The emerging picture on n-6 is that adequate intake is somewhere between 0.5% and 1% of calories with toxicity developing somewhere between 3% and 10% of calories depending on the amount of n-3 stored in the tissue.
The catch is n-3 is even more volatile than n-6, making safe forms of n-3 supplementation hard to find and placing limits on the amount of supplementation which can be safely consumed.
The 2015 “Scientific” Report of the Dietary Guidelines Advisory Committee recommended Vegetable Oil as the primary fat despite the fact estimated US consumption of n-6 PUFA is at 9% (probably a low estimate) and 10% is the high end for tolerance (and probably a high estimate).
There are identified mechanisms tying PUFA excess to cardiovascular disease, liver disease and obesity. These are strong ties (it will happen) not loose ties (it may happen). The only question is at what level and predictions for heart disease tie closely with observations. There are well documented increases in all three diseases since vegetable oil consumption increased.
Bill Lands: 2014 Review of EFA
Historical perspectives on n-3 & n-6 impact to health.
Healthy intake levels of n-3 & n-6
n-6 involvement in the development of cardiovascular disease.
n-6 and overeating in the development of cardiovascular disease.
Issues with dietary recommendations
Nutritionists View on n-6/n-3
Outstanding information on the hazards of PUFA perioxidation.
Followed by perplexing recommendations of mitigating the hazards with anti-oxidant supplementation and n-3 (which is even more volatile than n-6) supplementation.
Details on the original meaning of “essential” when it comes to n-3 & n-6 (necessary for growth rate and skin quality in mice) and details on how hard it is to develop a PUFA deficiency (answer: damage the intestines and place on a zero fat intravenous diet).
Out of Balance You Tube Video
Promotional video by a company selling seafood Seafood bias but well produced and some good info.
Links between PUFA excess and impact to mental health.
Ties in to the report which came out this week on a rise in death rate for middle age white males.
Impact to mental health back in 1972.