The Truth About Cholesterol: The Basics
There is so much misinformation and outdated science on cholesterol that a lot of people live in - needless - abject terror of certain foods. In this article, I hope to set the record straight so that you can apply a more informed (and effective) approach to your cardiovascular health.
Cholesterol and its link to heart disease is, undoubtedly, a hot topic. It is better understood than it has been in the past but not everyone - or every doctor, for that matter - has kept up-to-date with the most recent findings. Doctors have, of course, had years of intensive training and have a genuine desire to help their patients. In their defence, there simply are not enough hours in the day to re-educate themselves (and their patients) on such a rapidly evolving topic. For this reason, the following may completely contradict what you currently believe to be true:
Blood cholesterol simply does not exist. Cholesterol is not systematically dumped into the bloodstream. Rather, it is transported through the blood (along with triglycerides) in substances called lipoproteins (molecules containing both fat and protein). This point may well come across as nit-picking but it will, hopefully, become clearer in a minute.
Cholesterol alone does not determine the risk of heart disease. The confusion seems to stem from oversimplification of the very complex symphony of events that has to occur for the development of heart disease. Not everyone with high cholesterol develops heart disease and not everyone with normal cholesterol avoids it. While it is true that there is an association between cholesterol and heart disease, it is not the root cause. The concentration or number of lipoproteins carrying cholesterol through the blood (lipoprotein particle number or LDL-P) is a more accurate predictor of heart disease. In addition, the cholesterol content of LDL particles varies more than two-fold among individuals. One person may have large, more cholesterol-rich low-density lipoproteins (LDL) while a second may have smaller cholesterol-poor LDL particles. A person with the same concentration of low-density lipoprotein cholesterol (LDL-C) as another may have higher numbers of LDL particles. This discordance in certain individuals also makes LDL-P a more accurate predictor of heart disease. Imagine a busy road (blood vessel), if you will. Traffic is caused by the number of vehicles (lipoproteins) on the road not the number of people (cholesterol) in each vehicle. In recent years, considerable doubt has been cast on the rationale of using cholesterol as a predicting factor in the development of heart disease. Taking total cholesterol into account along with triglycerides, low-density lipoprotein (LDL) (and the presence of oxidised LDL), high-density lipoprotein (HDL), and lipoprotein particle number is much more indicative of risk. I will address the factors affecting lipoprotein particle number (LDL-P) in a subsequent article.
Lower cholesterol is not better - particularly for women and the elderly. Moderately elevated cholesterol (by current standards) in women may prove to be not only harmless but beneficial according to a Norwegian study. It found that cholesterol levels were inversely proportional to all-cause mortality and cardiovascular disease mortality. In his exciting new book - The End Of Alzheimer's - Dr. Dale Bredesen makes the link between low cholesterol levels and cognitive decline. He discovered that the likelihood of brain atrophy (or shrinkage) was higher in patients with total cholesterol levels of less than 3.8mmol/l.
Eating cholesterol-rich foods does not elevate cholesterol - in most people. In fact, we get a lot less cholesterol from food than you may think. Of the 25% obtained from the diet, only a small amount can be absorbed by the body. The liver's production of cholesterol accounts for a whopping 75% of all cholesterol found in the body. Our bodies maintain this percentage by dutifully making more when dietary cholesterol is restricted and vice versa. 1 in 4 people have increased cholesterol levels after eating foods that contain cholesterol but, as I said earlier, this is not indicative of the risk of heart disease.
Cholesterol is absolutely essential to life. Once this is fully understood, one can no longer label it as "good" or "bad". It is responsible for the formation of cell membranes surrounding each and every cell in the body and therefore influences cell to cell communication and transport of substances into and out of each cell. If our cells had no membranes, they would cease to exist - and, very shortly afterwards, so would we. Cholesterol is also a precursor for all hormones, without which all processes in the body would effectively grind to a screeching halt. The brain is especially rich in cholesterol because it supports learning and memory. It is, therefore extremely unwise to go to great lengths to lower such a key player in the maintenance of our overall health - particularly without first determining the root cause.
Elevated cholesterol is not a disease in itself but rather a symptom of something deeper going awry. I like to think of symptoms as invitations to look for root causes which would then dictate one's approach. I would encourage you to do the same.