The CDC reports that every year in the US, more than 795,000 people have a stroke — with around 610,000 of those being their first one. Furthermore, someone has a stroke every 40 seconds, and every 3 minutes, someone dies from one. 

Strokes are serious events that can have even more serious health consequences. Let’s explore what it means to have a stroke including the types of stroke, modifiable risk factors for stroke, and stroke prevention guidelines to protect yourself. 

What is a Stroke?

A stroke, also called a cerebrovascular accident (CVA), happens when blood flow to a part of your brain is disrupted. When this occurs, your brain tissue doesn’t receive the oxygen and nutrients it needs, which can cause brain cells to start dying within minutes. 

Stroke Symptoms

Some of the most common indications of a stroke include: 

• Sudden weakness or numbness in the face or limbs
• Facial drooping and paralysis on one or both sides of the face
• Confusion
• Trouble speaking or understanding speech
• Difficulty walking
• Severe headache
• Dizziness

Strokes can cause serious and sometimes irreversible damage, reinforcing the importance of acting FAST (an acronym for Face drooping, Arm weakness, Slurred speech, Time to call 911) when you or someone around you is showing signs of stroke. 

What Are the Different Types of Strokes?

Strokes are broadly classified into two main types: ischemic strokes and hemorrhagic strokes. 

Ischemic Strokes 

These occur when a blood clot blocks or narrows an artery leading to the brain. This blockage reduces blood flow depriving your brain tissue of oxygen and nutrients. This is what causes cell damage that can sometimes be irreversible.

There are also two main subtypes underneath ischemic strokes, which include: 

• Thrombotic stroke: Caused by a blood clot (called a thrombus) forming in one of the arteries supplying blood to the brain. This clot usually develops in an area damaged by atherosclerosis, a buildup of plaque and fatty deposits in your arteries. 
• Embolic stroke: A blood clot forms elsewhere in the body (like the heart) and travels through the blood until it becomes lodged in a smaller artery within the brain.

Hemorrhagic Strokes

These are caused when a blood vessel ruptures and bleeds in the brain. This can damage nearby cells and increase pressure within the skull, causing more damage.

There are two main types of hemorrhagic stroke as well: 

• Intracerebral hemorrhage: A blood vessel in the brain ruptures and leaks blood into the surrounding brain tissue, damaging cells and causing swelling.
• Subarachnoid hemorrhage: Often triggered when an aneurysm (a weakened area of a blood vessel) ruptures, causing bleeding between the brain and surrounding tissues. 

Stroke Risk Factors

Who can have a stroke? Well, anyone — but certain stroke risk factors are important to understand.

Modifiable risk factors for stroke are ones you can change by making different choices or speaking with your healthcare provider for other options:

• Having high blood pressure, because of how it damages your arteries over time and makes them more susceptible to blockages and damage
• Smoking, because tobacco use damages your blood vessels and increases the risk of blood clots forming
• High LDL, often called “bad” cholesterol because of how it promotes the buildup of plaque in the arteries
• Having diabetes, as poorly-controlled blood sugar can damage blood vessels over time
• Obesity and a sedentary lifestyle increase your risk of hypertension, diabetes, and high cholesterol
• Poor nutrition, as diets high in saturated fats and added salt (and low in nutrient-dense foods like fruits and vegetables), increase stroke risk
• Excessive alcohol consumption increases blood pressure and increases the risk of atrial fibrillation and stroke
• Taking certain medications, such as birth control pills or hormone replacement therapy (especially when you also smoke)
• High blood sugar levels, which contributes to inflammation and stress on the body as well as damage to the blood vessels
• Having high C-reactive protein (CRP), which is a nonspecific biomarker of inflammation with elevated levels indicating inflammation somewhere in your body 

Non-modifiable risk factors for stroke are things you can’t change: 

• Having had a previous stroke
• Being male
• Aging, as the risk for stroke increases significantly over age 55
• Being of a certain ethnic group, such as African Americans, Hispanics, and Asian/Pacific Islanders
• Genetics

I realize that was a long list. Rather than getting overwhelmed by it, consider how many of the risk factors above apply to you and choose a few you can target. If you control your risk factors to the best of your ability, you can reduce your risk of having a stroke — no matter your age, gender, genetics, or ethnicity. 

Stroke Prevention

Understanding why a stroke occurs is the first step in preventing a first and a second. After an event occurs, your cardiologist may perform a variety of tests to determine the underlying cause of the stroke. This will help guide your treatment plan. 

A well-rounded plan should include visits to a registered dietitian who specializes in heart disease, who will ensure you are eating the foods that prevent stroke, and meet your nutritional needs for optimal blood vessel and heart health.

While strokes affect brain health, the problem is a cardiac issue that starts within your blood vessels. About 87% of strokes are called “ischemic” attacks, which means there is a lack of blood flow to the brain. 

An ischemic stroke generally has two underlying causes: atherosclerosis and high blood pressure.  

Atherosclerosis is when fatty deposits, including cholesterol, block artery walls. If allowed to build up, these deposits can eventually block blood flow, or even burst and result in a blood clot. People with high LDL cholesterol are at increased risk of developing atherosclerosis over time.

High blood pressure, or hypertension, can cause damage to arteries, by causing little tears and cracks along the interior artery surface. Because the walls of the blood vessels are no longer smooth, cholesterol can collect along the damaged areas, contributing to the development of atherosclerosis.

Luckily, you can improve both atherosclerosis and high blood pressure with diet and lifestyle changes to lower your risk of stroke. 

Know Your Numbers: Blood Pressure and Cholesterol

Knowing your blood pressure and cholesterol levels and understanding what they mean is important for improving your health and lowering your risk of stroke. If you haven’t been tested recently, ask your doctor to check your levels and give you a written report to share with the rest of your healthcare team.

Blood Pressure (BP): Ideal blood pressure numbers are less than 120 for systolic (the upper number) and less than 80 for diastolic (the bottom number). Numbers chronically above these put you at risk for damage to your blood vessels. The higher the numbers are, the higher your risk.

Controlling Cholesterol: Cholesterol is a waxy substance used to make cell walls, hormones, and other important things like vitamin D. Humans can make cholesterol in the liver from the foods we eat.

Our bodies transport cholesterol in our blood by using protein transporters called lipoproteins. When our bodies have too much of a certain kind of lipoprotein called low-density lipoprotein (LDL) it will deposit excess cholesterol in less than ideal places, like along our cell walls. In contrast, high-density lipoproteins (HDL), sometimes called “healthy cholesterol” transports cholesterol to the liver where it can be broken down. However, some research now suggests that LDL is more of an independent risk factor for heart health and that HDL may not tell us as much as we once thought. 

Ideally, you want your LDL to be low and your HDL to be high (but not too high). Optimal cholesterol should be maintained within these parameters:

• Total cholesterol below 200 mg/dL
• LDL below 100 mg/dL
• HDL greater than 40 mg/dL
• Triglycerides (a fat we use for energy) less than 150 mg/dL

However, in those who are at higher risk, these values may be stricter. For instance, goals may be having an LDL below 70mg/dL and triglycerides below 100mg/dL. Additionally, having an HDL above 80mg/dl can make it dysfunctional, so there are instances in which these biomarkers are kept within a tighter range. 

If your heart health biomarkers are outside the ranges above, including if your blood pressure is elevated (over 120/80 mmHg), it’s crucial to get medical guidance and support. Speak with your doctor and cardiac dietitian for a plan to improve your heart health.

For more of an advanced look at your LDL cholesterol, read my other blog post, “What a High LDL Particle Number Means for Developing Atherosclerosis: What a Top Cardiac Dietitian Wants You to Know”. 

To evaluate your modifiable risk factors for stroke and help protect yourself against a first or second stroke, 1:1 nutrition counseling can help. Read more about what I offer here and consider booking a discovery call to learn more. 

References

1. Stroke Facts. Centers for Disease Control and Prevention. Reviewed 4 May 2023. Available from: https://www.cdc.gov/stroke/facts.htm 
2. Chen L, et al. The role of high-sensitivity C-reactive protein serum levels in the prognosis for patients with stroke: a meta-analysis. Neurological Biomarkers, 2023. Available from: https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2023.1199814/full 
3. Treat and Recover from Stroke. Centers for Disease Control and Prevention. Reviewed 4 May 2023. Available from: https://www.cdc.gov/stroke/treatments.htm 
4. Ischemic Stroke (Clots). American Heart Association. Available from: https://www.stroke.org/en/about-stroke/types-of-stroke/ischemic-stroke-clots 
5. What Is Atherosclerosis? National Heart Lung and Blood Institute. Updated 24 March 2022. Available from: https://www.nhlbi.nih.gov/health/atherosclerosis 
6. Why High Blood Pressure is a “Silent Killer. Heart.org. Reviewed 31 May 2023. Available from: https://www.heart.org/en/health-topics/high-blood-pressure/why-high-blood-pressure-is-a-silent-killer 
7. Warning Signs. The Stroke Foundation. Available from: https://thestrokefoundation.org/home/stroke-facts/warning-signs/?gad_source=1&gclid=CjwKCAjwuJ2xBhA3EiwAMVjkVJfp2ZOqSfKhPIzG9NXNx01p–XPClXxebdpBZLoMfrwiacGmWF6DRoCXt0QAvD_BwE 
8. Hui C, Tadi P, Patti L. Ischemic Stroke. [Updated 2022 Jun 2]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK499997/ 
9. Unnithan AKA, M Das J, Mehta P. Hemorrhagic Stroke. In: StatPearls. Treasure Island (FL): StatPearls Publishing; May 8, 2023.
10. Boehme AK, Esenwa C, Elkind MS. Stroke Risk Factors, Genetics, and Prevention. Circ Res. 2017;120(3):472-495. doi:10.1161/CIRCRESAHA.116.308398
11. Cholesterol Levels: What You Need to Know. Medline Plus. Available from: https://medlineplus.gov/cholesterollevelswhatyouneedtoknow.html