In the United States, the top three causes of death in 2020 were heart disease, cancer, and COVID-19. Accidents and stroke round out the country’s top five causes of death that year. And the leading worldwide cause of death for 2020 was ischemic heart disease, with stroke coming in a close second.

In 2020, there were 3,383,729 deaths in the U.S. For the first time, COVID-19 was one of the leading causes of death, coming in at number three on the list. Together, these three conditions accounted for nearly 49% of the total deaths in the country.

This article focuses on the 10 biggest causes of health-related deaths in 2020 in the U.S. and worldwide. Gaining awareness of the leading causes of death and how to help prevent them may allow people to live a long, healthy life.

Read on to learn more about the 10 biggest causes of death and how to help prevent them.

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According to the Centers for Disease Control and Prevention (CDC), in 2020, the 10 leading causes of death in the U.S. accounted for 74.1% of the total deaths. Compared to 2019, nine of the top 10 causes were the same in 2020 and five causes changed position.

Cause of death Total number of deaths Percentage of total deaths
1. Heart disease 696,96220.6%
2. Cancer 602,35017.8%
3. COVID-19350,83110.4%
4. Accidents (unintentional injuries) 200,9555.9%
5. Stroke (cerebrovascular diseases)160,2644.7%
6. Chronic lower respiratory diseases152,6574.5%
7. Alzheimer’s disease 134,2424%
8. Diabetes 102,1883%
9. Influenze and pneumonia 53,5441.6%
10. Nephritis, nephrotic syndrome, and nephrosis (kidney disease)52,5471.6%

1. Heart disease

  • Deaths in 2020: 696,962
  • Percentage of total deaths: 20.6%

The leading cause of death in 2020 was heart disease, which includes several conditions that affect the heart and blood vessels. Many conditions are related to atherosclerosis, a condition that occurs due to plaque buildup in the artery walls.

Plaque buildup causes arteries to narrow and stiffen, which can impede blood flow. This may lead to blood clots, stroke, or heart attack. It can also cause angina, heart arrhythmias, and heart failure.

Prevention includes exercising regularly, eating a nutritious diet, and maintaining a moderate weight.

Learn more about heart disease.

2. Cancer

  • Deaths in 2020: 602,350
  • Percentage of total deaths: 17.8%

Cancer is a condition that occurs when atypical or old cells in the body do not die, causing the cells to continue producing new cells. This leads to an overproduction of cells, which can disrupt the regular functioning of the body. Cancer can occur anywhere in the body and spread to different areas, including the lymph nodes or body organs.

The two main types of cancer are:

  • Hematologic (blood) cancers: Cancers of the blood cells include leukemia, lymphoma, and multiple myeloma.
  • Solid tumor cancers: These cancers involve a malignant lump or growth that affects the body organs or tissues. The most common types are breast, prostate, lung, and colorectal cancers.

Causes of cancer include genes, lifestyle habits, and environmental toxins. Often, the cause is unknown.

Exercising regularly, following a nutritious diet, and avoiding extended sun exposure may help prevent cancer. Other preventative measures include limiting alcohol intake and quitting smoking.

3. COVID-19

  • Deaths in 2020: 350,831
  • Percentage of total deaths: 10.4%

In 2020, COVID-19 was a leading cause of death for the first time. A virus called SARS-CoV-2 causes COVID-19, a contagious disease that may affect the lungs, respiratory system, and other areas of the body.

SARS-CoV-2 spreads in three principal ways:

  • Inhaling air when near a person with the infection who is exhaling small droplets and particles containing the virus.
  • Small droplets and particles that carry the virus landing on the eyes, nose, or mouth, especially via splashes and sprays, including coughs and sneezes.
  • Using hands that have the virus on them to touch the eyes, nose, or mouth.

COVID-19 can cause mild-to-severe symptoms or no symptoms at all. Older adults and people with certain underlying medical conditions are more likely to become severely ill from the disease. It is also possible to develop post-COVID conditions.

Helping prevent COVID-19 involves getting vaccinated, wearing a mask, and washing hands often. People can also avoid crowded places, indoor spaces, and close contact with other individuals.

4. Accidents or unintentional injuries

  • Deaths in 2020: 200,955
  • Percentage of total deaths: 5.9%

Accidents or unintentional injuries are the fourth biggest cause of death.

The most common types of accidents are:

  • unintentional falls
  • motor vehicle traffic deaths
  • unintentional poisoning deaths

To prevent death from accidents and unintentional injuries, communities can implement and improve strategies and projects that relate to walkable communities, safe routes to school, and transportation safety.

There are certain programs that help prevent falls in older adults and focus on:

  • education
  • home safety
  • physical activity
  • medication management

5. Stroke (cerebrovascular diseases)

  • Deaths in 2020: 160,264
  • Percentage of total deaths: 4.7%

Stroke is a type of cerebrovascular disease that causes the arteries that supply blood to the brain to burst, rupture, or form a blockage due to a clot. This prevents the brain from receiving the necessary blood and oxygen, leading to the death of brain cells.

Following a healthy lifestyle helps prevent stroke. This includes eating a nutritious diet, maintaining a moderate weight, and exercising regularly. People can also quit smoking and reduce their alcohol intake.

Learn more about stroke.

6. Chronic lower respiratory diseases

  • Deaths in 2020: 152,657
  • Percentage of total deaths: 4.5%

Chronic lower respiratory diseases affect lung function, which can impede airflow and lead to shortness of breath, a chronic cough, and excessive sputum production.

Chronic lower respiratory diseases include:

  • chronic obstructive pulmonary disease
  • bronchitis
  • emphysema
  • asthma
  • pulmonary hypertension

People can prevent chronic lower respiratory diseases by quitting smoking, limiting exposure to allergens and pollution, and eating a nutritious diet.

7. Alzheimer’s disease

  • Deaths in 2020: 134,242
  • Percentage of total deaths: 4%

Dementia is a general term for the decline of memory, language, problem-solving, and additional cognitive capabilities that become severe enough to affect daily life.

The most common type of dementia is Alzheimer’s disease, a condition that affects memory, thinking, and behavior. It is a progressive disease that worsens over several years, starting with mild memory loss. People with late stage Alzheimer’s may lose the ability to carry on a conversation, respond to their environment, and control their movement.

To help prevent Alzheimer’s disease, individuals can get plenty of exercise, eat a nutritious diet, and improve their heart health. They can also engage in brain-stimulating activities, maintain strong social relationships, and get sufficient quality sleep.

Learn more about Alzheimer’s disease.

8. Diabetes

  • Deaths in 2020: 102,188
  • Percentage of total deaths: 3%

Diabetes is a chronic condition that occurs when the body cannot produce or effectively use insulin, a hormone that helps control blood sugar levels.

People with type 1 diabetes require daily insulin injections because they do not make insulin. Currently, there is no way to prevent type 1 diabetes.

Individuals with type 2 diabetes cannot use insulin effectively and often require medications to manage blood glucose levels. Prevention and treatment involve eating a suitable diet and getting more exercise.

Learn more about diabetes.

9. Influenza and pneumonia

  • Deaths in 2020: 53,544
  • Percentage of total deaths: 1.6%

Influenza is a viral respiratory infection that affects the nose, throat, and lungs. It is a common cause of viral pneumonia, which can also be bacterial or fungal. Pneumonia causes lung inflammation, which leads to breathing difficulties.

To help prevent influenza and pneumonia, people can quit smoking, reduce their alcohol intake, and avoid exposure to chemicals, pollutants, or toxic fumes.

Learn more about pneumonia.

10. Nephritis, nephrotic syndrome, and nephrosis (kidney disease)

  • Deaths in 2020: 52,547
  • Percentage of total deaths: 1.6%

Chronic kidney disease includes conditions such as nephritis, nephrotic syndrome, and nephrosis. These conditions harm the kidneys, which results in reduced function and waste buildup. It can cause complications such as high blood pressure, anemia, and reduced bone strength, while further issues with nutritional health and nerve damage are also possible.

Preventing these conditions includes maintaining a moderate weight and blood pressure, exercising, and eating a low sodium diet. People should also avoid smoking and drinking alcohol.

Learn more about nephritis.

According to data from the World Health Organization (WHO), these were the leading causes of death worldwide in 2019:

Cause of deathDeaths in 2019
Ischemic heart disease8.9 million
Stroke6.2 million
Chronic obstructive pulmonary disease3.2 million
Lower respiratory infections2.6 million
Neonatal conditions2 million
Tracheas, bronchus, and lung cancers1.8 million
Alzheimer’s disease and other dementias1.6 million
Diarrheal diseases1.5 million
Diabetes mellitus1.5 million
Kidney diseases1.3 million

However, these data do not include COVID-19, as the death statistics available at the end of 2020 actually relate to 2019. However, the WHO then estimated COVID to have caused more than 1.5 million deaths worldwide in 2020. This would have tied it with diarrheal diseases and diabetes mellitus, which were seventh on the list of top causes of worldwide deaths, assuming those figures stay more or less the same in the next report.

The 10 leading causes of death in the U.S accounted for nearly 75% of the total deaths. People can learn more about the most common causes of death and take steps to help prevent their onset.

Some common preventive measures include exercising regularly, eating a nutritious diet, and getting plenty of quality sleep, as many of the top causes of death relate to heart health.

Individuals should also reduce their exposure to environmental toxins and avoid potentially health-damaging substances such as alcohol and tobacco products.