The next study on our tour of S-T and K's paper that "exonerated" SFA in coronary artery disease is an analysis of the data collected in the health professional's follow up study done at Harvard.
Once again, we see a homogenous population with very small differences between groups. In this case, US physicians, followed for six years. Dietary records were biennial FFQs. I remember one of my professors was in the study when I was in medical school. scholar.google.com/scholar_url?ur…
At least this population did show a reasonable variance between first and 5th quintiles. The lowest percentage SFA was still higher than the NCEP step 1 diet for CVD however. Yet there was a near doubling of SFA % between the groups. 
In addition, the incidence of hypertension and high cholesterol were HIGHER in the group that ate the least SFA at baseline. This may be due to reverse causation, in that those who had been told they had those conditions were adjusting their diet.
Even more interesting, sweets were consumed at the highest rate by those who also consumed the most SFA. This is a common confounder and not well-discussed. Not only individuals but also societies tend to increase both as economics allows.
This study showed nearly linear, stepwise increase in risk of both heart attack and death from heart attack with increased SFA. They then adjusted for cholesterol, age, blood pressure and fiber intake and those associations went away. This was also true for trans fatty acids.
To start with TFA, in the base consumption group there were 27 fatal MI's, in the highest group there were 56, p = .0005 age-adjusted. In the SFA group again 27 in the base but 66 in the highest with p = <.0001 age-adjusted. With more adjustment both attenuate but SFA stronger.
So HPFUS shows when you take SFA at 7% of energy at baseline and double it, even in a population with objectively higher BP and lipids at baseline, you nearly double cardiac events. The risk is attenuated by controling for a dependent variable, cholesterol, but this isn't legit.
I will count HPFUS as yet another one of the studies that actually showed significant risk to SFA in the S-T & K paper. Tomorrow we look at the Lipid Research Clinics Study.
