High Cholesterol, Heart Health & You: Understanding the Basics
Medically Reviewed by Dr. Samantha Miller, MBChB
Cholesterol is a fatty substance your body obtains from your diet, and your liver also manufactures it. It’s essential for many bodily functions — such as cell renewal, transport of substances around your body and the synthesis of hormones — and it forms an integral part of the membranes of all your body’s cells. Our bodies are able to manufacture all the cholesterol we need, so most of us typically don’t need to consume large amounts of this substance via our diets. That’s why we’re encouraged to limit our dietary intake.
Cholesterol travels around your body with lipoproteins, which are particles that have the ability to transfer oils through water. There are several types of lipoproteins, the most notable being low-density lipoprotein (LDL) and high-density lipoprotein (HDL). LDL is often referred to as “bad” cholesterol; one of its roles is to transport cholesterol to blood vessels, where it can form atherosclerotic plaques. Over time these plaques can narrow or even block blood vessels, leading to blood clots, heart attacks and strokes. In contrast, HDL is often referred to as “good” cholesterol because its role is to carry cholesterol away from the vessels and into the liver, where it can be processed and eliminated from your body.
Causes and Risk Factors for High Cholesterol
Although you cannot control the genetic factors that may increase your risk of developing high cholesterol, such as being assigned male at birth or having a family history of hypercholesterolemia, there are certain things you can do to lower your risk of developing it. Having a BMI (body mass index) over 30 increases your risk of having high cholesterol, particularly if you carry excess weight around your waist. Smoking, not getting enough exercise and eating a poor diet are also known to correlate with the disease. Having Type 2 diabetes is also associated with a higher risk of developing high cholesterol.
There’s a genetic condition called familial hypercholesterolemia in which your body has a mutation in one of the genes responsible for metabolizing cholesterol. This leads you to have very high cholesterol levels. If you have a family member with high cholesterol, particularly if they were diagnosed at a young age, it’s worth having your healthcare provider check to see if you may have this inherited form.
Symptoms of High Cholesterol
High cholesterol, often called hypercholesterolemia, typically has no specific symptoms. The only way to know if you have abnormal levels of this fat is through a blood test. If symptoms do manifest, they’re likely to be due to a complication of high cholesterol, such as cardiovascular disease. Often the first physical sign of high cholesterol is a heart attack or stroke.
Diagnosing High Cholesterol
High cholesterol is diagnosed via a blood test. A test called a lipid panel reports your total cholesterol, your LDL cholesterol, your HDL cholesterol and your triglycerides (a type of fat in the blood). For the most accurate results, you should fast for 12 hours before having your blood drawn for this test.
Normal levels vary from lab to lab, but according to the U.S. National Library of Medicine, the following are normal:
- Total cholesterol:
- LDL cholesterol:
- HDL cholesterol: >60 mg/dL
Total cholesterol between 200-239 mg/dL is borderline high, and >240 mg/dL is high. LDL cholesterol between 130-159 mg/dL is borderline high, and above 160mg/dL is high. HDL cholesterol below 40 mg/dL for men and 50 mg/dL for women is considered to be low.
Treating High Cholesterol
Lifestyle changes are the first lines of defense to start bringing your cholesterol to manageable, healthy levels. Weight loss and dietary changes are the most effective ways to lower your cholesterol. Losing 10 pounds can drop your LDL cholesterol by up to 8%. Decrease the number of trans fats (found in baked goods and fried foods) in your diet to lower your LDL and raise your HDL. Aim to exercise for at least 2.5 hours per week. Add more nuts, fish and fiber to your diet, and opt for fruits and vegetables rather than chips and cake.
If changes in your lifestyle alone don’t lower your cholesterol, your doctor may opt to incorporate medications. The medication or combination of medications the doctor finds appropriate for you depends on various factors, such as your age, current health and possible side effects. Statins are a type of medication that work to block a substance (HMG-CoA reductase) that your liver requires to synthesize cholesterol. Bile acid-binding resins prompt the liver to produce more bile, which contains cholesterol, thus reducing the level of cholesterol in your blood and promoting its elimination. Fibrates lower LDL and increase HDL cholesterol levels.
Preventing High Cholesterol
You can prevent high cholesterol by eating a healthy diet and maintaining an active lifestyle. You should aim to reduce your intake of trans and saturated fats. Foods that are high in these types of fats include animal products such as red meat, cheese and dairy products; baked goods; fried foods; and fast foods. Many types of snacks, such as chips and cakes, are also high in trans and saturated fats. Instead, aim to eat more fiber and unsaturated fats, such as whole grains, fruits and vegetables.
Always take your personal health into account when making dietary decisions. The general guidelines from the American Heart Association indicate that your cholesterol intake should be less than 300mg per day. If you have high cholesterol already, try reducing that number to 200mg a day. Ask your doctor if you have any concerns about your cholesterol levels or your diet.
Staying at a healthy weight is also key to preventing multiple health ailments, not just high cholesterol. Being at a healthy weight for your height helps to ward off diabetes, lung diseases, cardiovascular disease and even cancer. Being more active and engaging in at least 150 minutes of physical activity each week — such as a 30-minute walk five times a week — helps your body and metabolism stay healthy and active.
If you’re worried about your cholesterol, the first step is to get checked. Visit your doctor and ask if there’s anything you should be doing to treat or prevent hypercholesterolemia.