Recently, this older paper received some renewed attention and deservedly so as it explains why many nutrition studies underestimate the role of diet in disease.
Here is a recent analysis of it...
http://nutritionfacts.org/video/when-lo ... high-risk/
And here is the original full text paper...
http://ije.oxfordjournals.org/content/30/3/427.long
The points made in this paper are important and one the WFPB community has made many times, as I have in this forum. If an entire population is sick, then the range of “health” may not be sufficiently broad to establish a significant association.
Most of us are familiar with the point the paper is making in regard to fat and saturated fat. We know that many of the popular studies criticizing the "low fat" diet have 2 main problems,
1) no one in the studies actually lowered their intake of fat enough below the threshold to really see a difference. So, the range of fat from the high to the low was not much different and the low was not really very low at all.
2) Low fat is only one component of the diet recommended here and many of the subjects in these papers not only didn't really lower the amount of fat they were consuming, they also continued to eat a diet that was unhealthy in many other ways.
We see the same thing in the studies on saturated fat. The actually reduction in saturated fat we see in many of the papers is minimal and it is not lowered below the amount we recommend it to be below. In addition, the saturated fat is often replaced with other unhealthy items (junk food, oils, trans fat, refined flours, sugars, etc), that we would also do not recommend. So of course, they do not see the benefits we do.
However, if we understand these issues, then we also have to understand the converse issues and how they apply (or don't apply) to us.
This is another point I have been making here again and again and many of you will be familiar with it in regard to the the studies on kale, walnuts, and other reductionist approaches often promoted in the WFPB world. Just because a study (or a few studies) show some minor benefit to the consumption of a food in an unhealthy population when it replaces something unhealthy (saturated fat), or when added to a population that is eating almost no healthy foods, this means absolutely nothing to someone who is already following this way of life and already leading a very healthy lifestyle and consuming a very healthy diet. However, it may lead some of them to believe that replacing a sweet potato with walnuts will product the same benefit seen in the study.
In other words, if there is a study that comes out on oatmeal, and shows that in someone eating a typical American diet, if they change from consuming a typical American breakfast to one of whole grain oatmeal, they lower their cholesterol and blood sugar numbers. And, the more oatmeal the consume (up to a certain point), and the more days per week they consume it, the greater the benefit.
However, this does not apply at all in any way to any one who is already following the principles and guidelines of this way of life. If one is already following this way of life and consuming a breakfast of oatmeal (or other intact whole grain), adding in more oatmeal (&/or having it more often) is not going to further lower their cholesterol and blood sugar.
So, while many nutrition studies underestimate the role of diet in disease when looking at a typical population, many studies also greatly overestimate the role of a specific food in a diet when trying to apply the benefit seen in a sick population to those already following a healthy low fat, WFPB diet.
This forum is full of examples of this and for those who want to read more about this, the following specific threads go through several specific explanations of this...
I discuss the issue in general in this specific post...
viewtopic.php?f=22&t=28413&p=429750p429750
In this longer thread, I discuss the issue in detail and apply this principle using the example of kale, leafy greens and wild foods
http://www.drmcdougall.com/forums/viewt ... 22&t=28413
In this thread, I apply the principle using the example of resistant starches
viewtopic.php?f=22&t=29658
In this thread, I apply the principles using the example of meal frequency
viewtopic.php?f=22&t=26337
In this article, I discuss and apply the principle using the example of fructose
http://www.jeffnovick.com/RD/Q_%26_As/E ... d_You.html
In this thread, I discuss and apply the principle using the example of nuts
viewtopic.php?f=22&t=40295
In this thread, I discuss and apply the principle using non-starchy vegetables
viewtopic.php?f=22&t=42701
In Health
Jeff
