Many people are aware that high cholesterol can cause issues like heart attacks and strokes. How do you know if you have high cholesterol? Does it cause any symptoms? What can you do to lower your cholesterol levels if they’re high?
What affects cholesterol levels?
It’s believed that genetics do play some role in influencing your cholesterol levels. Some people have genetic conditions which cause their cholesterol to be very high. However, for most people, the main effects on your cholesterol levels are lifestyle factors, which are under your control. These include diet, exercise, smoking, and alcohol consumption.
It’s important to note that there are different types of cholesterol. The two main types are:
- Low-density lipoprotein (LDL), or “bad cholesterol.” Higher levels of this type are associated with an increased risk of having a major health issue like a heart attack.
- High-density lipoprotein (HDL), or “good cholesterol.” Higher levels of this type actually protect against heart disease, and are associated with a lower risk of a heart attack.
Your total cholesterol includes both types. However, it’s more important to ensure that your LDL is low enough and that your HDL is high enough. Since your total cholesterol includes both, it’s not as useful of a measurement.
High cholesterol risk factors
Although anyone can potentially develop high cholesterol, there are a few main risk factors for developing high levels of LDL (the dangerous type of cholesterol). These include:
- Obesity (a body mass index, or BMI, of 30 or greater)
- Lack of exercise
- Eating a lot of saturated fat (found in animal products) and/or trans fat (found in packaged foods)
- Drinking too much alcohol
- Taking certain medications
- Certain medical conditions, including diabetes, chronic kidney disease, lupus, hypothyroidism, and HIV/AIDS
- Genetic conditions, like familial hypercholesterolemia
While not all of the causes of elevated cholesterol are under your control, the good news is that many of them are. You can take actions to lower your cholesterol and decrease your risk of having a heart attack or stroke.
High cholesterol signs and symptoms
There are no high cholesterol symptoms. People with high cholesterol generally feel fine, and they often don’t even realize that their cholesterol is high. The only way to make the diagnosis of high cholesterol is through a blood test.
If you have high cholesterol, disease conditions like heart disease are more common, and the risk of heart attacks and strokes is higher.
How to prevent high cholesterol
The best way to prevent high cholesterol is to make healthy lifestyle choices. These include:
- Eat a diet high in fruits and vegetables, and low in animal fats and processed foods.
- Exercise for at least 30 minutes on most days of the week.
- Maintain a healthy body weight.
- Quit smoking.
- Keep alcohol consumption to a moderate level (at most, one drink per day for women and two drinks per day for men), or avoid drinking alcohol altogether.
- Manage stress.
How to know if you have high cholesterol
In order to check your cholesterol, you’ll need a blood test. The National Heart, Lung, and Blood Institute (NHLBI) recommends cholesterol screening:
- Every year for people over age 65
- Every one to two years for men ages 45 to 65, and women ages 55 to 65
- Every five years from age 20 to either 45 (for men) or 55 (for women)
If you have a strong family history of heart disease or high cholesterol, or if you’ve had abnormal cholesterol levels at some point in the past, then it may be recommended that you get screened more often.
You can go to your doctor and ask for cholesterol testing. This may be ordered on a routine basis, when you see your doctor for a physical. However, some people would like to test their cholesterol levels more often, so they can keep track of their own health and make sure that they’re on the right track. They may want to order a cholesterol test at home. For this test, you’ll take your own blood sample using a fingerprick, and mail this back to the lab for testing. Your results then come over the phone.
Your cholesterol test results should include:
- Total cholesterol
Remember that you want HDL to be high, and LDL to be low. Often, you’ll also get a report of the LDL/HDL ratio, which is simply calculated from your tested levels. You want this number to be as low as possible.
Can high cholesterol cause a heart attack?
There is a strong link between cholesterol and heart disease risk. In particular, high LDL cholesterol is associated with the risk of a heart attack. The excess cholesterol deposits into the walls of the arteries, making them narrower and stiffer. This can reduce blood flow to the heart. If a small piece of this excess cholesterol breaks off, it can trigger the formation of a blood clot. The clot can block the blood flow to the heart, leading to a heart attack.
Can high cholesterol cause a stroke?
In addition to increasing the risk of a heart attack, high cholesterol also increases the risk of a stroke. The mechanism is the same as for heart attacks, but when it occurs in the arteries of the brain, high cholesterol causes strokes.
Can high cholesterol cause heart palpitations?
Some heart palpitations may be caused by cardiac arrhythmias, or an irregular heartbeat. Research does suggest that high cholesterol increases the risk of cardiac arrhythmias, probably by interfering with blood flow to the heart. However, heart palpitations could also mean that you have heart disease, so it’s very important to get checked by a doctor if you have high cholesterol and heart palpitations.
Blood Cholesterol Diagnosis. National Heart, Lung, and Blood Institute (NHLBI). https://www.nhlbi.nih.gov/health/blood-cholesterol/diagnosis. Accessed 20 October 2022.
Blood Cholesterol Causes and Risk Factors. National Heart, Lung, and Blood Institute (NHLBI). https://www.nhlbi.nih.gov/health/blood-cholesterol/causes. Accessed 20 October 2022.
Goonasekara C, Balse E, et al. Cholesterol and cardiac arrhythmias. Expert Rev Cardiovasc Ther. 2010 Jul;8(7):965-79. doi: 10.1586/erc.10.79.
High Cholesterol. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/symptoms-causes/syc-20350800. Accessed 20 October 2022.
High Cholesterol Diseases. Cleveland Clinic. https://my.clevelandclinic.org/health/articles/11918-cholesterol-high-cholesterol-diseases. Accessed 20 October 2022.