Cholesterol. How many times you heard that word in the last month?
I bet that a lot.
Cholesterol seems to be everywhere. There is so much misconception about it that we decided to ask expert several questions.
Dr. Michael Miller is one of the leading cardiologists and serves as a Professor of Medicine at the University of Maryland School of Medicine .
You can find our short Q&A session below:
What is cholesterol?
Cholesterol is a waxy substance that is vital to life. It is an important structural component of our cells and is needed to make hormones such as sex steroids and Vitamin D . Without cholesterol, we would not make hormones that help to regulate our metabolism and breakdown of fat.
It looks like this:
Why is it important?
Cholesterol is involved in producing a number of important hormones that regulate our metabolism. Without cholesterol, we would not be able to absorb fat and would have problems with maintaining weight, healthy bones, mental health and normal sexual function.
Does good and bad cholesterol exist?
Just like water and oil don’t mix, cholesterol cannot travel in the bloodstream by itself. It needs to be packaged. Bad cholesterol refers to “LDL” particles that distribute cholesterol to our body tissues whereas good cholesterol, referred to as “HDL”, transports excess cholesterol out of our tissues and blood vessels. In truth, cholesterol is only bad if we have too much of it, as occurs when LDL cannot be effectively broken down. In these cases, excessive amounts of cholesterol in the bloodstream is scooped up by scavenger cells and these scavenger cells (or macrophages) form the cholesterol plaques that cause hardening of the arteries.
How to measure cholesterol?
With a simple blood test. It is recommended to do it in a clinic rather than using a home system. They are often inaccurate.
What is considered a normal cholesterol level?
A normal or “physiologic” cholesterol level is somewhere between 110 to 150 mg/dL
For every 50 mg/dL above 200, the risk of heart disease doubles.
What are the factors that impact cholesterol levels?
Genetic factors influence cholesterol levels. Eating foods that are high in saturated or trans fats also increase cholesterol. Foods that are high in mono (olive oil) or polyunsaturated fat lower cholesterol levels.
Do cholesterol levels relate to the thyroid?
Yes, an underactive thyroid can result in high cholesterol levels.
Does food rich in cholesterol affect our cholesterol levels?
Surprisingly foods that are high in cholesterol ( eggs ) have minimal if any effect on raising cholesterol, unless there is a specific genetic problem that doesn’t allow LDL to be broken down effectively.
How many years before our Western modern medicine begins to shift towards a more fat-tolerant and sugar-avoiding paradigm?
It has been shaping that way in recent years and the American Heart Association will be addressing some of these dietary compositional issues in the near future.
What is the dietary recommendations for an APOE4 ?
Due to the inherent increased risk of heart disease, ApoE4 affected individuals should monitor caloric intake through a relatively low carb and sat fat restrictive diet.
Is a high LDL particle count a risk factor in the context of a low carb diet with a very low CRP value?
Generally a high concentration of LDL particles (irrespective of carb concentration and/or CRP) is associated with increased risk of heart disease but there is no evidence that lowering LDL particle number beyond levels of LDL cholesterol translates into reduced risk of heart disease.
Does the cold clog your arteries?
Cold does not clog but can mildly constrict blood vessels.
Does skipping breakfast and eating fewer meals clog your arteries?
Does saturated fat or a high fat diet impair endothelial function?
Yes, at the University of Maryland we showed that high caloric, high sat fat diets directly impairs blood vessels. Check out our research results on Good Morning America .
Which of the saturated fatty acids found in common foods are the most / least beneficial for health?
Stearic acid is a neutral sat fat shown to offer some health benefit when consumed in moderation.
Is a high omega-6 : omega-3 ratio from a diet high in plants / nuts / seeds harmful in the context of a paleo diet / active lifestyle?
Other sat fats are most unhealthy when consumed in abundance.
What should those of us with familial predisposition to high cholesterol do? What kinds of things do we need to be aware of vs the typical consumer without such a predisposition?
Discuss with your physician what might be the best strategy to take based upon other associated heart disease risk factors that might be present. In “Heal Your Heart”, available in hard copy at Rodale or as an e-book at Amazon.com , we devote an entire chapter to many paleo based nutritional sources that lower cholesterol and triglycerides.
I understand that fat and cholesterol in and of itself isn’t actually bad but for some reason combined with a lot of sugar it can really destroy insulin producing cells in the pancreas. Is there a particular mechanism we’ve found and what is the dietary ratio of fat and sugar?
It is correct that our bodies produce all the cholesterol and saturated fat we will ever need and small to moderate amounts are not harmful except in unusual genetic circumstances. Likewise, moderate carb intake is not harmful when total caloric intake is not excessive. However with excessive caloric intake and/or reduced caloric expenditure, a high carb diet, as characterized by a predominance of “simple” carbs can over an excessive duration overstress the pancreas and in time produce insulin resistance. A normal ratio of fat: sugar is approximately 3:5 under normal caloric conditions.
I’m extremely interested in the concept of small dense vs big, fluffy LDL cholesterol particles. What do we know about the role they play in our health, can they indicate something about a person’s well-being other than cardiovascular risk? Is there a difference in the way that each is formed in the body? Should we be able to see the testing methods for particle type becoming more democratized in the future?
All LDL particles are unhealthy and while smaller LDL particles may be more susceptible to oxidation, there is no evidence that smaller particles are more dangerous than larger particles with respect to heart attack rates. Triglyceride levels play a major role in influencing LDL size and can predict the likelihood of whether or not you have a predominance of large fluffy or small and dense LDL particles. Testing methods are readily available but again, the clinical relevance is not established.
In his new book “ “, he provides a detailed summary of foods that can help to lower cholesterol levels naturally. You can also buy the e-book version for $6.99 on .
You can find a list of food that are good for you heart here .