Diabetes is a disease that affects much more than just blood sugar.
People with type 1 diabetes and type 2 diabetes are at higher risk of developing complications from chronic high blood glucose, such as an increased cardiovascular risk.
High cholesterol, on its own, is a risk factor for developing heart disease. However, when someone has both high cholesterol and type 2 diabetes, the risk of heart disease is even greater.
In this article we will discuss the relation between cholesterol and diabetes and explain why managing cholesterol levels should be among the top priorities for anyone with diabetes.
What is Cholesterol?
Cholesterol is a waxy, fat-like substance that is necessary for our bodies to function.
Cholesterol helps produce important hormones as well as vitamin D and is found in all of our cells. Our body produces all the cholesterol we need to survive.
Certain foods also contain cholesterol, such as egg yolks, meat, and other animal products. Cholesterol isn’t obtained from eating plant foods, though plants do make minimal amounts of cholesterol.
LDL cholesterol is considered bad because it tends to increase heart disease risk. On the other hand, HDL cholesterol is associated with a decreased risk of heart disease.
HDL cholesterol can help lower levels of bad cholesterol by helping to carry it from the arteries to the liver to be excreted. HDL cholesterol isn’t enough to lower bad cholesterol all by itself, though. It’s estimated that only about ⅓-¼ of LDL cholesterol levels are carried away by HDL cholesterol.
Dyslipidemia, or a high cholesterol level, is part of a condition called metabolic syndrome. Metabolic syndrome is a risk factor for developing type 2 diabetes, as well as heart disease and stroke.
The aspects of metabolic syndrome include:
- Abnormal cholesterol and triglyceride (lipid) levels
Increased body fat around the waist (waist circumference >40 inches for men and >35 inches for women) because fat is more likely distributed around the heart.
Cholesterol is primarily manufactured in the liver, so not all of our cholesterol comes from how we eat. While cholesterol can be impacted by lifestyle, it’s important to know that part of high cholesterol can be due to familial hypercholesterolemia.
This means that unhealthy cholesterol levels can run in your family and be passed down in your genes. People with familial hypercholesterolemia tend to have very high levels of LDL cholesterol and may even have heart issues at younger ages.
By taking steps to manage cholesterol, individuals can reduce their chance of cardiovascular disease and premature death.
Cholesterol level guidelines
Cholesterol targets will vary based on someone’s risk for atherosclerotic cardiovascular disease (ASCVD). If someone is at a low risk of heart disease, having borderline high cholesterol wouldn’t be as dangerous as someone at high risk of heart disease.
he American Heart Association (AHA) states that diabetes often lowers HDL (good) cholesterol levels and raises triglycerides and LDL (bad) cholesterol levels. Both of these increase the risk for heart disease and stroke.
As a reminder:
- An LDL cholesterol level under 100 milligrams/deciliter (mg/dL) is considered ideal.
- 100–129 mg/dL is close to ideal.
- 130–159 mg/dL is borderline elevated.
The link between diabetes and high cholesterol
Diabetes affects many different aspects of a person’s overall health. All of our body’s systems rely on healthy blood supply. When sugar is too high, it can cause damage to the vessels and arteries that supply blood to our body.
This is why diabetes has such a significant impact on heart health. People with diabetes are two to four times more likely to die from cardiovascular disease than those without diabetes.
Diabetes tends to alter blood lipid (fat) levels, which is called diabetic dyslipidemia. Lipids are the term for blood fat, which includes cholesterol as well as triglycerides.
Diabetic dyslipidemia occurs when levels of high-density lipoproteins (HDL, or good cholesterol) are low, and levels of low-density lipoproteins (LDL, or bad cholesterol) are high. (Think HDL is “happy” for good, and LDL is “lousy” for bad.)
Studies have found that insulin resistance, which is one of the causes of type 2 diabetes, maybe a precursor for diabetic dyslipidemia. Having high levels of LDL (bad) cholesterol can lead to atherosclerosis. This is the buildup of waxy fats in the arteries, which can cause hardening and narrowing of the arteries.
If an artery to the heart becomes blocked, a heart attack can occur. If an artery to the brain becomes blocked, a stroke, or cerebrovascular accident (CVA), can occur.
Complications of high cholesterol
Those with uncontrolled diabetes are considered at higher risk for heart disease. Therefore they may be recommended to start treatment for their high cholesterol sooner.
Patients with diabetes should follow-up with their healthcare provider regularly and have a lipid panel blood test at least once a year. If cholesterol levels are very high, your healthcare provider may want to recommend treatment and re-check sooner, such as in 3-6 months, to assess progress.
Heart disease risk increases, the longer someone has diabetes. If someone is newly diagnosed with diabetes and is also found to have high cholesterol, their healthcare provider may be comfortable trying lifestyle changes first before starting a cholesterol-lowering medication.
On the other hand, if someone has had diabetes for years and their blood sugars are uncontrolled, cholesterol-lowering medication is more likely to be recommended.
Treatment options for high cholesterol
Statins are a class of medications used to help lower high cholesterol. Their intensity level classifies them, or the ability to lower cholesterol.
Statins work by blocking certain liver enzymes responsible for manufacturing cholesterol. Statins tend to lower LDL and raise HDL levels, which is ideal.
High-intensity statins can lower LDL cholesterol by approximately 50% or more. Atorvastatin (Lipitor) at 40-80 mg daily and Rosuvastatin (Crestor) at 20-40 mg daily are both examples of high-intensity statins.
Moderate-intensity statins can lower LDL cholesterol by approximately 30-50%. Lipitor and Crestor at lower doses are considered moderate-intensity.
Low-intensity statins include lower doses of many of the moderate-intensity statins.
Statins are known to cause a variety of side effects, which may deter some people from starting them. The most common side effects of statins include:
- Difficulty sleeping
- Muscle aches
- Nausea or vomiting
- Abdominal pain
- Chronic cough, in rarer cases
People who don’t tolerate statins are said to have statin intolerance. Speaking to your healthcare provider about your side effects is essential. Statins are prescribed because the perceived benefit is greater than the risks, including adverse side effects.
Some studies have found an association between taking statins and a slightly increased risk (9%) of developing type 2 diabetes. However, the overall risk is still low, especially when compared to the risk of developing heart disease.
Researchers recommend that no changes be made to prescribing statins for moderate- and high-risk individuals, despite this finding.
If you are hesitant about starting a statin, have an in-depth discussion with your healthcare provider.
How to naturally lower cholesterol levels
For those with moderately-high cholesterol and who aren’t at high risk of heart disease, lifestyle modifications are the first recommended course of treatment.
Natural treatments include lifestyle changes and non-prescription vitamins and supplements.
- Cholesterol in foods: One of the most well-known links to cholesterol levels is diet. All animal products contain cholesterol. Some foods like eggs, organ meat, and shellfish are particularly high in cholesterol.
The recommendations behind diet and cholesterol seem always to be changing, which can be frustrating! The bottom line is that if you have high cholesterol, it’s probably a good idea not to eat large amounts of foods high in cholesterol regularly. Aim for a balance, with some cholesterol-containing foods and plenty of plant foods free of cholesterol.
- Saturated fat tends to raise both LDL and HDL cholesterol levels. Saturated fat is found in animal products like meat, full-fat dairy, and some plants, such as coconut. Saturated fat is okay to eat, but it should be in moderation. If you have high cholesterol and eat a large amount of saturated fat, it may be beneficial to try cutting back on it.
- Trans fats, on the other hand, are considered the least heart-healthy of the fats. Trans fat can raise LDL cholesterol and lower HDL cholesterol. Trans fat primarily comes from processed foods, such as those with partially hydrogenated oils. In 2018, the Food and Drug Administration (FDA) banned the use of trans fats in products, which has been effective since May 2019.
- Unsaturated fats, such as monounsaturated and polyunsaturated fats, are considered the most heart-healthy. They have been associated with reduced risk of heart disease.
- Omega-3 fatty acids are also considered heart-healthy, reducing inflammation. Sources of unsaturated fats include nuts, seeds, plant oils, avocados, and fatty fish like salmon.
- Fiber: Dietary fiber is found in plant foods such as fruits, vegetables, nuts, seeds, whole grains, and legumes. There are two types of fiber: soluble and insoluble.
Soluble fiber, such as the kind found in oats, legumes, flax seeds, apples, berries, and broccoli, is especially helpful for lowering cholesterol levels. Some people prefer to get their daily soluble fiber intake through a fiber supplement such as psyllium fiber.
- Physical activity: Being active can help boost HDL cholesterol levels, as well as reducing blood sugar levels. The American Diabetes Association a weekly goal of 150 minutes of physical activity per week. The ADA also recommends not going longer than two days without being active.
- Stop smoking: Smoking can lower HDL cholesterol and raise LDL. Quitting smoking not only reduces heart disease risk but can help improve cholesterol, which impacts overall heart health.
- Plant sterols and stanols: Sterols and stanols are substances found in plants that help block the absorption of cholesterol. Studies find that intakes up to approximately three grams per day of plant sterols and stanols can lower LDL cholesterol by an average of 12%.
- Other natural vitamins and supplements: Niacin (vitamin B3) and red rice yeast are popular natural supplements for lowering cholesterol. Some people prefer to try these before starting a statin. As always, it’s best to have a conversation with your healthcare provider about your treatment options for high cholesterol.
Cholesterol is crucial for our health but is potentially dangerous when levels become abnormal. HDL is considered good cholesterol, and LDL is bad cholesterol. High levels of LDL and low levels of HDL are risk factors for the development of the cardiovascular disease.
People with diabetes are at increased risk of abnormal cholesterol and heart disease. Monitoring abnormal cholesterol levels is vital for heart health.
Medications called statins are prescribed to help lower LDL and raise HDL levels. These medications come with some possible side effects, as all medications do. Some people don’t tolerate certain statins. In this case, it’s important to address side effects with your healthcare provider to look into alternative treatments.
Natural steps to lower cholesterol include replacing saturated fat with unsaturated fat, increasing dietary fiber intake, getting regular physical activity, and quitting smoking.