A low high-density lipoprotein (HDL) cholesterol level can increase your risk of heart disease and stroke, especially when coupled with "bad" low-density lipoprotein (LDL) cholesterol that's too high. Lifestyle changes to address some of the causes, such as improved diet and exercise, can boost "good" HDL that removes cholesterol from your bloodstream.
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Illustration by Emily Roberts for Verywell Health
1. Excess Weight
If you are overweight or diagnosed with obesity, a type of blood fat called triglycerides likely will increase. HDL is composed of triglycerides and, when triglyceride levels are high, HDL will undergo changes that cause it to break down faster, leading to a lower count.
Losing 5% of your body weight is a reasonable short-term goal to address overweight and obesity. Over the longer term, losing 15% of your body weight and remaining at this weight is considered a good result. Some studies note that these goals vary with the individual.
Working with a healthcare provider, personal trainer, and/or nutritionist can ensure that your weight-loss plan is safe and effective.
2. Diet and Nutrition
A diet high in refined carbohydrates (such as white bread and sugar) causes the liver to produce more triglycerides, resulting in a drop in HDL. Some foods you eat are also rich in triglycerides, including:
- Fried foods
- Processed foods
- Red meat
- High-fat dairy
To counter this, limit your intake of refined carbs and saturated fats found in animal-derived foods. Instead, substitute with whole grains and healthier monounsaturated and polyunsaturated fats. These are found in plant-based foods.
3. Lack of Exercise
A lack of exercise is associated with the buildup of fatty deposits in arteries called atherosclerosis. Exercise improves HDL's ability to scoop up these fatty deposits and move them to the liver for disposal (a process known as cholesterol efflux).
Aerobic exercise is known to increase HDL levels. Studies have shown that the duration of aerobic exercise, as opposed to intensity, is the main factor associated with benefits but more study is needed to understand why.
Try to get 150 minutes of moderate intensity exercise or 75 minutes of aerobic exercise each week. A combination of the two can include moderate dancing or brisk walking, along with:
- More intense running
- Faster bicycling
- Intense lap swimming
4. Smoking
The chemicals in tobacco smoke can lower HDL levels in different ways, and research studies confirm the effects of smoking on HDL. However, the precise reasons are not fully understood.
Some studies point to interaction with proteins called cholesterol ester transfer protein (CETP) and fats called lecithin, both of which are needed to build HDL, but the results are mixed. Smoking also appears to affect liver function that's important to cholesterol and triglyceride levels.
Quitting cigarettes can be hard, but you can succeed. Speak with your healthcare provider about smoking cession aids, many of which are fully covered by health insurance under the Affordable Care Act.
5. Uncontrolled Diabetes
Low levels of HDL and the risk of type 2 diabetes are closely linked, although more study is needed to fully understand why. Insulin resistance, for example, is associated with both low HDL levels and the development of type 2 diabetes.
Some studies point to the role of apolipoprotein A1 (ApoA1), which is needed to produce HDL, because it appears to influence the development of diabetes and other metabolic diseases. The low HDL levels seen in people with chronic kidney disease also may be related to ApoA1.
Researchers are even looking at ways that treatments based on ApoA1 levels can be used to manage blood sugar in type 2 diabetes. It's essential to avoid poorly controlled diabetes, so speak with your healthcare provider about any needed changes to your diet, exercise, or diabetes medication.
HDL and Metabolic Syndrome
A low HDL level is one of five factors considered as part of a diagnosis of metabolic syndrome when at least three factors are present. In addition to HDL, the other factors include:
- High blood glucose (sugar)
- High triglycerides
- High blood pressure
- Large waist circumference (apple-shaped body)
Metabolic syndrome can lead to heart disease, stroke, diabetes, and kidney disease.
6. Medication
Certain medications are known to lower HDL levels. Some of these are used to treat heart disease, while others affect hormones that can indirectly affect the production of lipoproteins.
These include:
- Beta-blockers: Most often used to treat irregular heartbeats and angina
- Thiazide diuretics: A type of "water pill" used to treat high blood pressure
- Androgens: Male hormones, most specifically testosterone
- Progesterone: Commonly used in hormonal birth control
- Anabolic steroids: Used for rapid muscle growth and bodybuilding
Do not stop any prescribed drug or alter the dose without first speaking with your healthcare provider.
7. Genetic Mutations
Sometimes, a very low HDL count is caused by genes that run in families. These include conditions like Tangier’s disease, caused by mutations in the ABCA1 gene, and another called familial hypoalphalipoproteinemia, caused by mutations of the APOA1, ABCA1, or LCAT genes.
Optimal HDL Levels
Cholesterol levels are checked with a simple blood test called a lipid panel. HDL counts are described in milligrams per deciliter of blood (mg/dL).
Optimal HDL levels can vary by a person's age and/or assigned sex at birth, as follows:
- People 19 and under: Greater than 45 mg/dL
- Males over 20: Greater than 40 mg/dL
- Females over 20: Greater than 50 mg/dL
Anything below these values is considered HDL deficiency. While an HDL count is just one factor in overall health, it can direct actions to reduce risk, including smoking cessation, changes in diet. Medications such as statins can be used to reduce "bad" LDL cholesterol, too.
Cardiovascular Risk Assessment
Your HDL results are considered with other factors when completing a cardiovascular risk assessment. This evaluation of your 10-year and lifelong risk of heart disease includes factors such as:
- Your age and assigned sex at birth
- Your personal and family history of heart disease
- Results of metabolic tests including blood pressure, glucose, total cholesterol, and weight
- Lifestyle factors such as exercise, diet, stress, smoking, and socioeconomic status
Key Takeaways
- HDL is the "good" cholesterol that helps remove cholesterol from your arteries. Higher levels are considered better for heart health. Normal levels are at least 40 mg/dL for adult males and 50 mg/dL for adult females.
- HDL is only one measure but it can suggest lifestyle changes are needed to put you in control of your weight, diet, smoking habits, and other risk factors.
- Talk with your healthcare provider about how often you should have your cholesterol checked (a common test with your annual physical) and what your results mean in terms of any treatment.
Cholesterol Healthcare Provider Discussion Guide
Get our printable guide for your next healthcare provider's appointment to help you ask the right questions.
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