About the killer called cholesterol, and why it ain’t so.
Part 1 of 2 by Chris Bellanger from Prahran health Foods
Nutritionist, Holistic Personal Trainer, BHSc (Naturopathy) Student
The much maligned waxy lipid known as cholesterol is technically a steroid-alcohol, and is found in every cell’s membrane (like the cells skin) and in our blood plasma. It’s essential for insulating neurons, building and maintaining cellular membranes, metabolizing fat soluble vitamins, producing bile, and kick-starting the body’s synthesis of many hormones, such as testosterone, estrogen, and even vitamin D.
Given the obvious importance of this molecule to our overall health, you might think our bodies would evolve to synthesize enough of this substance to guarantee a reliable supply… and you would be correct. Our livers produce around 1,000-1,400 mg of cholesterol daily, so therefore restricting dietary intake to <300 mg as we are advised by the ‘experts’ would seem to make little difference, especially since neuro-feedback to our liver simply tells it to produce more, if it is in short supply. Similarly, when volunteers consume 2-4 eggs daily in feeding studies, there is little to no impact on blood cholesterol.
The terms cholesterol and saturated fats have become synonymous with cardiovascular disease, arterial plaque and heart attacks to such an extent that most people still believe eggs and butter are an express train to an early grave, despite the nutrient density of these historically important foods in many cultures.
However, when reviewing the last 50 years of data with no agenda, such as one might have if funded by powerful vegetable oil or pharmaceutical drug lobbies, it becomes clear that there is no such link.
Instead of boring you with the voluminous amount of research refuting the cholesterol theory, let me first ask you a few common sense questions?
- How can we possibly base human nutritional recommendations on animal studies such as the original cholesterol theory which came about by feeding normally herbivorous rabbits a high cholesterol diet?
- Why do the French, Spanish & Russians all consume high cholesterol diets and have low incidence of cardiovascular disease (CVD)?
- Why do so few people on statins (cholesterol lowering medications) have less CVD, yet more muscle pain and damage, diabetes and memory impairment?
- If dietary cholesterol accounts for less than 25% of blood cholesterol, and your body produces more in the absence of dietary cholesterol, then how can lowering dietary cholesterol make a difference?
- If saturated fats are so bad for us, why have heart disease and atherosclerosis reared their heads primarily since the industrial age when we have reduced saturated fat intake, and increased sugar and vegetable oils?
And speaking of low -fat, high- carb diets, why do you suppose Sylvan Lee Weinberg, former president of the American College of Cardiology said :
“The low-fat, high -carbohydrate diet …may well have played an unintended role in the current epidemics of obesity, lipid abnormalities, type 2 diabetes, and metabolic syndromes. This diet can no longer be defended by appeal to the authority of prestigious medical organisations?” (1)
Could it perhaps have something to do with 29 billion dollars in annual sales from statin drugs? According to Dr David Newman, “virtually all of the major statin studies were paid for and conducted by their respective pharmaceutical company. A long history of misrepresentation of data and occasionally fraudulent reporting of data suggests that these results are often much more optimistic than subsequent data produced by researchers and parties that do not have a financial stake in the results.” (2)
Consider that total fat content of traditional diets varied from 30% to 80%, but only about 4% came from polyunsaturated fats derived from grains, nuts and seeds. These oils tend to be high in omega 6 fats and contribute to inflammation and oxidative damage, especially when paired with high carbohydrates, which has a greater affinity for artery damage, thus leading to cardiovascular disease.
Interestingly, normal levels of cholesterol in traditional cultures were 200+ and more as we aged BUT inflammation was lower due to higher overall antioxidant levels and omega 3’s.
Many people have cholesterol in the ‘ideal’ 100 range and yet still have heart attacks due to high inflammation and triglycerides from high carbohydrate diets, while just as many have much higher levels, yet with lower inflammatory markers, arterial plaque, triglycerides and adiposity, and thus they are at a much lower risk.
Meanwhile, studies on low carbohydrate diets (which typically are higher in saturated fats, and thus cholesterol) not only do not tend to raise blood cholesterol, but also have beneficial effects on cardiovascular disease such as reduced body weight, reduced triglycerides, lowered fasting glucose, normalised blood pressure, reduced abdominal circumference, plasma insulin and c-reactive protein, and increased HDL cholesterol (3)
Even in the 25% of hyper-responders (that fraction of the population that either produce or absorb more cholesterol than the majority), dietary cholesterol moderately increases BOTH LDL (“bad cholesterol”) and HDH (“good cholesterol”), thus still having no impact on heart disease risk (4)
Much research is available, with varying methodologies and outcomes For example, a recent systematic review collating data from 72 studies and involving more than 600, 000 participants showed no association with saturated fats and heart disease, while trans-fats were strongly associated with increased risk of heart disease. (5)
Trans-fats are primarily found in margarine and other polyunsaturated (vegetable) oils which have been ultra-heated.
If you are wondering about saturated fats and stroke, a Japanese prospective study following 58, 000 men for 14 years found an inverse association, meaning the more saturated fat consumed, the lower the risk of stroke. (6)
It is important to keep in mind, though, that response to dietary cholesterol will average out with a certain percentage of the population being higher and others being lower responders.
Cholesterol is like the body’s fire fighter… it’s present at the scene of the fire like the immune system is present at the scene of injury, BUT IT IS NOT THE CAUSE of the injury. Cholesterol is a healing agent, and so this is why cholesterol goes up after serious burns, for example, to support wound healing.
Cholesterol can also increase in times of extreme stress such as athletic training, due to chronic lack of sleep, during infection (LDL is antimicrobial), in response to hypothyroidism, during times of weight loss or ketosis.
So what does reducing cholesterol via medication do to our health? Well how about reducing mitochondrial function (energy production), causing muscle weakness, joint pain, fatigue, and possibly contributing to memory impairment. (7)
In a clinical setting, it has been found that measuring blood LDL cholesterol in fact tells us very little about the potential for CVD with increasing numbers of doctors and naturopaths today monitoring more evidence based markers for CVD which include C-reactive protein (ideally under 2), high density lipoprotein (HDL), triglycerides, plaque deposition (ideally under 100), blood pressure and central adiposity or weight gain around the abdomen.
In conclusion, there is evidence based research and years of nutritional tradition to substantiate the beneficial role of cholesterol in maintaining optimal health status , including cardiovascular health.
In part two of this article, we will explore in greater detail the pro’s and con’s of the controversial cholesterol lowering drugs, and natural and perhaps safer methods of reducing CVD risk.
- Chowdhury R, Warnakula S, Kunutsor S, et al. Association of Dietary, Circulating, and Supplement Fatty Acids With Coronary Risk: A Systematic Review and Meta-analysis. Annals of Internal Medicine. Published online March 18 2014