Continuing with this week’s HDL mainstream news, TheFatNurse thought you should be aware of a man named Dr. Ronald Krauss and his work on LDL cholesterol (you know, the “bad” one). In the 1980’s, Dr. Krauss was one of the prominent researchers to point out that many studies showed those with heart disease and those without had almost the same LDL levels.
“If you look in the literature and just look at the average coronary patients…their LDL-cholesterol levels are often barely discernibly elevated compared to patients who do not have coronary disease.” (1)
So how prominent a figure was he? He was once the chairman for the nutritional committee for the American Heart Association (AHA) – The same AHA that was recommending low fat intake resulting in more carbohydrate intake as a consequence in order to decrease heart disease. This is ironic, as mention by Gary Taubes in Good Calories Bad Calories, since Krauss had found associations between carbohydrate increase and the risk of Heart Disease.
Additionally, Krauss also found substituting fat with carbohydrates increased small dense LDL particles which are associated with increased heart disease compared with the not as dense LDL particles from saturated fat which is not as bad. (2) In a NPR interview (2007):
“…recommendations are now pushing hard for lowering LDL cholesterol by reducing fat and saturated fat…based on the assumption that it would improve LDL related heart disease risk. Our evidence is it doesn’t effect the dense LDL at all. Substituting carbohydrate for fat, a natural consequence of those recommendations will actually increase levels of the small LDL”
“…processed and refined starches and sugars that are the most deleterious metabolically…food that contain a lot of fiber…have a lot of bulk but not as much carbohydrates…this recommendation [eating more carbs rich in fiber] is very difficult in practice…[agree with Taubes in] considering all carbohydrates as potentially adverse.”
Much of Krauss’ work points to how much of the advice that is considered fact may instead be harmful to us. In an interview just last month (3):
“…we fed these low fat diets and reduced the fats by substituting carbohydrates, which was at that time and still remains the current paradigm, we really didn’t achieve what we had wanted to achieve…some improvement in the overall amount of cholesterol in the very small percentage of individuals who had very high amounts of small LDL particles in their blood already… the majority of people we studied, the high percentage of people who had the normal metabolic profile, with more of the safer, Pattern A, larger particle LDL, shifted into the riskier, pattern B mode when we reduced their saturated fat intake.”
Because of his work, Krauss is well known in the low carb community when they need supporting claims from a well established nationally recognized physician and researcher:
“…we were certainly concerned about increasing heart disease risk, so we turned our attention ultimately away from feeding higher carbohydrate, lower fat diets, to doing the reverse, to lowering carbohydrate and raising fats, and that’s where we intersected with the world of people very interested in very low carbohydrate diets.”
“[Interviewer] You’re saying that in people who ate more fat and less carbohydrate, and in fact, who ate more saturated fat, they had a little more total cholesterol fat in their blood, but it was mainly being transported in big, fluffy LDL particles, which are the kind that scientists who study heart disease consider pretty safe.
[Krauss] Yes. When people ate more fat and less carbohydrate, the number of small particle LDLs remained low, and switching from monounsaturated to saturated fat didn’t increase their number at all. In fact, when people switched from mono- to saturated fat in this study, the large particle LDLs might have gone up a little bit…the small particles went down. So by anybody’s current criteria about whats’s important for heart disease risk, saturated fat caused no increase in risk.”
What is interesting about the LDL particle theory is the debate on whether or not the size and density of the particles matter. Krauss seems to believe the smaller denser particles are more of a concern, whereas others believe it doesn’t matter such as Dr. Dayspring from last week’s post. As Krauss states:
“I and many of my colleagues would argue that the biggest concern is warranted when the number of smaller particles is high, not the larger ones.”
However, both viewpoints can be compatible based on numbers and the ability of the larger LDLs to carry more cholesterol:
“It’s definitely associated with lower heart disease risk if the cholesterol is carried in larger particles, and that’s because there are fewer of them”
Confused? Here’s a lecture from Dr. Tara Dall that might clarify things better:
So does Krauss’ work offers more support that you can eat all the saturated fat you want? After all in the same interview last month:
“…in our 2006 study, the blood work was better when feeding people higher fat diets, than…feeding them lower fat and more carbohydrates…keep in mind, this was in the setting of lower carb and a mixed protein diet, proteins from various sources from white meat and dark meat and chicken and fish and beef.”
However, you may recall TheFatNurse posting last month about another Krauss study that showed saturated fat could be associated with increased CHD risk if it came from high amount of red meat (all beef in that study). Krauss touches upon that study in this interview:
“…keep in mind, this was a very high beef diet. People were eating beef breakfast lunch and dinner. So this is really way outside of what we would ever consider to be a usual health practice. Maybe some people do it. But not many.”
Currently, Krauss is using these latest results to try and isolate the reason for excessive red meat being associated with heart disease. Whereas before someone might easily blame it on the saturated fat, Krauss believes it could be other dietary consumptions with the saturated fat in red meat. Is it the iron? That’s one idea from Krauss and TheFatNurse looks forward to seeing more from Dr. Krauss in the future.
Bottom Line: Dr. Ronald Krauss has been a pioneer in the field of dietary consumption and heart disease. His work throughout the years shows how science and nutrition are constantly evolving and we must never accept anything as fact until it’s been fully tested. When long held facts such as “HDL = good LDL = bad” or “saturated fats can cause heart disease” are no longer that clear cut, we as a society need to be open to reexamining these long held beliefs and begin research on new ones.
1) Taubes, Good Calories Bad Calories, page 170