Monday 10 June 2013

Measure It: Cholesterol

nutrition / trans fat panel
Courtesy of Jason Anthony at stock.xchng

In the last post for the Measure It series I looked at What are BMI and BFP?
Hope you did some testing and found out how you were going, especially for those of you in my hemisphere, going into winter it is always good to make sure you aren't losing muscle tone for excess baggage.

In today's measure it I'm going to look at Cholesterol - what it is and what the tests actually indicate.
As I've been researching for Intermittent Fasting, cholesterol, and particularly the dangers of high cholesterol, have kept coming up again and again. This is not something you should ignore. So I thought I would give you more details so you knew what was happening.


What is Cholesterol?

Very simply, it's a type of fat-like substance found in the body. It is produced by the liver and really important for your body, in the right amounts (isn't that always the way?). It does a lot of good things like build and maintain membranes, essential for the production of hormones released by the adrenal gland, helps produce bile, converts sunshine to Vitamin D, helps metabolise fat soluble vitamins including A, D, E and K, and insulates never fibres. You don't want any of that to stuff up.

You will hear talk of LDL and HDL, being two types of cholesterol. However, this actually refers to the types of lipoproteins that carry the cholesterol through your body.

LDL stands for low-density lipoproteints, often known as the 'bad' cholesterol. Having high levels of cholesterol carried by LDL leads to buildup of cholesterol in your arteries.

On the other hand, high level of HDL means cholesterol is being carried from other parts of your body back to your liver, where it can be removed for your body... which is why it's okay to have higher levels of these.


Why is High Cholesterol Bad?

So, some cholesterol is good, but too much of particularly LDL cholesterol is bad. Why?
Well, basically the higher the LDL's, the more cholesterol floating around the body, and the more likely you are to get heart disease. The cholesterol joins with fat, calcium and other substances in the blood to create plaque build up in your arteries. The result? Less blood is able to flow through the pipes, and sometimes can be blocked altogether leading to a heart attack. You get the picture.

On the other hand, having a lot of HDL means that more cholesterol is being taken out of the body, so the lower your chance  of having heart disease, which is great news. HDL appear to clean up the walls of blood vessels and removes excess cholesterol. Therefore, the higher the HDL levels, presumably the more possibly damaging cholesterol is being removed.

Therefore, you need to think of it as a ratio of HDL cholesterol over total cholesterol, rather than a number. You might have 'low' overall cholesterol, or vise versa, but if you don't have a strong ratio, you are in dangerous territory.


How Is Cholesterol Tested?

Most of the time it is measured by a simple blood test and then a lipid panel (there are now at home tests you can administer yourself if you don't like doctors, but can bring yourself to prick your own finger). It is important not to eat anything for at least 12 hours before the test, to get accurate results.

Don't like your blood being taken? Well researchers in India are developing a photographic cholesterol test, where they take a photograph of the back of your hand, and compare it to a database of images of known cholesterol levels. However, you might need to wait a while for that to hit the mainstream.

The test will look at three factors: your total cholesterol, then LDL, HDL and triglycerides (another type of lipid that circulate in your bloodstream). The results are measured in mg/dL (milligrammes/decilitre) or 5mmol/L (millimoles/litre).

It is recommended that from about the age of 20 onwards you should get testing done every five years if good, and then every year if levels are too high. (Though scary research is coming out that 1 in 10 American children may have higher than good cholesterol levels, so don't think you're safe just because you're young!)


What Do The Results Mean?

Total Cholesterol:
Refer to the following to get your total cholesterol ranges:
Less than 200 mg/dL: Desirable
200--239 mg/dL: Borderline-high risk
240 mg/dL and over: High risk

In mmol/L terms:
less than 5.2 mmol/L

LDL (bad cholesterol):
Range for LDL cholesterol:
Less than 100 mg/dL: Optimal
100 -129: Near optimal and above
130-159: Borderline high
160-189 mg/dL: High
190 and above: Very high

Or less than 3.5 mmol/L is a good target.

HDL Cholesterol:
Basically, the higher the better. For men, HDL less than 40 is considered a risk factor for cardiovascular disease.  For women, normal HDL ranges from 50 to 60 mg/dL.

or higher than 1.3 mmol/L for women and 1.0 mmol/L for men.

Triglycerides:
This is the most common type of cholesterol.  It is a type of fat which indicates the overall cholesterol ranges.  The normal range for triglycerides less than 150.  If your reading is high, your other four readings will be high as well.  Refer to these ranges for your triglycerides measurement.
Less than 150: Normal
150--199: Borderline-high
200--499: High
500: Very high

or aim for less than 1.7 mmol/L

You also have to measure your total cholesterol over your HDL.  Your TC/HDL ratio is the proportion of your total cholesterol over your HDL. The figure you get is an indicator of your risk of atherosclerosis, the process of fatty buildup in the walls of the arteries. It is recommended to maintain a ratio of below 5.  But it can differ in men and women.  The normal ratio of TC/HDL is 4.5 or below for men and 4.0 or below for women.

So, if you haven't done it recently, take the plunge and get tested. It's always better to know because there are active steps you can take to bring your ratio back into the healthy territory.

I'm going to hand it over to you guys to give any tips you have on lowering cholesterol.

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