Historical perspectives on the impact of n-3 and n-6 nutrients on health, by Bill Lands.

Here's Fig. 1. from http://www.sciencedirect.com/science/article/pii/S0163782714000253

Relating tissue HUFA balance with blood cholesterol and heart attacks. Results from the 25-year follow-up in the Seven Countries Study [35] were discussed in an earlier review [10] which noted that “Food energy imbalances which elevate blood cholesterol may be fatal only to the degree that omega-6 (n-6) exceeds omega-3 (n-3) in tissue HUFA. Such evidence raises questions about the hypothesis that blood cholesterol levels cause CHD.” Northern Europe and Southern Europe have abbreviations “No.” and “So.”, respectively. The Figure is reprinted with permission of the publisher.

Hat-tip to Dr. Thomas Dayspring for Tweeting this review.

Fig. 1 is interesting, as it shows a significant association between 25-year CHD mortality and Serum Total Cholesterol for every region except Japan. What's different about Japan, compared to Northern Europe, USA, Serbia, Southern Europe & Crete?

According to Measuring Blood Fatty Acids as a Surrogate Indicator for Coronary Heart Disease Risk in Population Studies , Philippines & Iceland have lower % linoleic acid than Japan. Where's the CHD vs TC data?

Could another difference be that the Japanese eat rice, a relatively intact grain, instead of foods made from wheat grain dust (i.e. flour) as their main source of dietary carbohydrates?

See also Using 3–6 differences in essential fatty acids rather than 3/6 ratios gives useful food balance scores , and Omega 3-6 Balance Score.