First of all, it is important to understand that that "risk factor" does not mean the same thing as "cause". A risk factor is a characteristic that is associated with a diagnosis. For example, for women, being tall is associated with breast cancer. Does that mean that being tall causes breast cancer? Of course not.
It is also important to understand cholesterol is an essential component of our cell membranes, it acts as an anti-oxidant, it is a precursor for the synthesis of vitamin D as well as bile for digesting fats, and is the only source out of which our steroid hormones, such as cortisol, as well as estrogen, progesterone and testosterone which are key to reproduction, can be made. Therefore it is safe to say that without cholesterol we would not survive. Cholesterol is also the precursor to calcitrol, the steroid hormone that regulates calcium levels in our bodies by helping us absorb calcium from our food, thus playing a key role in the mineralization of our bones and teeth. Cholesterol is also manufactured in the glial cells of the brain to aid with synapses.
Cholesterol is used by our bodies to repair lesions in the arteries. Dr. Mary Enig, fat researcher, suggests that blaming cholesterol for heart disease is something like blaming firefighters for starting fires. Is it really a good idea to reduce our arteries' firefighters? The key to stopping heart disease is to stop the lesions (fires) in the arteries from occurring in the first place, by minimizing glycation by eating less sugar and high fructose corn syrup, and minimizing free radical damage by not consuming refined and therefore rancid vegetable oils AND by reducing systemic stress.
Our bodies consider cholesterol to be so essential to our survival, that every cell in our body can manufacture it as needed. If we eat little or no cholesterol, our bodies manufacture more, and if we eat a lot, our bodies don't manufacture as much. This way our cholesterol levels maintain homeostasis irrespective of our diet, and this is the reason it is so difficult to reduce or raise cholesterol levels much with diet alone.
Dr. Uffe Ravnskov, MD, PhD, who wrote the book The Cholesterol Myths, goes through study after study destroying the idea that high cholesterol levels are the cause of heart disease. In the Framingham heart study done near Boston that spanned 30 years , the researchers concluded that high cholesterol was a risk factor for heart disease, but when one really dissects the data, one must question how they came to that conclusion. For example, when the participants of the study are plotted on a graph it clearly shows that those with cholesterol levels between 182 and 222 did not survive as long as those with higher cholesterol levels of between 222 and 261. The study shows that about half the people with heart disease had low cholesterol, and half the people without heart disease had high cholesterol.
Most studies have found that for women, high cholesterol is not a risk factor for heart disease at all - in fact, the death rate for women is five times higher in those with very low cholesterol. In a Canadian study that followed 5000 healthy middle-aged men for 12 years, they found that high cholesterol was not associated with heart disease at all. And in another study done at the University Hospital in Toronto that looked at cholesterol levels in 120 men that previously had heart attacks, they found that just as many men that had second heart attacks had low cholesterol levels as those that had high. The Maoris of New Zealand die of heart attacks frequently, irrespective of their cholesterol levels. In Russia, it is low cholesterol levels that are associated with increased heart disease. The Japanese are often cited as an example of a population that eat very little cholesterol and have a very low risk of heart disease. But the Japanese that moved to the US and continued to eat the traditional Japanese diet had heart disease twice as often as those that maintained the Japanese traditions but ate the fatty American diet. This suggests that it is something else, like stress perhaps, that is causing the heart disease.
Dr. Malcolm Kendrick noticed that in the MONICA study that has been going on for about 40 years, there is no association between high cholesterol levels and heart disease. See the graph for yourself at the bottom of the article. (Dr. Kendrick wrote another interesting piece about the "disappointing results" of low fat diets in the Women's Health Initiatives heart intervention study, and the lack of association between death rates from CVD and saturated fat consumption based on the MONICA study).
These are but a small sample of the studies that contradict the idea that cholesterol is the villain in heart disease. So why has this idea held on so long? Perhaps pharmaceutical companies and the processed-food industry have a lot to gain by keeping this belief alive. Statin drugs (Lipitor, Mevacor, Zocor etc.) are mega money makers, and they definitely do lower cholesterol, but if high cholesterol does not cause heart disease, why are they necessary?
Furthermore, statin drugs may not lower overall mortality rates, as lower cholesterol levels seem to be associated with higher rates of cancer. Statin drugs work by blocking the synthesis of mevalonate, which is a vital step in the body's
synthesis of cholesterol. By blocking this step, every following step is also blocked, and this is a problem, because the synthesis of Coenzyme Q10 (ubiquinone) and squalene, both precursors to cholesterol, is also blocked. Coenzyme Q10 is very important for heart function, it acts as an antioxidant in conjunction with Vitamin E, and it is important in energy metabolism in the mitochondria of muscles, which is why muscle pain is a common side effect of statin drugs. Coenzyme Q10 is important for healthy brain function as well, and when Coenzyme Q10 levels are low, through statin use or otherwise, memory is affected. Squalene is also an antioxidant and is a potent cancer fighter. If you are on statin drugs, supplementing with Coenzyme Q10 and squalene may be very helpful.
I realize that suggesting that cholesterol levels are not associated with heart disease goes against current dogma. I am not making this suggestion in order to create controversy. After looking at the evidence, I am convinced that we are going down the wrong path. I am not alone in thinking this way - there are more and more scientists and physicians that believe that cholesterol and saturated fat stand wrongly accused. For me, the epidemiological evidence is most convincing. If we ate saturated fat and cholesterol in the form of animal fats, eggs, and full-fat dairy liberally for millennia and were heart-disease free up until the early 1900s, and just as we reduced our consumption of these foods and replaced them with sugar, vegetable oils and processed food, heart disease rates began to climb - to me it seems rather obvious that we are putting the blame on the wrong thing. Feel free not to believe this idea, but please don't simply dismiss it out of hand, either. If you have high cholesterol and you are taking, or thinking about taking cholesterol-lowering drugs, please read The Cholesterol Myths: Exposing the Fallacy that Saturated Fat and Cholesterol Cause Heart Disease so that you can make an informed decision regarding this important issue. Two other very well researched books worth reading, written by scientists but geared to the lay person are Nutrition and Physical Degeneration, by Dr. Weston A. Price, on primitive cultures, their health and their eating habits versus more modern cultures, their health and their eating habits (probably the most important book on nutrition ever written), and Mary Enig's book on lipid chemistry, Know Your Fats: The Complete Primer For Understanding the Nutrition of Fats, Oils and Cholesterol. These books are each very different from the other, but they will open your eyes to the other side of the argument, and only then will you be able to come to an informed conclusion on this issue.
Saturated fat - the misunderstood nutrient
Fats - the good, the bad and the ugly (It's not what you think!)
Food Guide Fallacy
Ravnskov, Uffe, MD, PhD The Cholesterol Myths: Exposing the Fallacy that Saturated Fat and Cholesterol Cause Heart Disease, New Trends Publishing Inc., Washington D.C., 2000.
Online at Cholesterol And The French Paradox, The Swiss Paradox, The Russian Paradox, The Lithuanian Paradox...Etc... by Malcolm Kendrick (an interesting article about the MONICA study, a long term study of cardiovascular disease, comparing cholesterol levels to CHD deaths in various countries.)
Online at How to bury $400 million by Malcolm Kendrick (an article about the "disappointing" results of the low fat Women's Health Initiative's heart intervention study, and even more interesting, a statistical analysis of deaths from CHD vs. % saturated fat consumption in various countries in Europe, based on MONICA 1998 data)
Online at Cholesterol - Friend or Foe? by Dr. Duane Graveline (an article that explains all the roles cholesterol plays in the body)
Online at The dangers of low blood cholesterol by Barry Groves
Online at bmj.com Rapid Response - Statins and Cancer: Cause for Concern by Uffe Ravnskov, MD, PhD.
Online at The Oiling of America by Dr. Mary Enig, lipids researcher (an article about how the lipid hypothesis came about)
Online at Cholesterol - A Vital Building Block of Life (a website devoted to cholesterol)
Online at The International Network of Cholesterol Skeptics (a website of researchers, scientists and medical doctors that do not believe in the lipid hypothesis)
Online at Cholesterol, longevity, intelligence and health by Ray Peat
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