Life expectancy in the U.S. decreased to 77.0 in 2020 from 78.8 years in 2019. In 2021, it fell even lower to 76. Though some diseases are more prevalent as Americans get older, it is important to be mindful of one's health at any age.

According to the Centers for Disease Control and Prevention (CDC), nine of the ten leading causes of death in 2020 were the same as in the previous year. This means knowing the most prevalent causes may help people take preventive steps to avoid serious illness and untimely death.

Begin caring for your health by knowing the top 10 leading causes of death in the U.S.

Heart Disease

According to the CDC, heart disease was at the top of all causes of death in the U.S. in 2020, across races and ethnic backgrounds. It resulted in almost 700,000 deaths in the country that year – equivalent to one in every five deaths. This mortality rate has cost the country about $229 billion annually for health care services, medicines, and lost productivity from 2017 to 2018.

Coronary heart disease (CHD), the most common type of heart disease, resulted in the death of almost 400,000 people in the country in 2020. More than 20 million adults, or 7.2% of the population, aged 20 and older, reportedly had CHD.

One person had a heart attack every 40 seconds in the country. Two in ten deaths from CHD were in adults less than 65 years of age.

Cancer

America's second leading cause of death was responsible for one of every four deaths in the U.S. in 2019, according to the latest data by the CDC. Over 600,000 U.S. residents died from cancer in 2020. For every 100,000 people, almost 500 new cancer cases got reported, and 146 died of cancer. In 2019, more than 1.7M new cancer cases got reported.

Of the top 10 cancers by rates of new cancer cases across all races and ethnicities, female breast cancer was at the top, with 264,121 new cases reported in 2019. It was followed by prostate cancer (224,733 new cases), lung and bronchus (221,097 new cases), and colon and rectum (142,462). In terms of cancers by rates of cancer deaths, lung and bronchus cancer resulted in the deaths of 34 people every 100,000 across all races and ethnicities.

COVID-19

COVID-19 was the third leading cause of death in the U.S. It resulted in 350,831 deaths in 2020. The highest seven-day average of reported deaths of all time was almost 4,000, according to a graph by the New York Times.

As of Sept. 8, 2022, the number of reported cases per day decreased significantly, with a national average of 90,000 cases reported per day.

The U.S. is continuously monitoring the emergence of new variants of the disease. The omicron variant could spread more easily than the delta variant and other previously known variants, according to the CDC. Data also suggested that reinfection is possible for those who have had the omicron variant, even if they have recovered from COVID-19. COVID vaccines are available to help prevent severe illness, hospitalization and even death. The CDC also mentioned that some monoclonal antiviral treatments are effective against the omicron variant.

Accidents (Unintentional Injuries)

The prevalence of accidents and unintentional injuries resulting in death was high in the U.S., responsible for over 200,000 deaths. This was equivalent to 61 deaths every 100,000. Of which, 13 deaths every 100,000 were due to unintentional falls. Another 13 of every 100,000 deaths, or 40,698 deaths, were due to motor vehicle traffic deaths. Unintentional poisoning also resulted in 87,404 deaths in the U.S.

There were almost 25M physical office visits for unintentional injuries, and almost 98M emergency department visits for unintentional injuries.

Stroke (Cerebrovascular Diseases)

The CDC's 2020 data revealed that one in six deaths from cardiovascular disease was due to stroke. This was equivalent to one person having a stroke every 40 seconds. Every 3.5 minutes, there was a death attributed to a stroke.

The majority of strokes in the U.S. every year are first or new strokes. Almost 90% of all strokes are considered ischemic strokes, where blood flow to the brain gets blocked. The U.S. lost nearly $53 billion between 2017 and 2018 to costs associated with health care services, medicines, and lost productivity.

Since one in every three American adults having at least one of the leading causes of stroke, such as high cholesterol, high blood pressure, smoking, obesity, and diabetes, Americans are at risk for stroke, according to the CDC.

In strokes that do not result in death, it may also be a leading cause of long-term disability. The risk of having a stroke varies with race and ethnicity. Though the risk for stroke increases as a person ages, strokes may occur at any age.

Chronic Lower Respiratory Diseases (COPD)

According to the National Health Interview Survey of 2019-2020, 5% of adults were diagnosed with COPD, emphysema, or chronic bronchitis. The sixth leading cause of death in the U.S. resulted in 46.3 deaths per 100,000. Bronchitis (chronic and unspecified deaths) resulted in 457 deaths, while emphysema resulted in 7,425 deaths. Other chronic lower respiratory diseases (excluding asthma) resulted in almost 48 deaths in every 100,000 people.

Alzheimer's Disease

One of the leading causes of death in America is Alzheimer's disease, the most common type of dementia. This progressive disease begins with mild memory loss and may lead to the loss of the ability to respond to the environment and carry on a conversation.

In 2020, almost 6M Americans were reported to have the disease. The risk of Alzheimer's increases with age. Alzheimer's in younger people exists, though uncommon. Scientists are still in the process of studying the full extent of Alzheimer's. Experts believe that genetics may play a role in disease development. However, a healthy lifestyle may reduce one's risk for the disease.

Warning signs include memory loss that disrupts daily life, trouble handling money and remembering to pay the bills, difficulty completing familiar tasks at home, poor judgment, misplacing familiar items, inability to retrace one's steps to find a missing item, and changes in behavior, mood or personality.

Diabetes

This chronic health condition affects how the body turns food into energy. A person diagnosed with diabetes cannot produce enough insulin in the body or use it efficiently. The production of insulin is the body's response to blood sugar levels going up. Without enough insulin, too much sugar remains in the bloodstream, resulting in heart or kidney disease or vision loss.

Over 37M American adults have diabetes, with a fifth of them unaware of their health condition. There are three types of diabetes – type 1, type 2 and gestational diabetes. About 95% of people with diabetes have type 2 diabetes — developing over many years. Diabetes is behind 102,188 deaths in the U.S., and it is currently incurable. The CDC recommended losing weight, eating healthy, and living an active lifestyle to manage diabetes.

Influenza And Pneumonia

The eighth leading causes of death in the U.S. are influenza and pneumonia, accounting for 53,544 deaths. Influenza is a highly contagious infection caused by a virus, while pneumonia is an inflammation or infection of the lungs. Though most cases of influenza, also known as the flu, never lead to pneumonia, those that do tend to be deadly, according to the American Lung Association. Flu is one of the most severe illnesses in winter.

Around 6,062 deaths due to influenza and pneumonia were reported in California in 2020; at the same time, 4,756 deaths were reported in New York.

There are protective vaccines against flu and pneumonia. However, no flu vaccine is 100% effective since flu strains change every year.

Nephritis, Nephrotic Syndrome And Nephrosis

The National Kidney Foundation defines nephrotic syndrome or nephrosis as the condition when the kidneys start losing large amounts of protein in the urine. A worsening condition results in salt and fluid build-up in the body, leading to swelling or edema, high blood pressure and higher cholesterol levels. This condition may arise from kidney diseases or other diseases such as diabetes or lupus. Nephritis or nephrotic syndrome may also be referred to as glomerulonephritis, a group of diseases injuring the glomeruli – the part of the kidney that filters blood.

According to the National Health Interview Survey of 2018, 6M adults aged 19 and above have been diagnosed with kidney disease. The number of deaths attributed to nephritis, nephrotic syndrome and nephrosis is 52,547, translating to about 16 Americans per 100,000 population.

In 2010, nephritis, nephrotic syndrome and nephrosis accounted for 16.3 deaths per 100,000 population, the highest since 1999, according to Statista. In 1999, it accounted for 12.7 deaths per 100,000.