One in four deaths caused by human activity

The World Health Organisation estimates that 1 in 4 deaths is a result of diseases caused by human activity, including pollution & chemical exposures and climate change. 

Top 10 causes of death

Over half (54 percent) of the 60 million annual deaths worldwide can be attributed to 10 causes. 

1: Ischaemic heart disease (8.8 percent)

Ischemic heart disease is a range of heart diseases caused by decreased oxygen supply to the heart most often due to damage or narrowing of the arteries. An unhealthy lifestyle is a major risk factor (including smoking, lack of exercise, obesity, a poor diet, excessive alcohol intake).

2: Stroke (6.2 percent)

A stroke is when poor blood flow to the brain results in the dying of brain cells due to lack of oxygen and nutrients. This causes the brain to not function properly. There are two main types of stroke: lack of blood flow and bleeding. The most important risk factors include high blood pressure, cigarette smoking, excessive drinking of alcohol, lack of physical activity, obesity, and an unhealthy diet.

3: Lower respiratory infections (3.2 percent)

Lower respiratory infections is a range of conditions that include pneumonia (infection of the lungs) as well as infections in the airways such as acute bronchitis and influenza. 

4: Chronic obstructive pulmonary disease (3.2 percent)

Chronic obstructive pulmonary disease (COPD) is an obstructive lung disease characterized by long-term breathing problems that typically worsens over time. Tobacco smoking is the main cause of COPD but other factors such as air pollution also play a role. Most cases of COPD can be prevented by reducing exposure to risk factors but no cure is known. More than 90 percent of  of deaths from COPD occur in the developing world. 

5: Lung cancer (including trachea and bronchus cancer) (1.7 percent)

Lung cancer is characterized by uncontrolled cell growth in tissues of the lungs, trachea or bronchi creating a malignant tumor. The vast majority (85 percent) of cases of lung cancer are due to long-term tobacco smoking but factors such as air pollution also play a role. Avoidance of these factors is the most important way to reduce the risk of lung cancer.

6: Diabetes (1.6 percent)

Diabetes refers to a group of metabolic disorders characterized by high blood sugar levels over a prolonged period of time. 

Type 1 diabetes results from the body’s failure to produce enough insulin. Insulin is a hormone made by the pancreas that allows us to transform sugar into energy. Type 1 diabetes is believed to be caused by a combination of genetic and environmental factors but the exact cause is unknown.

Type 2 diabetes starts as insulin resistance meaning that the human cells fail to respond to insulin properly. The most common cause is excessive body weight and insufficient exercise. Prevention and treatment includes a healthy diet, physical exercise, a normal body weight, and no smoking.

Finally, gestational diabetes is when a woman without diabetes develops high blood sugar levels during pregnancy. 

Of the different types of diabetes, type 2 makes up about 90 percent, type 1 roughly 5-10 percent and gestational diabetes around 3-9 percent.

7: Dementia including Alzheimer's (1.5 percent)

Dementia is a broad category of brain diseases that cause a long-term decrease in brain functioning including the memory and other cognitive abilities and motor skills. The most common type of dementia is Alzheimer's disease which represents up to 70 percent of cases. The cause of Alzheimer's and other dementia diseases is poorly understood. About 70 percent of the risk of Alzheimer’s is believed to be genetic. There is no known cure for dementia. 

8: Diarrhea / diarrhoeal diseases (1,4 percent)

Diarrhea is defined as having at least three bowel movements within 24 hours that are sufficiently liquid to take the shape of the container in which they are placed. The most severe threat posed by diarrhoea is dehydration.

Every single minute a child under five dies from diarrhea

The most common cause of Diarrhea is an infection of the intestines due to either a virus, bacteria, or a parasite. Each year diarrhoea kills around 525 000 children under five making it the second leading cause of child death (the lead cause being Pneumonia and other acute respiratory infections).

Diarrhea is both preventable and treatable

A main source of diarrhea is contaminated water. Children who die from diarrhoea often suffer from underlying malnutrition, which makes them more vulnerable to diarrhoea. Many cases of diarrhea can be avoided through safe drinking-water and good sanitation and hygiene. Treatment include rehydration and Nutrient-rich foods.

9: Tuberculosis (1,4 percent) 

Tuberculosis (TB) is an infectious disease caused by bacteria that generally affects the lungs but can also affect other parts of the body. More than 95 percent of deaths from TB occur in developing countries. In about 90 percent of infections there are no symptoms. About 10 percent result in active disease of which, if not treated, about 50 percent will die. Roughly one-third of the world's population is infected with TB while new infections occur in about 1 percent of the population each year.

TB is a leading killer of people with HIV. In 2016, 40 percent of HIV-related deaths were due to TB.

10: Road injury / traffic accident (1,3 percent)

Traffic accidents are the leading cause of death for young people between 15 and 29 years.

90 percent of fatalities occur in low- and middle-income countries, even though these countries only have about half of the world's vehicles.

The number of road fatalities per year per 100,000 inhabitants varies greatly between countries. In some (especially African) countries more than 30 people per 100,000 inhabitants are killed every year. In other countries, less than 5 people. The number of road fatalities per 100,000 vehicles varies even more from over 1000 in some countries to less than 5 in others.

Indirect causes of death

Many causes of death are affected by factors such as smoking, obesity, inactivity and pollution. Tobacco smoking, for example, has caused an estimated 100 million deaths in the 20th century.