The Link Between High Cholesterol & High Blood Pressure – A Comprehensive Guide

High blood pressure (hypertension) is one of the most prevalent human conditions. It affects more than 1.28 billion people worldwide¹ and about a third of all Americans (roughly 116 million people²). The condition has been linked to various factors, including cholesterol levels.

High cholesterol is one of the leading causes of hypertension (and other serious and usually chronic conditions). Let’s take a comprehensive look at the relationship between these two conditions.

Defining high cholesterol

Cholesterol is a fat-like, waxy substance present in every cell in your body.

Cholesterol is not wholly bad. It is essential for the body's production and development of cells, hormones, vitamin D, and some digestive juices. However, it comes in varying types, some good, others bad.

Good cholesterol

Good cholesterol is also referred to as ‘high-density lipoprotein’ (HDL). It is considered good because it removes the ‘bad’ cholesterol from the blood vessels and transports it to the liver to be destroyed and expelled from the body.

However, it is worth noting that too much good cholesterol in your blood isn't healthy either. The healthy range is 40–60mg per deciliter.

Bad cholesterol

Bad cholesterol is also referred to as ‘low-density lipoprotein’ (LDL) or ‘very-low-density lipoprotein’ (VLDL). High levels of LDL and VLDL cause a buildup of a plaque-like substance on your blood vessel walls. This substance gets harder over time, eventually causing the arteries to narrow (a condition called ‘atherosclerosis’), which interferes with the normal blood flow and leads to an increase in blood pressure.

A healthy amount of bad cholesterol³ in the blood is under 100mg per deciliter. Here is a summary of how bad cholesterol is measured and classified:

Defining high blood pressure

Blood pressure is the force of the blood flowing through your arteries and other blood vessels. High blood pressure – hypertension – is characterized by the force of blood flowing against your blood vessel walls being consistently higher than normal. 

Blood pressure measurement is based on two values:

• Systolic pressure (the pressure in the blood vessels when the heart pumps)

• Diastolic pressure (the pressure when the heart relaxes)

High blood pressure is diagnosed when the systolic pressure is at least 130mm Hg, and the diastolic pressure is at least 80mm Hg. The blood pressure reading must be taken at various times on different occasions for a diagnosis to be made, as blood pressure can change temporarily.

The relationship between high cholesterol and high blood pressure

Hypertension and high cholesterol are two separate conditions with different risk factors. However, high cholesterol is a risk factor for high blood pressure. The two conditions are often diagnosed together – most people with high blood pressure also have high cholesterol, and most people with high cholesterol are likely to develop hypertension in the near future. 

The effects of high cholesterol on blood vessels

As explained earlier, bad cholesterol is difficult to remove and is stored along the lining of your blood vessel walls. The waxy substance turns into a hard, plaque-like substance over time, which is even tougher to remove.

Over time, multiple layers of this plaque-like substance form inside the blood vessels, making the walls hard and the space inside the veins and arteries narrower and narrower.

The effects of cholesterol buildup on blood pressure

The heart pumps blood with just enough power to push it through the narrow blood vessels. The passageways through blood vessels get narrower and narrower as bad cholesterol builds up. This increases the resistance of the flowing blood against the narrowed artery walls, and the increased resistance leads to elevated pressure. The heart is forced to pump harder to get blood through the narrower vessels to all the other organs.

This tires the heart's muscles over time and causes tears and cracks in the blood vessels. The tears in the blood vessels create more openings for bad cholesterol to occupy, further worsening the problem.

Cholesterol continues building up as more of it enters the body. Eventually, the elevated resistance of the blood flow and the higher blood pressure can cause a rupture in blood vessels or the formation of blood clots, resulting in a heart attack or stroke.

What is labile hypertension?

Hypertension has several risk factors besides high cholesterol. Stress is one of the common risk factors – it is not uncommon for blood pressure levels to change slightly depending on your mood.

Labile hypertension refers to a sudden increase in your blood pressure from normal to abnormally high, often above 130/80 but not extremely high, usually because of stress and other negative emotions. The high pressure goes back to normal after a short period of time. As such, high cholesterol doesn't necessarily influence labile hypertension.

Other conditions linked to high cholesterol

As we’ve seen, bad cholesterol can line the walls of all blood vessels in your body. This can have varying impacts on your overall health and result in the following conditions:

Type 2 diabetes

Type 2 diabetes is both an effect of and risk factor for cholesterol. Besides affecting the blood sugar level, diabetes also affects the amount of LDL (bad cholesterol) and HDL (good cholesterol) in the blood. This can result in a condition called ‘diabetic dyslipidemia⁴,’ characterized by high levels of LDL and low levels of HDL.

Recent studies⁵ have also found that hyperlipidemia, especially high triglyceride, can be a risk factor for developing diabetes.

Additionally, diabetes causes cracks in the blood vessel lining. It essentially creates more spaces for the body to store cholesterol, contributing to the gradual blockage of blood vessels.

Coronary heart disease

Coronary heart disease is a common effect of bad cholesterol buildup. As explained, bad cholesterol lines the blood vessels from the heart (the coronary arteries), straining blood flow. The heart responds by pumping faster and harder, straining and fatiguing the cardiovascular muscles.

The reduced blood flow to the heart plus its increased activity causes angina, a condition characterized by mild-to-severe chest pains.

Peripheral arterial disease

Peripheral arteries are blood vessels located outside the brain and heart. Peripheral arterial disease (PAD) occurs when bad cholesterol is lining a significant portion of these blood vessels. The cholesterol makes the vessels hard and inflexible. It also reduces the space inside them and increases the pressure of blood flow.

PAD commonly affects blood vessels channeling blood to the legs and feet, resulting in mobility issues. It also affects blood flow to the kidneys and other vital organs, which may lead to organ damage or failure.

Stroke

The brain needs a constant supply of blood to function optimally. Insufficient blood supply can damage and kill brain cells, causing a stroke.

A stroke is highly likely to occur when one of the many blood vessels that channel blood to the brain is blocked by a clot (ischemic stroke) or ruptures (hemorrhagic stroke). As explained, cholesterol can make blood vessels narrow, so blood clots are more likely to form, or could cause the vessels to rupture from increased blood pressure. 

Risk factors for developing high cholesterol

While genetics may influence⁶ the ability of your body to remove bad cholesterol, high cholesterol is often caused and influenced by other factors, including: 

• Obesity (having a body mass index of 30 or more)  

• Smoking tobacco, and drinking alcohol excessively 

• Lack of exercise

• Unhealthy eating habits 

• Age (older people are at greater risk of developing high cholesterol) 

Some of these risk factors have more influence over the likelihood of developing high cholesterol than others. Fortunately, most of them are within your control. 

It is also worth noting that certain medical conditions can elevate the blood’s cholesterol levels. These conditions include:

• Diabetes 

• Hypothyroidism 

• Liver disease 

• Lupus

• HIV

• Kidney disease

• Cushing syndrome 

Additionally, some medications can worsen the lipid profile, elevating cholesterol and triglycerides. These medications include:

• Immunosuppressants

• Diuretics

• Antidepressants

• Oral estrogen

• Beta-blockers

• Corticosteroids

In this case, the doctor will study the relationship between your different medical conditions and prescribe safe medication. 

Preventing and managing high cholesterol

It is important to avoid accumulating bad cholesterol, but don't worry if you already have high cholesterol levels – there are ways to manage and reverse it.

Healthy dieting

Most of the cholesterol (good and bad) comes into the body through the food you eat. An unhealthy diet will give your body a steady supply of bad cholesterol, while a healthy one will help keep your blood vessels plaque-free and healthy. 

Generally, it is advisable to switch from processed and fast foods⁷ to natural foods containing unsaturated fats. Some of the foods to avoid include: 

• French fries 

• Fried chicken 

• Potato chips 

• Onion rings 

• Red meat 

• High-fat dairy products 

Some of the recommended foods include: 

•  Fish (and other lean sources of protein) in place of red meat 

• Fruits and vegetables 

• Whole grains and legumes 

Overall, it is advisable to avoid fried foods and replace them with boiled, steamed, and roasted foods instead. You should also consult your doctor or a nutritionist if you are allergic to certain foods. 

Exercising

Exercising is known to prevent and reduce high cholesterol levels⁸ in several ways. The most obvious way is by reducing your body mass index, one of the risk factors of high cholesterol. 

Exercising also helps produce certain enzymes and hormones that help remove bad cholesterol. It is worth noting that exercising helps with many of the symptoms of high cholesterol and the conditions caused by it. 

Healthy lifestyle

Your lifestyle affects your overall health, including the amount of cholesterol in your blood⁹. As mentioned, excessive smoking and drinking are two of the leading risk factors for high cholesterol. 

Smoking reduces the amount of good cholesterol in the blood while increasing the amount of LDL, in addition to posing a range of other health risks. Excessive drinking does the same thing and can also increase blood pressure over time. 

Occasionally drinking moderate amounts of red wine¹⁰ can help flush out some of the bad LDL. However, smoking is never recommended under any circumstance as it doesn't have any known health benefits. 

Medication

Your doctor can prescribe medicine to help manage and lower high cholesterol levels¹¹, especially when risks such as hypertension and heart attacks are likely. The prescribed medication will depend on the amount of cholesterol in your body and other underlying risk factors. 

Risk factors for high blood pressure

High cholesterol is not the only cause of high blood pressure. Other notable risk factors include: 

• Excessive smoking and drinking 

• Obesity 

• Unhealthy eating habits 

• Too much salt 

• Lack of physical activity 

• Diabetes

• Chronic stress

High blood pressure and high cholesterol share many risk factors. Fortunately, hypertension, in many situations, is preventable and manageable. 

Preventing and managing high blood pressure

Preventing and managing hypertension entails adopting a generally healthy lifestyle. This includes the following: 

• Eat a healthy and balanced diet (including fruits and vegetables)

• Exercise more and be physically active in general

• Avoid excessive consumption of alcohol and tobacco

• Avoid foods containing saturated fats or excess salts

• Manage your stress and anxiety levels

• Get diagnosed and take the prescribed medicine

Food that can help to lower and manage cholesterol is also recommended for preventing and managing hypertension. Consult your doctor or a dietician when determining what to eat. It is also advisable to consult a fitness expert when developing an exercise plan, as some exercises can be too intense for your heart if you are suffering from any cardiovascular condition. 

Hypertension is often called a ‘silent killer’ because in its mild and moderate form, symptoms don’t always appear. The WHO and other health organizations estimate that less than half of all people¹² with hypertension get diagnosed and treated – many live with high blood pressure without knowing it or taking the necessary measures to lessen its symptoms.

Diagnosis is important when developing a strategy to manage your high blood pressure, so get your blood pressure measured regularly. Hypertension can often present with no symptoms, but occasionally, especially when severe, symptoms may manifest such as: 

• Headaches and nosebleeds 

• Chest pains 

• Shortness of breath

• Dizziness

• Blood spot in the eyes

• Facial flushing

• Blood in urine

Unfortunately, the condition only gets worse over time without the right care. It is advisable to get your blood pressure tested at every medical checkup. 

The lowdown

High cholesterol is one of the biggest risk factors for high blood pressure. Fortunately, in most cases, you can control the amount of bad cholesterol in your body through healthy dieting, exercising, and adopting a generally positive lifestyle.

Keeping your cholesterol levels in check will help prevent and manage hypertension and other related conditions such as diabetes and obesity.