LDL Cholesterol = Bad? Not Quite That Simple

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.

Did Krauss’ research make him a socially awkward penguin in the AHA?

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.”

Dissecting Heart Disease Like a Boss

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.”

Cause you’re in the low beef study group dude

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

2) http://www.npr.org/templates/story/story.php?storyId=15886898

3) http://www.meandmydiabetes.com/2012/04/17/ron-krauss-saturated-fat-red-meat-it-depends/

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Mayo Without Eggs? Must be the Mayo Clinic!

Eggs. People either fear them or think they are egg’cellent. Okay okay I won’t egg you on with anymore puns (oops!). In any case, TheFatNurse has parents who seem to think egg yolks are heart attacks waiting to happen due to the cholesterol content. Even the respected Mayo Clinic agrees, eggs should be limited via the 300 mg per day rule.

“One large egg has about 186 mg of cholesterol — all of which is found in the yolk. Therefore, if you eat an egg on a given day, it’s important to limit other sources of cholesterol for the rest of that day. Consider substituting servings of vegetables for servings of meat, or avoid high-fat dairy products for that day.”

“Although eating too many eggs can increase your cholesterol, eating four egg yolks or fewer on a weekly basis hasn’t been found to increase your risk of heart disease.”

Wait is their suggestion to max out on 4 eggs a week? TheFatNurse sometimes eats 4 eggs just for breakfast! More importantly, TheFatNurse thought it caught the Mayo Clinic in the shackles of irony since “The Mayo Clinic Diet” has eggs as the main part of its diet!

“The origins of the Mayo Clinic diet are unknown and, as the prestigious Mayo Clinic has declared time after time, this diet has nothing to do with them. The diet’s main component is egg, since it advises the consumption of between 4 and 6 a day “

Alas…that would have been too easy…but there still is irony yet! After all, what is one of the main components of Mayo…EGGS!

So where did this idea of egg consumption being harmful come from? It all goes back to the controversial but often accepted medical “fact” of the lipid hypothesis where eating saturated fat raises cholesterol and cholesterol causes heart disease. For a brief history see below:

So what does some of the current medical literature say on egg consumption?

“Several studies have examined egg intake and its relationship with coronary outcomes. All but one failed to consider the role of other potentially confounding dietary factors. When dietary confounders were considered, no association was seen between egg consumption at levels up to 1+ egg per day and the risk of coronary heart disease in non-diabetic men and women”

From the Journal of the American College of Nutrition *TheFatNurse only read the abstract

“Multivariate models adjusting for health, lifestyle and dietary factors indicated that ‘high’ egg consumption (7 times/week v. ,1 time/week) was not associated with significantly increased CHD mortality (HR51?13, 95% CI 0?61, 2?11 (men); HR 5 0?92, 95 % CI 0?27, 3?11 (women)…We did not find a significant positive association between egg consumption and increased risk of mortality from CHD or stroke in the US population. These results corroborate the findings of previous studies.

From Public Health Nutrition *TheFatNurse only read the abstract

“During a median follow-up of 6.1 years, 91 new confirmed cases of CVD were observed. No association was found between egg consumption and the incidence of CVD (HR: 1.10, 95%confidence interval: 0.46–2.63) for the highest versus the lowest category of egg consumption

From the European Journal of Clinical Nutrition *TheFatNurse only read the abstract

there is little evidence from epidemiological studies for associations between dietary cholesterol or the consumption of cholesterol rich foods and cardiovascular disease risk, or from intervention trials for major effects of dietary cholesterol on blood cholesterol levels. By contrast, evidence is emerging from epidemiological studies that consumption of eggs is associated with cardiovascular disease in diabetics, and from intervention trials that dietary cholesterol has greater effects on blood cholesterol levels in insulin resistant people. Since insulin plays a role in cholesterol homeostasis, these are not surprising findings.”

From Lipid Technology *TheFatNurse only read the abstract

“Our analysis shows that the combination of modifiable lifestyle risk factors accounts for less than 40% of the population CHD mortality. For the majority of U.S. adults age 25+, consuming one egg a day accounts for <1% of CHD risk. Hence, focusing on decreasing egg intake as an approach to modify CHD risk would be expected to yield minimal results relative to changing other behaviors such as smoking and other dietary habits.”

From Risk Analysis *TheFatNurse only read the abstract

The European countries, Australia, Canada, New Zealand, Korea and India among others do not have an upper limit for cholesterol intake in their dietary guidelines. Further, existing epidemiological data have clearly demonstrated that dietary cholesterol is not correlated with increased risk for CHD. Although numerous clinical studies have shown that dietary cholesterol challenges may increase plasma LDL cholesterol in certain individuals, who are more sensitive to dietary cholesterol (about one-quarter of the population), HDL cholesterol also rises resulting in the maintenance of the LDL/HDL cholesterol ratio, a key marker of CHD risk… The lines of evidence coming from current epidemiological studies and from clinical interventions utilizing different types of cholesterol challenges support the notion that the recommendations limiting dietary cholesterol should be reconsidered.

– From Current Opinion in Clinical Nutrition & Metabolic Care *TheFatNurse only read the abstract

“While dietary cholesterol, of which egg yolks are a major source, was once thought to play a primary role in determining plasma cholesterol levels, and therefore CHD risk, scientific opinion appears to be shifting to the belief that it may have a negligible effect in most healthy people.

– From Today’s Dietician

Bottom Line: TheFatNurse thinks you get the point. There are plenty of  studies you can find showing the association between eating one egg or more daily and heart disease being murky.  So does this mean you should go out and eat eggs for breakfast, lunch and dinner while downing egg nog and ramos fizzes in between? No of course not! That’s GROSS! However, egg consumption could be an interesting topic to bring up with your primary care provider who would know you, your physiology and any underlying pathologies you may have if egg consumption worries you. Some pathologies such as insulin resistance may make high egg and dietary cholesterol harmful as suggested by some studies.

To be fair, lots of the studies considered 1-2 eggs a day as a high daily egg consumption. If one were to just eat only 1 egg and adjust for the 300 mg daily allowance as the Mayo clinic suggests then you will still be within their guidelines even with them quoting 4 eggs a week or less from studies. TheFatNurse only selected the Mayo Clinic as a source of standard egg guidelines because TheFatNurse likes the taste of mayo. The egg topic is more of a primer to ask an even grander question: Is it really clear that cholesterol causes heart disease?

WHAT…I know…this was probably your response:

Just keep an open mind! Read some of TheFatNurse’s cholesterol related postings, browse some of the links in the Dispatch section. Need something visual first to open your mind? Take a look at this graph from the famous Framingham Study:

Unless they had hypercholesteremia, coronary heart disease effected people almost at the same rate despite their cholesterol levels

Intrigued? Browse some past and future cholesterol related postings, check out the Dispatch link or view this University of South Florida video which does a pretty good general overview of the controversy of cholesterol (you do not have to agree with his diet choice per se, just listen to the references he brings up on cholesterol):

Unintended consequences of Medical Dogma

So what do people know about heart disease? Well that is often determined by what their healthcare providers tells them. And what is their healthcare provider likely to tell them? Well, unless they constantly keep up with the latest research, they are likely to tell them the knowledge they were educated with themselves. For myself, I was taught to inform patients that they should eat a low fat (especially of animal fats) and low cholesterol diet (along with low sodium but that’s for another discussion) if they wanted to reduce their incidence of developing heart disease. From my Pathology and Nutrition textbooks:

“A major intervention related to atherosclerosis is encouraging the consumption of a low-fat diet, with those fats being primarily polyunsaturated (from vegetable sources as opposed to animal). Additionally, exercise and weight control are effective in improving lipid profiles. Pharmacologic management of elevated serum lipids is encouraged as a prophylactic intervention”

“Saturated fats are of animal origin. Fats from plant sources usually are unsaturated fats and help reduce health risks (notable exceptions are coconut and palm oil).” 

By now this is common sense right? After all, everybody knows that eating fats is unhealthy and will clog your arteries. But in case you forgot, celebrity doctors like Dr. Oz was on the other day informing viewers that “cutting the fat in half saves a lot of lives.” So how do we know all this? There must be thousands of research studies that show consumption of fat and cholesterol is bad right? Actually…not really.

The connection between heart disease with cholesterol and saturated fat is often taught as eating saturated fat raises cholesterol (LDL) which ends up clogging your arteries. This connection is often cited as if it were unquestionable medical dogma but the evidence of this ever being clear cut is shaky at best. Much has been discussed at length about this by other medical professionals such as the bloggers in my dispatch link. If this is the first time you’ve heard about this, an entertaining documentary about the matter can be found in Fathead by Tom Naughton. For those who want more details, Good Calories, Bad Calories by Gary Taubes provides much more detail about the matter. So instead of going over the subject matter I thought I’d share my thoughts on the unintended consequences of this.

With everybody believing saturated fat and cholesterol are the culprits without solid evidence what has happened?

We now have supermarkets filled with low-fat options that substitute the fat with more carbohydrates when some research is showing carbohydrates as the original culprit.

We’ve developed drugs (Statins) which are now one of the most prescribed medicines that are believed to reduce risks of heart attacks since they lower cholesterol. However, if cholesterol was never a cause for heart disease, then patients have been taking a drug they have never needed while being exposed to adverse risks such as cognitive dysfunction and increased risk of diabetes from these drugs.

We can’t be objective because everything is viewed through this diet-heart hypothesis. A good example of this is the “best diets” list by U.S News which seems to have diets ranked upon how little saturated fat and cholesterol they compose of. It doesn’t bother asking whether the assumption of saturated fat and cholesterol being bad is valid in the first place.

It’s created an obesity stigma where people who can’t lose weight are viewed upon as lazy, incompetent and lack will power. However, if carbohydrates are the original cause, their obesity may have been contributed because they were informed to eat less fat and more carbohydrates!

Defining cholesterol and saturated fats in this manner without reexamining them focuses a lot resources used in research on potentially the wrong cause and treatment.

More importantly, if everything was based on the wrong hypothesis, then the rises in obesity, diabetes, childhood obesity, heart disease, metabolic syndrome, and etc were the cause of unintended consequences!

“Artery Clogging-Saturated Fatty foods” like Chocolate are associated with…thinness?

Dr. Beatrice from the previous post and her team have found an association between lower BMI and increased chocolate consumption.

The results actually shouldn’t be that surprising since a lot of studies on chocolate have been coming out showing associations with decreased heart disease, better lipid profiles and decreased blood pressure.

Anyways lets take a look at the actual study itself. http://archinte.ama-assn.org/cgi/content/extract/172/6/519

Looks like they found 1018 men and women between 20-85 from San Diego without any cardiac or diabetes. However, to get their results they used food frequency questionnaires. Hmm….how reliable are these? However, food questionnaires are constantly used to support studies showing the usual low-fat advice so its fair game in that regard. Their results showed a 99% chance greater chocolate consumption frequency was linked to lower BMI. In addition, Chocolate consumption was also 99.9%  likely linked to greater calorie and saturated fat intake as well (duh!). By the way, being linked or associated with something doesn’t imply causation! These results are intriguing since we would probably assume the higher amount of calories and saturated fat intake would mean higher BMI.

So what happens when a study raises the ideas of a food people love and crave being associated with a lower BMI? OMG CHOCOLATE MAKES YOU THIN! LEMME AT IT! OUT OF THE WAY! BUY STOCK IN HERSHEY NOW! 

Relax, the people in the study ate chocolate on average 2 times a week (SD=2.5) and exercised 3.6 times a week (SD=3.0) don’t over do it! Again, the more intriguing aspect is the higher amount of calories and saturated fat ingested while being associated with lower BMI which runs contrary to what we would think based on traditional low fat advice.