Do Low Cholesterol Levels Cause Cancer?
I thought it was important for me to construct a public reply to a recent medical study that reported both high cholesterol and low cholesterol were associated with higher cancer rates because too many people are still confused about this, including the scientific research community. This is because so few people have performed a comprehensive, in-depth review of the scientific research on nutrition and cancer, so they base their decisions on a narrow and incorrect interpretation of the literature. This recent article and the comments by the media and even by physicians and scientists illustrate pervasive ignorance and confusion about human nutrition.
The study in question was published in the August 26th issue of the Canadian Medical Association Journal (CMAJ).1 It showed that people whose LDL cholesterol was below 2.8 mmol/L (109) had a higher risk of certain cancers (primarily lymphatic and blood cancers) and people whose LDL cholesterol was above 3.9 mmol/L (152) had a higher risk of certain cancers (primarily breast and digestive tract) as well.
My book, Cholesterol Protection For Life, covered this issue in more depth. In it, I explained that certain illnesses, especially cancer, lower cholesterol levels by decreasing the liver’s ability to produce cholesterol and that having a low cholesterol in spite of an unhealthy (high) cholesterol-promoting diet could be an early sign of an undiagnosed cancer. The types of cancers that have been reported to cause low cholesterol levels include lung, liver, lymphatic and hematopoietic cancer, the same cancers associated with low cholesterol in this study.2
My book, Disease-Proof Your Child, reviews the science and explains that cancer is predominantly caused many, many years before it first appears (over 40 years) and that cancerous cells are present in the body for over 10 years prior to diagnosis, when the clump of cancerous cells eventually become large enough to be viewed by the human eye or when the first signs or symptoms appear. This study only followed people for less than 5 years. They recorded the cancers that occurred in the last 2½ years of the study.
The findings were not surprising, but consistent with the main body of literature on this subject. We would expect people who are eating a diet that promotes high cholesterol would have higher cancer rates, because the same diet-style that promotes high cholesterol and heart disease also promotes cancer. We would also expect to find that very low cholesterol was also associated with more cancers occurring because some people in the cohort would have undiagnosed (occult, early stage) cancer that would eventually become diagnosed in the last 2½ years of the study. Their low cholesterol was a sign of early (undiagnosed) cancer, not a cause of their cancer. These people have low cholesterol in spite of not earning low cholesterol with nutritional excellence. Their cancer caused the low cholesterol, not the other way around.
What I stated in Cholesterol Protection For Life is that a low cholesterol that is earned through adherence to a diet rich in vegetables, beans, seeds, nuts and other health-promoting foods will protect you against heart attacks and cancers, however if you have a very low cholesterol that you did not earn via healthy living and a healthy diet, it might be a sign that a disease is present that lowers cholesterol, such as cancer.
To conclude, don’t be alarmed if your cholesterol is low, if you have earned it. Low cholesterol earned through high vegetable consumption and a micronutrient rich diet is linked to protection against all cancers, and populations eating a vegetable-centered-diet earn low cholesterol levels and have dramatically lower rates of cancers along with lower heart disease rates.3 This does not have to be such a confusing subject. Its simple, the prescription is nutrition for improved health and a longer life!
1. Yang X, WingYee S,Ko GT. Independent associations between low-density lipoprotein cholesterol and cancer among patients with type 2 diabetes mellitus. CMAJ 2008;179(5):427-437.
2. Abbott C, Meadows AB, Lier K. Low cholesterol and non-cardiovascular mortality. Mil Med 2000;165(6):466-9.
3. Campbell TC. Parpia B. Chen J. Diet, Lifestyle and the etiology of coronary artery disease: The Cornell China Study; Am J Cardiol. 1998. 82(10B): 18T-21T.