Since there is a modicum of interest, when time allows I'll be going through the studies referenced in Krauss & Siri-Tarino's paper. These studies don't have uniform results and it's important to allow for heterogeneity.
However, as it relates to heart disease specifically, it is important to understand the normal distribution. If something is truly mildly harmful, we would expect results of studies investigating it to show a few beneficial results, mostly harmful effects and a few neutral.
If something were really harmful, the skew would be away from ever showing beneficial effects. That said, I'll start with the first reference in S-T and K's paper, the Western Electric study. Published in 1981, it looked at 1900 men followed prospectively for 20 years.
No advice was given and the only dietary assessments took place at the start of the study and one year in. The average serum cholesterol in this population was 247! Yikes. Average person in the study got 16.7% cals from SFA. Yikes. nejm.org/doi/full/10.10… 
The study used the Keys and Hegsted dietary scores which combine the percent SFA, total dietary cholesterol and PUFA intakes into a score. They showed a positive significant association with the total score. SFA alone was associated with greater heart disease but p was .144.
Of note, the difference between the lower tertile and upper tertile was less than a single percent of SFA. So adding this study to their group for meta-analysis was a stroke of genius for the dairy-industry funded meta-analysis.
If we studied two groups of about 700 drivers each, one who drove 10,900 miles per year and another who drove 11,800 miles per year and showed no difference in crash rates, it would surely not be surprising or make us wonder if total miles driven/yr was a risk for crashes.
This will be a recurring theme in the analysis of these papers. Often a paper is cited where there is very little daylight between the best and the worst and so the study can't show much of a difference. This is why Seven Countries was important. It showed real differences.
That's all for today, but tomorrow I'll take a look at one of the oddest studies in the mix, the Honolulu Heart study.
