Does high total cholesterol (TC) = high cholesterol?
No. Continue reading to understand what a lipogram is, and about good and bad cholesterol.
How to calculate total cholesterol
“There is a drive to measure total cholesterol, but it is useless in isolation.”
You want to know how to calculate total cholesterol, but why?
Is it at all important?
Total cholesterol = LDL + HDL + 20% triglycerides.
To calculate it, you need to know more about the components found in lipograms.
Does high total cholesterol (TC) = high cholesterol?
No, ‘high cholesterol’ does not necessarily refer to your total cholesterol (TC); most people are unaware of this.
“You could have a high TC and not be at risk. The opposite is also possible; a normal TC doesn’t mean you are not at risk.”
It is the bad cholesterol found in LDL that you should fear.
Let me use my partner J and my TC values to illustrate this. Yes, he has consented!
It looks worse for me when comparing our S-cholesterol (Serum Cholesterol/TC) counts, don’t you think? However, this is not the case.
“I am low risk, and J is at high risk.”
If this confuses you and you would like to know more about:
- calculating your risk, and
- knowing your treatment goal.
Also read: My blog tutorial, Cholesterol Goal Guidelines, explains it using three case studies.
Units of measurement
In South Africa, the unit of cholesterol we work with is mmol/L; some countries use mg/dL. Use this cholesterol units converter if mmol/L is unfamiliar to you.
Why do we test TC if it doesn’t reflect risk?
You need TC to calculate the Chol:HDL ratio.
Back to basics.
I will build your understanding one step at a time so that you know why and how to lower your cholesterol.
Image by Gerd Altman from Pixabay
Why must we treat high cholesterol?
High cholesterol is an independent risk factor for blood vessel disease.
Also read: How to lower my cholesterol
Over time, it might cause heart attacks, strokes, kidney disease, and even erectile dysfunction.
Some doctors believe this is false, that cholesterol is not the problem; Inflammation is.
“I have seen young patients with only high cholesterol as a risk factor have heart attacks and strokes, and die in one tragic incident.
None of these patients had high blood pressure or diabetes.
They did not smoke and were physically active.”
I agree that inflammation is a strong contributing factor, intensifying the vascular damage done by cholesterol.
Also read: My article on how to decrease systemic inflammation with diet
Dr Michael Greger, the author of How Not To Die, summarises my beliefs in this video.
What is cholesterol?
Cholesterol is a fatty or waxy substance found in the body. Believe it or not, we need cholesterol for our bodies to function.
It is a crucial building block for:
- cell walls, especially in the brain and nerves,
- bile, which helps us absorb vitamins, and
- hormones, for example, testosterone, estrogen, and cortisol.
We make most of our own cholesterol and absorb only about 20% of it from our diets.1
You’ve heard the phrase; too much of a good thing is bad for you; this also applies to this essential substance.
What are the forms or types of cholesterol?
Cholesterol and other fats are transported in the bloodstream between organs in the form of lipoproteins.
These lipoprotein molecules are a mixture of fat (lipo, meaning lipid) and water-soluble proteins.
This is necessary because blood is water-based. You know oil doesn’t mix with water!
LDL (Low-Density Lipoprotein)
This is the enemy: meet bad cholesterol.
This lipoprotein moves cholesterol from the liver to the body‘s tissues. It contains more than 50% cholesterol and approximately 10% triglycerides.2
Excess cholesterol forms plaques in arteries, causing narrowing and organ disease. High LDL means an increased risk for blood vessel disease and organ damage.
HDL (High-Density Lipoprotein)
This lipoprotein moves cholesterol from the organs to the liver. The liver breaks down cholesterol and excretes it into the intestine as bile salts. It contains about 25% cholesterol and less than 5% triglycerides.2
The higher the HDL, the more cholesterol is removed.
Therefore, HDL is known as good cholesterol.
Triglycerides, found in both these lipoproteins, are energy-storge fats.
Glucose that is not burned up immediately to create energy is converted to triglycerides.
VLDL (Very-Low-Density-Lipoprotein)
This precursor to LDL transports triglycerides from the liver to the fat cells. VLDL contains 50 to 70% triglycerides.2,3,4
After the VLDL delivers the triglycerides, it is converted into LDL.1,2
Triglycerides
All lipoproteins carry these fats, but the main transporter is VLDL.
Triglycerides are formed by excess glucose, the body’s energy source, that has not been used.
Sugars, carbohydrates, and alcohol are broken down into glucose.
What is a lipogram?
Also known as a lipid (fat) profile. A lipogram is a blood test that lists different fat types and their calculated ratios.
These ratios help with vascular risk prediction.
Your full lipogram lists:
- Total Cholesterol,
- LDL,
- HDL,
- and triglyceride levels.
As mentioned at the beginning of this post, Total cholesterol = LDL + HDL + 20% triglycerides.
Must a cholesterol test be done fasting?
Yes, always have your cholesterol blood sample after fasting.
This is important because:
- It ensures a comparable result every time you repeat the test.
- Cholesterol reference ranges are based on fasting results.
“I recommend requesting a full lipogram for the first time you check your cholesterol to accurately assess your risk and calculate LDL goal”
Read my blog tutorial on interpreting lipograms to know how we calculate your goal. This helps in calculating risk and LDL goals.
What does fasting mean?
For at least 10 hours before the test. You should rest, have nothing to eat, and only water to drink.
Fasting overnight is the easiest way of controlling these variables.
Do not eat from 22h00 the night before you have the blood drawn.
Then, get to the laboratory at 08h00 on the morning of the test.
Do I have to do a full lipogram?
Ideally, you should request a full lipogram for the first time you check your cholesterol.
This will help you accurately assess your risk and help you work out your LDL goal.
” You only need an LDL for follow-ups if a full lipogram is too expensive each time.”
What if I can’t afford a full baseline lipogram?
“Are you cash-strapped but still want some idea of your possible risk?
I recommend an LDL over a TC.”
My article on cholesterol goal guidelines shows that knowing only your total cholesterol is pointless.
An LDL is better than nothing.
References
- How it’s made: Cholesterol production in your body. Harvard Health. (2017, February 6). https://www.health.harvard.edu/heart-health/how-its-made-cholesterol-production-in-your-body
- The Merck Manual of Medical Information – Second Home Edition 2003
- Lopez-Jimenez, F. (2022, June 17). VLDL cholesterol: Is it harmful?. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/expert-answers/vldl-cholesterol/faq
- Sherrel, Z. (2021, March 4). VLDL and LDL: What’s the difference, causes, treatments. Medical News Today. https://www.medicalnewstoday.com/articles/vldl-vs-ldl
