Sunday, April 12, 2015

Cholesterol: Part Two "If Cholesterol is not the Enemy, What is?"


Like you I’m trying to find out more about healthful living without being fanatical.  I’m not a medical professional, but I have do have a science background in my training and have had a long-standing interest in nutrition and health.

There’s some challenging research work being done here in New Zealand (and overseas) that indicates “it is likely that the low-fat diet approaches and lipid hypothesis perpetuated over the last several decades may have caused more harm than good.”1 AUT video clip 2  
 
Is it true that we should be feeding ourselves and our families with a low-fat diet to prevent us from having high cholesterol and consequent heart disease in the long term?

I’m drawing from this research and from my own review of the book The Great Cholesterol Myth
3 authored by nutritionist J. Bowden Ph.D and cardiologist S. Sinatra M.D (published in 2012 and available in your library or at Book Depository).  This book is worth reading if you are concerned about heart disease or diabetes.  It is well laid out and I found it reasonably simple to read.4

If you’ve ever had a blood test for cholesterol5 in NZ or Australia you will probably have been told that the LDL (Low Density Lipoprotein) is the baddie and HDL (High Density Lipoprotein) is the goodie. If the test showed you had more than 2.0 millimoles per litre of LDL in your blood a low-fat diet would have been recommended to you in order to reduce the bad cholesterol.

You may remember from last week’s article that it’s not actually the cholesterol that’s the problem it’s the “boat.”  Think of cholesterol as the cargo that’s carried along on protein “boats” called HDL or LDL.  Based on more recent research the concept of LDL = bad and HDL = good is outdated. More about why the boat can cause a problem in a moment.

Okay, back to the question we all want the answer for:

If cholesterol doesn’t cause heart disease what does?
Answer: Inflammation

There are two types of inflammation we experience in our bodies. 

1. We’re all familiar with inflammation that occurs when we get a cut on our skin.  This is called acute inflammation and it hurts. Immune cells rush to mend the injured area.

2. Chronic inflammation within the body can lie undetected, as pain is not evident. It is characteristic of many diseases like arthritis, cancer, kidney and liver disease and cardiovascular disease.

So what is the enemy and how does chronic inflammation happen?

1. Chronic inflammation is begun by damage done to LDL “boats” by free radicals - the enemy! This damage is called oxidation. Think of the browning that happens to a cut apple sitting on your plate for a while. That’s oxidation happening.

2. Damaged (oxidised) LDL “boats” carrying cholesterol can stick to the lining of the artery wall. This delicate and sensitive, innermost layer of the wall of our arteries is called the endothelium and is only one cell thick.

3. This attaching of the oxidised, cholesterol-carrying LDL boat triggers the immune system into action and ultimately causes inflammation that begins the process of atherosclerosis in the thin wall of the artery.

It’s not the cholesterol; it’s the damage done to the “boat” that’s the problem!
Let’s stick with the picture of the boats carrying the cargo.  LDL (Low Density Lipoprotein) “boats” deliver cholesterol to the cells that need it for things like production of hormones, brain cells, for fighting infection…and so on.  The HDL (High Density Lipoprotein) “boats” remove the excess cholesterol if it’s not needed.

If the LDL boat and its cargo become oxidised and then attached to the endothelium the process of inflammation begins as cells from the immune system arrive to take care of the invader.  Plaque will then form at the damaged site. This pocket of plaque can in time rupture causing blood clots which can block the flow of blood to the heart resulting in a heart attack.

Not all LDL “boats” can turn bad when damaged through oxidation.  New technology has identified several types of LDL, for example LDL pattern A and LDL pattern B.

LDL pattern A is large and fluffy in structure compared with LDL pattern B which is dense, hard and is most likely to be damaged by oxidation. We all have both these types of LDL in our bodies, but some people seem to have higher levels of one or the other.  Both types are good, but pattern B is easily oxidised by free radicals and then becomes a problem.

There is advanced blood testing available today that can measure these new particles which are a better indicator of potential heart disease than our current tests.  However this is not yet available in NZ; you would need to ask your doctor to send a sample of blood offshore for this advanced testing.6

It would be useful to know some healthful practices that would minimise free radicals and prevent oxidation of these LDL cholesterols and consequent inflammation of our artery inner walls wouldn’t it?

What can we do about minimising the damage done by free radicals?
We can eat more foods high in antioxidants that deal to the free radicals in our bodies, for example fresh fruit & veges, whole foods, raw cacao, etc…  (more to come about this in a subsequent newsletter/blog).  We need to avoid consumption of substances that create free radicals - stop smoking, check our intake of heavy metals, be aware of insecticides, toxins in the air, additives in the food supply and highly processed foods, all of which all contribute to oxidation damage in our bodies.

Let’s take care of our overall health - minimise and manage stress, exercise, be grateful, be compassionate, work to be happy (as they say “a cheerful heart is a good medicine”), and make time to enjoy our friends and family more.

BUT… oxidation caused by free radicals is only one of the conditions that cause inflammation, another is … sugar!  It appears that “this food is a far greater danger to our overall health than fat ever was.”7

Bibliography
1. http://www.aut.ac.nz/profiles/grant-schofield I first started becoming interested in this topic when I read a research article about high fat/low carb sports nutrition published by AUT (Auckland University of Technology) last year under the supervision of Dr. Grant Schofield, Professor of Public Health, and Director of the Human Potential Centre at AUT.
2. Fast Fwd this video clip about 5 minutes to lose the intro and the talk about the restrooms etc!  http://www.humanpotentialcentre.aut.ac.nz/
3. Where to buy
The Great Cholesterol Myth http://www.bookdepository.com/Great-Cholesterol-Myth-PhD-Jonny-Bowden/9781592335213
4. Comments on the Framingham Heart Study 1948-1964, on which many of the public health guidelines about cholesterol have been made: https://thescienceofnutrition.files.wordpress.com/2014/08/concerning-the-possibility-of-a-nut.pdf
5. Blood testing in NZ https://www.southerncross.co.nz/AboutTheGroup/HealthResources/MedicalLibrary/tabid/178/vw/1/ItemID/156/High-blood-cholesterol-levels.aspx#types
6. NMR test, the Lipoprotein Particle Profile Test (LLP), the Vertical Auto Profile Test (VAT), are some of the advanced blood tests available, but not in NZ currently.
This site makes mention of the various blood tests done in NZ.  http://www.bpac.org.nz/resources/campaign/cardiovascular/lab_cardio.asp?page=14
Dr Bill Reeder: Advanced blood testing & where to get it done http://www.medcom.co.nz/?page_id=188
7. J. Bowden Ph.D and S. Sinatra M.D,
The Great Cholesterol Myth: Why lowering your cholesterol won’t prevent heart disease – and a statin free plan that will.  Fair Winds Press, MA, USA. p 54.

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