Macro partitioning
Western diets should reduce the n-6 to n-3 fatty acid ratio from the current 10-25:1 to approximately 1-2:1 to support cardiovascular health, normal development, and homeostasis.
Shift your fat sources. Reduce intake of corn, soybean, and sunflower oils (high in n-6) and increase sources of alpha-linolenic acid (ALA) like flaxseed, canola, and walnuts, while incorporating marine sources of EPA/DHA. Aim for a dietary ratio of n-6 to n-3 closer to 4:1 or lower, rather than the typical 15:1 found in Western diets.
Today this ratio is about 10 to 1:20 to 25 to 1, indicating that Western diets are deficient in n-3 fatty acids compared with the diet on which humans evolved... A balanced n-6/n-3 ratio in the diet is essential for normal growth and development and should lead to decreases in cardiovascular disease and other chronic diseases and improve mental health.
Why this rating
The paper synthesizes observational, animal, and clinical trial data, though it is a review/symposium paper rather than a single primary RCT.
Source
Human Requirement for N-3 Polyunsaturated Fatty Acids
Artemis P. Simopoulos · Poultry Science · 2000
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →