Non-HDL cholesterol is all the “bad” cholesterol in the body that isn’t carried by HDL particles that carry the “good” cholesterol. Essentially, it is all the cholesterol that can cause hardening of the arteries and build-up of plaques. Research shows that it is one of the best markers for assessing the risk of heart disease, heart attack, and stroke. Read more to discover what increases non-HDL cholesterol and what you can do to reduce it and your risk of heart disease.
What is Non-HDL Cholesterol?
Lipoproteins are molecules that carry cholesterol and triglycerides (fats) around the body. Since cholesterol and triglycerides do not easily dissolve in the blood, lipoproteins help transport them around [1].
You can think of lipoproteins as cars on a highway (blood vessels) and cholesterol and triglycerides as the passengers.
The four main types of lipoproteins are:
- High-density lipoprotein (HDL): carriers of so-called “good cholesterol”
- Low-density lipoprotein (LDL): carriers of so-called “bad cholesterol”
- Very low-density lipoprotein (VLDL): carriers of some cholesterol and mostly triglycerides; VLDL eventually becomes LDL
- Intermediate-density lipoprotein (IDL): the transition form between VLDL and LDL
A standard lipid panel measures the total amount of cholesterol carried by these lipoproteins. Non-HDL cholesterol (non-HDL-C) is a measure of all of the cholesterol being carried by VLDL, IDL, and LDL [2].
HDL carries cholesterol away from the walls of blood vessels to the liver to be removed. The other three lipoproteins carry cholesterol to the blood vessels and away from the liver. They can deposit cholesterol in blood vessels, causing plaques and hardening of the arteries (atherosclerosis) [2].
HDL reverses this process and is the only lipoprotein that is not associated with an increased risk of heart disease [2].
Non-HDL Cholesterol Test
Your non-HDL-C value is calculated by subtracting your HDL-C value from your total cholesterol value. Your total cholesterol is calculated by adding your HDL-C, LDL-C, and 20% of your triglycerides (an estimate for VLDL). It is tested as part of a standard lipid panel [2].
Non-HDL-C is used to assess your risk of heart disease or to decide on treatment targets for cholesterol-lowering drug therapy.
The benefits of using non-HDL-C include:
- It measures all of the cholesterol that can cause hardening of the arteries (atherosclerosis), including LDL-C
- It is easy to calculate and does not require additional costs and tests besides a lipid profile
- Does not require a fasted sample, unlike LDL-C
Normal Non-HDL Cholesterol Levels
The normal range for non-HDL-C is around 0 – 130 mg/dL or 0 – 3.37 mmol/L.
Non-HDL-C levels, along with all types of cholesterol, are elevated during the second and third trimesters of pregnancy [3].
High Non-HDL Cholesterol
Causes listed below are commonly associated with high cholesterol. Work with your doctor or another health care professional to get an accurate diagnosis. Your doctor will interpret your results, taking into account your medical history, symptoms, and other test results.
Causes
1) High-Carbohydrate Diets
In short-term trials (< 3 weeks), diets high in carbohydrate and low in fat increase non-HDL-C substantially (64 total people) [4, 5, 6, 7].
Longer-term trials (> 3 weeks) show that while VLDL-C (triglycerides) are increased, total cholesterol and LDL-C tend to decrease (131 total people) [8, 9, 10, 11].
2) Obesity
LDL receptors are needed for cells to take in LDL-cholesterol. In obesity, there’s a reduced number of LDL receptors in the body, which means that more LDL stays around in the bloodstream. Obesity also increases the production of VLDL-C and decreases how fast it’s removed from circulation [12, 13].
As a result, multiple studies show that obese people have elevated non-HDL-C levels and that weight loss reduces non-HDL-C [14, 15, 16, 17].
3) Sedentary Lifestyle
Research suggests that a lack of physical activity increases the levels of “bad” cholesterol [18].
4) Hypothyroidism
Thyroid hormones increase the activity of LDL receptors, which remove IDL-C and LDL-C from the blood. Thyroid hormones also increase the conversion of cholesterol to bile acids [19].
There are fewer LDL receptors in people with an underactive thyroid (hypothyroidism). This means that IDL-C and LDL-C increase in the blood. As a result, hypothyroidism increases non-HDL-C levels [20, 21, 22].
Non-HDL-C was also increased in a study of 1443 people with undiagnosed mild (subclinical) hypothyroidism [23].
Taking thyroid hormones reduced high non-HDL-C levels in 39 people with hypothyroidism. Another study of 26 people found that one year of thyroid hormone replacement decreased non-HDL-C in hypothyroidism [24, 22].
5) Smoking
In a study of 75 people, those who smoked had 25% higher non-HDL-C levels compared to non-smokers. Two other studies have also found non-HDL-C levels to be higher in smokers (281 total people) [25, 26, 27].
Another study of 1,500 people found that more cigarettes smoked per day were linked to higher non-HDL-C levels [28].
6) Type 2 Diabetes
Type 2 diabetes increases the risk of heart disease. This is partly due to chronic inflammation and insulin resistance, which increase non-HDL-C levels [29]
As such, non-HDL-C levels are often elevated in people with type 2 diabetes, even when LDL levels are within the normal range [30, 31, 32, 33, 34, 35].
In 339 people with type 2 diabetes, higher non-HDL-C levels were associated with worse diabetes control and higher BMI [36].
7) Infection and Inflammation
Inflammation-promoting cytokines in Inflammation and infection increase VLDL production [37].
H. pylori infection is consistently associated with increased levels of non-HDL-C. Multiple studies of 5,200 people found that getting rid of H. pylori decreases non-HDL-C levels [38, 39, 40, 41, 42, 43, 44, 45].
H. pylori is also linked to a higher risk of heart disease [45, 46].
A meta-analysis of 15 studies with 105k people found that gum inflammation increased the risk of heart disease [47].
In a meta-analysis of 18 studies and 1940 people, gum inflammation was linked to increased levels of non-HDL-C [48].
In a study of 68 people, successful treatment of gum inflammation decreased non-HDL-C. Two studies of 149 people found that gum inflammation treatment reduced non-HDL-C levels [49, 50, 51].
Multiple studies of 597 total people found that non-HDL-C levels were higher in people with psoriasis. One study in 70 people with psoriasis found that nearly 63% had non-HDL-C levels above the normal range [52, 53, 54, 55, 56].
8) Kidney Disease
Kidney disease increases the amount of VLDL the body makes and reduces how fast it’s broken down. As a result, elevated non-HDL-C levels are commonly found in patients with chronic kidney disease [57, 58, 59].
9) Medication
Drugs that can increase LDL and VLDL cholesterol levels include glucocorticoids and water pills (diuretics) [37, 60, 61, 62].
10) Rare Genetic Disorders
Some rare inherited genetic disorders can increase non-HDL cholesterol levels
Non-HDL Cholesterol and Heart Disease
Non-HDL-C is strongly associated with an increased risk of developing as well as dying from heart disease. Scientists have found that non-HDL-C is even better at predicting your risk of heart disease than the traditional risk factor LDL-C [63, 64, 65, 66, 67, 68, 69, 70].
Non-HDL-C is also more closely linked to the underlying mechanisms of heart disease, including inflammation and hardening of the arteries (atherosclerosis), than LDL-C alone [71, 72, 73, 74, 75, 76, 77, 78, 79].
Ways to Decrease Non-HDL Cholesterol
The most important thing is to work with your doctor to find out what’s causing your high non-HDL cholesterol and to treat any underlying conditions. The additional lifestyle changes listed below are other things you may want to discuss with your doctor. None of these strategies should ever be done in place of what your doctor recommends or prescribes!
1) Weight Loss
A meta-analysis of 70 studies found that weight loss substantially decreases non-HDL-C. Losing weight reduces how much cholesterol the body makes [80].
2) Exercise
In a population study of over 80k people, more days per week of aerobic or strength exercise were associated with lower non-HDL-C levels [81].
Simply walking reduced non-HDL-C by 4%, according to a meta-analysis of 22 studies and 948 people [82].
However, a meta-analysis of 13 studies and 404 people found that aerobic exercise didn’t decrease non-HDL-C levels [83].
3) Healthy Diet
The following dietary changes can help reduce non-HDL cholesterol levels:
- Avoid overeating in general. Eat less sugary and processed foods and minimize your intake of saturated and trans fats [84, 85, 5, 86, 87].
- Eat more fiber-rich foods, such as fruits and vegetables [88].
- Increase your consumption of fatty omega-3 rich fish [89].
- Eat more foods high in plant sterols (a type of cholesterol made by plants) including nuts, seeds, and legumes. Plant sterols compete with cholesterol for absorption in the gut, which lowers cholesterol levels [90, 91, 92, 93].
- Mediterranean diet is a good example of a healthy diet rich in monounsaturated fats. It includes lots of fruits and vegetables, fatty fish, olive oil, and nuts [94, 95, 96, 97, 98]
- DASH diet is another type of diet that can help decrease cholesterol levels [99, 100]. This diet is used to lower blood pressure. DASH is, similarly to a Mediterranean diet, rich in vegetables, fruits, lean meats, nuts, and beans. It’s high in fiber and low in fat.
4) Alcohol
In a population study of over 43,000 people, non-HDL-C levels were lower in those who drank alcohol. This effect was seen even in those who drank less than one beer or one small glass of wine a day (10 g) [101].
However, alcohol can increase triglyceride and VLDL-C levels [87, 102]. In addition, excessive alcohol consumption has many negative effects on health. Discuss your alcohol consumption with your doctor.
5) Quit Smoking
Quit smoking. Tobacco increases VLDL-C and non-HDL cholesterol levels [26, 25, 103, 27].
6) Supplements
Discuss the following foods and supplements with your doctor. Research has shown they may help decrease “bad” cholesterol levels:
- Omega-3 (DHA) [87, 104, 105, 106, 107]
- Fiber-rich foods: barley, oats, rice bran [108, 109, 110, 111, 112, 113, 114, 115, 116]
- Nuts, such as walnuts and macadamia nuts [117, 118, 119, 120, 121, 122]
- Beta-glucans [123, 124, 125, 126]
- Glucomannan [127, 128, 129, 130, 131]
- Plant sterols [90, 91, 92]
- Red yeast rice[132, 133, 134, 135].
- Blond psyllium [136, 137, 138, 139].
- Green tea [140, 141, 142, 143].
- Berberine [144, 145, 146, 147]
- Flaxseed [148, 149, 150]
- Avocado [151, 152, 153]
- Probiotic products that contain Lactobacillus strains [154]
- Vitamin C [155]
Remember, always speak to your doctor before taking any supplements, because they may interfere with your health condition or your treatment/medications!
Genetics
Genetics of LDL-C
Some people have reduced the activity of genes that break down cholesterol (ABC transporters). This can increase LDL levels and lower response to cholesterol medication [156].
PCSK9 is a gene that breaks down the LDL receptor, resulting in the accumulation of LDL in the blood. Variants of PCSK9 can cause either elevated or low cholesterol [157].
Familial Hypercholesterolemia
Familial hypercholesterolemia is a disease caused by mutations in several genes, including those that make the LDL receptor (LDLR) and APOB [158].
These mutations cause problems in removing LDL from the blood, resulting in elevated LDL [158].
Genetics of VLDL-C
Lipases
Lipases are a group of enzymes that help to break down VLDL. Mutations in certain genes can result in low levels of the lipoprotein lipase protein and higher VLDL [159, 160].
People with a common mutation in the hepatic lipase gene, have increased VLDL levels and a reduced ability to control VLDL levels with exercise [161].
Apolipoprotein E (ApoE)
ApoE is a protein found in VLDL molecules. As a result of mutations in the gene that encodes the protein, different versions of it exists. Having a defective copy of ApoE contributes to high VLDL levels [162].
