentaenoic acid (DPA) was more cytotoxic than either EPA or docosahexaenoic acid (DHA). EPA was shown to be elongated to DPA.

Results demonstrated that EPA presented as a free fatty
acid killed a large proportion (>90%) of cell populations
in vitro whilst elevating levels of MDA by approximately
40% (as compared to untreated control cells) at a dose of
approximately 5 mg/ml (Figs 2, 4). The levels of EPA are
physiologically feasible, since other workers have demonstrated
that similar levels of EPA (7.6 ± 3.6 mg/ml) are
found in free fatty acid form in normal human plasma.23
The nature of cell death induced by EPA was shown not
to be apoptosis,
These observations imply that a necrotic pathway of cell
death was induced by EPA in the J774 cells.

There is evidence
that dihomogammalinolenic acid (20:3;n-6) and
arachidonic acid (20:4;n-6) are both appreciably cytotoxic
in other cell systems in vitro.35 Therefore, the possibility
exists that the cytotoxic effects of PUFAs may not necessarily
be specific to the n-3 class.

 

[haidut]

This study found omega-3 tied to getting highly aggressive prostate cancer.

http://www.nlm.nih.gov/medlineplus/podc ... 90313.html

"...The study’s 12 authors explain they could not discern if the risk of prostate cancer was derived from eating fish rich in omega-3 fatty acids (such as salmon or herring), or from fish oil supplements. Either way, the authors note the study suggests higher overall fish oil levels may pose a more significant prostate cancer risk than many persons realize. In an interview after the release of the study’s findings, the study’s lead author told HealthDay (and we quote): ‘fatty acids have been promoted as a blanket anti-chronic disease... ‘but nutrition is more nuanced, as is disease occurrence’ (end of quote)."

Also, the definition of yellow fat disease mentions that is caused by eating a lot of omega-3 foods such as canned tuna.

http://medical-dictionary.thefreedictio ... at+disease

Finally, see the attached screenshot from a highly referenced book on omega-3 fats.