“There are few things that humble me more than my complete and utter buffoonery when it comes to HDL lipidology…” – Peter Attia
“It’s true of all of us.” – Thomas Dayspring (Attia, 2020)
Thomas Dayspring is a nationally recognized lipidologist. That means he’s an expert on cholesterol, fat, and oil metabolism. And Peter Attia is no slouch in this area. If you’d like to spend a few hours hearing cutting-edge concepts in this area, try listening to episodes 20-24 of Attia’s podcast “THE DRIVE.”
But be warned; that video is very technical. Less than 600 people have started even one of these podcasts. We can only guess how many finished the full 5 hours. I did.
Some information wasn’t that new. For example, Attia and Dayspring mentioned that the Framingham study indicates that TG/HDL (triglycerides over HDL ratio) is 5 times more predictive of heart attack risk than LDL. They also mentioned that lipoprotein particles pass both cholesterol and fatty acids around like hot potatoes. A few of their concepts also seemed to contradict some basics mentioned later in this article.
Why would I focus this article on such simple concepts?
Because the basics of triglycerides and HDL are critical to health. But the complicated version just isn’t understandable, let alone actionable.
I did a simple version of the TG/HDL ratio in a video 3 years ago (Brewer, 2017). It was one of our popular videos (with 60,000 views right now).
Many people told me the information saved their lives. Chuck Smith is one of those people.
Chuck Smith’s story
Chuck is a business owner living in Cocoa Beach, Florida. He saw Caldwell Esselstyn for his preventive care. He lost 50 pounds on Esselstyn’s low-fat diet.
Then Chuck had a heart attack. It happened while Chuck was traveling on US Highway 1 in his Tesla at 55 mph. Chuck had nitro pills in his back seat. So he put the Tesla on autopilot, driving him to the hospital. Meanwhile, he fumbled in the back seat for some nitro tabs, which he spilled on the floor.
During his recovery, Chuck investigated how he could have a heart attack after losing 50 pounds. He found my channel. He was one of 60,000 people that watched my video on the basics of TG/HDL ratio.
He measured his own TG/HDL ratio. It was 5. It had been as high as 7. So he switched his diet from low fat to low carb.
Two years later, he lost 20 more pounds. His TG/HDL ratio is now routinely 1 or less. His heart attack risk has plummeted. His artery scan has improved. His cardiovascular (CV) inflammation panel is perfect. And he’s ready for another 50 years of healthy living.
Watch Chuck’s full story here (Brewer, 2020).
The rest of this article will ask and answer a few basic questions about the TG/HDL ratio.
What is triglyceride?
Triglycerides (TG) are fats. Each triglyceride molecule contains 3 fatty acid molecules held together by a glycerol molecule. Fatty acids are fats, while a glycerol is a carbohydrate. The image below of triglyceride components is from Chemistry Libre Texts.
What are good blood levels of TG?
Target TG levels between 100 and 200 mg/dL (or about 1 to 2 mmol/L) are usually considered borderline. Lower levels are optimal. Some disease states feature TG levels over 500 mg/dL or 5.7 mmol/L.
Why is there TG in the blood?
The most common reason for elevated triglycerides is prediabetes. Chronically high insulin stimulates adipokines and hormone-sensitive lipase. This results in the release of too many fatty acids from fat cells. These excess fatty acids take up space in HDL and LDL particles.
TG can also become elevated in several inherited diseases.
What is HDL?
HDL is an acronym for high-density lipoprotein. HDL particles are considered being responsible for bringing cholesterol from the body to be metabolized by the liver. (That’s opposed to LDL or low-density lipoprotein which brings cholesterol to different parts of the body.)
This is an image of HDL from Biosciencenotes.com.
Will an improvement in HDL lead to better health?
Yes. Improvement of HDL function improves arterial health (Chiesa 2019). How? By:
- Improving nitric oxide;
- Decreasing oxidase enzyme function;
- Decreasing adhesion molecules;
- Decreasing monocyte infiltration; and
- (Possibly) improving reverse cholesterol transport.
What is remnant cholesterol?
We’ve talked about TG, HDL, and a bit about LDL. There’s another thing we ought to cover—remnant cholesterol.
Remnant cholesterol (RC) is the most dangerous type of cholesterol particle. It’s also called triglyceride-rich lipoproteins (TGRLs), which consists primarily of VLDL (very low density lipoproteins) and IDL (intermediate density lipoproteins) (Dhindsa, 2019).
Remnant cholesterol is short-lived in the plasma of a healthy person. RC particles appear only briefly after a meal. They are then metabolized into other lipoproteins by the breakdown of triglycerides inside an RC particle. This breakdown is accomplished by lipoprotein lipase lining the luminal surface of capillaries.
RC is also higher in the serum of those with CV disease risk (around 15 mg/dL and above). It is calculated by subtracting LDL and HDL from total cholesterol (Feldman, 2020).
Do high TG levels affect HDL and LDL levels?
The image below shows how LDLs and HDLs transport TG. It is from the National Lipid Association’s website, used with permission from Tom Dayspring (Lillo, 2020).
Here, an enzyme called CETP (cholesteryl ester transfer protein) facilitates the exchange of cholesterol in large HDL and large LDL with TG. What CETP does is it takes cholesterol out of large HDL and LDL particles and then transfers TG into these particles. In turn, hepatic (liver) lipase metabolizes TG-rich HDLs and LDLs, leading to smaller HDLs and LDLs.
In a nutshell, high TG levels affect HDLs and LDLs. And prediabetes leads to high TG levels.
Look at the image below showing what a lipid profile would look like in a patient with prediabetes.
- The patient has elevated TG levels (216 mg/dL), a low HDL level (34 mg/dL), and a high LDL level (139 mg/dL).
- There was a decrease in the size of HDLs. Normally, the HDL curve should be a smooth bell curve peaking where the red circle is drawn. Here, the large HDLs are taken out.
- There was also a decrease in the size of LDLs. Though the LDL has a good bell curve at the right, the curve’s peak shifted to the left. This means there are more smaller and denser LDLs. (We call this a B pattern LDL distribution.)
Aside from prediabetes, this patient actually has another problem—familial hypercholesterolemia (FH). Neither condition was noticed before the patient came to us.
To make matters worse, the patient also has an elevated TG/HDL ratio—216/34 or 6.4! I recommend a goal of 1.5 or less.
What is the TG/HDL ratio?
TG/HDL ratio is the triglyceride-to-HDL ratio. To find your TG/HDL ratio, simply put your blood triglyceride value over your blood HDL level, as measured by your medical laboratory blood test.
Why is TG/HDL ratio important?
TG/HDL ratio is important because it is an important predictor of CV disease risk. It is also a marker of insulin resistance, and insulin resistance is the major cause of prediabetes, metabolic syndrome, and type 2 diabetes. (Cordero, 2009)
The Women’s Ischemia Syndrome Evaluation (WISE) study studied 544 women referred for CV disease evaluation (Bittner, 2009). The TG/HDL ratio ranged from 0.3 to 18.4. It was a powerful predictor of all mortality and cardiovascular events.
This chart shows the WISE study range of TG/HDL. Individuals with lower TG/HDL ratio had lower CV disease risk.
What is a good TG/HDL ratio?
Lower TG/HDL ratios are better. In the discussion of science, studies, and treatment, there has been a tendency to go with higher ratios to show the largest impact on CV disease risk and death.
Here are the typical cut points for risk (Sigurdsson, 2014):
- In US (mg/dL) – less than 2 is ideal; above 4 is too high
- In Europe (mmol/L) – less than 0.87 is ideal; above 1.74 is too high
Does ethnicity matter in terms of TG/HDL ratio?
The TG/HDL ratio appears to vary by ethnicity. TG/HDL ratios are higher in Hispanic Americans (3.9) than non-Hispanic whites (3.3) and non-Hispanic Blacks (2.9) (Willey, 2011).
Thus, many say that we should go target different levels based upon ethnicity. Those same scientists have said that a TG/HDL of 2.0 is diagnostic of prediabetes for African-Americans.
Although the patterns of TG/HDL ratio vary by ethnicity, I do not recommend focusing on this. There are several reasons, such as the fact that ethnicities are often mixed and unknown.
But the biggest reason is that TG/HDL ratio is an indicator of the health of insulin and glucose metabolism—the lower the ratio, the better the patient’s health. Not to mention that most of the cut points used in research as markers for prediabetes are too high. For example, ratios of 2 and 3 confer risk, no matter what your ethnicity is.
A TG/HDL ratio of 3 confers a higher risk, so all of us should focus on this important number. No matter which ethnicity, the goal should be as low as possible. Like I mentioned in the previous section, I do recommend that my patients target 1.5 or less.
How can you naturally lower TG and raise HDL?
The most effective ways to improve your TG/HDL ratio (that is, lower TG and raise HDL cholesterol) are:
- Lose weight. Body fat used to be considered as an inert energy storage tissue. Now we know it is an endocrine tissue that releases chemicals (like adipokines) that cause insulin resistance, prediabetes, and CV risk (Kwon, 2013; Rabe 2008).
- Eat fewer carbs. Get into a lower carbohydrate diet (Dashti, 2004).
- Exercise. Exercise raises HDL and lowers TG (Sopko, 1985; WebMD, “Will Exercise Really Lower Triglycerides?”).
- Take niacin. It is one of the few supplements that lowers TG (down by 20-50%), raises HDL (up by 15-35%), and lowers LDL (down by 10-25%) (Simon, 2007; Kamanna, 2008).
- Get dietary and supplemental omega-3s (Yanai, 2018).
Which medications improve TG/HDL ratio?
- Statins. The major impact of statins on TG/HDL ratio is to lower TG. But usually, statins are given to lower LDL. Sometimes they can also lower HDL, but still not as much as how they lower TG. They can lower TG by as much as 50% (Maki, 2012).
- Fibrates (Lopid, Fibricor, and Tricor);
- Prescription-strength niacin (Niaspan);
- Prescription-strength omega-3s. Icosapent ethyl (Vascepa), Epanova, and Lovaza are prescription forms of omega-3s (Bhatt, 2019; WebMD, “What medicine is used to treat triglycerides?”)
Can lowering carbs actually improve TG/HDL, RC, and CV risk?
Yes. There is plenty of evidence showing this. Multiple studies range from clinical trials in animals and humans to meta-analyses. Here are 4 of them:
- The Abbasi study was a human clinical trial using a crossover design. People ate high carbs (60% of calories) for 2 weeks, then low carbs (40% of calories) for 2 weeks, with a “washout period” of 2 weeks in between. The high-carb diet doubled TG levels, tripled remnant cholesterol, and lowered HDL by 15% (Abbasi, 2004).
- The Wang study is a randomized clinical trial in laboratory mice (Wang, 2008).
- The Volek study is a meta-analysis. It reviews pre-2005 studies which had already shown that low-carb diets decrease triglycerides and remnant cholesterol while increasing HDL (Volek, 2005).
- The Ebbeling study was also a human subjects clinical trial. It was done at Harvard. Subjects on a low-carb diet had lower TG and higher HDL. Also, researchers showed that low-carb diets were less likely to result in weight rebound due to improved energy expenditure and leptin (Ebbelin, 2012).
My name is Ford Brewer. I’m a co-founder of PrevMed. We do heart attack, stroke, cancer & disability prevention. I’m licensed in over 40 states. We travel to states to see patients, and we provide telemedicine. Here at PrevMed, we can’t make you do high-Intensity intervals and resistance training or manage an appropriate BMI. But we can help you by telling you what you need to do, why, and how to organize around it, and provide recommendations to support you in staying healthy. If you’re interested in how we can help you, check out our services page.
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