Preventable causes of death are causes of death related to risk factors which could have been avoided. The World Health Organization has traditionally classified death according to the primary type of disease or injury. However, causes of death may also be classified in terms of preventable risk factors—such as smoking, unhealthy diet, unprotected sexual behavior (STIs), and reckless driving—which contribute to a number of different diseases. Such risk factors are usually not recorded directly on death certificates, although they are acknowledged in medical reports.

Worldwide It is estimated that of the roughly 150,000 people who die each day across the globe, about two thirds—100,000 per day—die of age-related causes. In industrialized nations the proportion is much higher, reaching 90 percent. Thus, albeit indirectly, biological aging (senescence) is by far the leading cause of death. Whether senescence as a biological process itself can be slowed, halted, or even reversed is a subject of current scientific speculation and research.

2001 figures Risk factors associated with the leading causes of preventable death worldwide as of the year 2001, according to researchers working with the Disease Control Priorities Network (DCPN):

Cause Number of deaths resulting(millions per year)Hypertension 7.8Smoking tobacco 5.4Alcohol use disorder 3.8Sexually transmitted infections 3.0Poor diet 2.8Overweight and obesity 2.5Physical inactivity 2.0Malnutrition 1.9Indoor air pollution from solid fuels 1.8Unsafe water and poor sanitation 1.6

By contrast, the World Health Organization (WHO)'s 2008 statistics list only causes of death, and not the underlying risk factors.

In 2001, on average 29,000 children died of preventable causes each day (that is, about 20 deaths per minute). The authors provide the context:

Western societies In 2017, The Lancet published a large study by Swiss epidemiologist Silvia Stringhini and her collaborators, analysing the impact of the most important causes of preventable death in Western societies. They estimated the number of years of life lost for each risk factor at the individual level and its contribution to preventable death at the societal level (PAF = Population Attributable Fraction).

The multicohort study and meta-analysis used individual-level data from 48 independent prospective cohort studies with information on socioeconomic status, high alcohol consumption, physical inactivity, current smoking, hypertension, diabetes and obesity, and mortality, for a total population of 1,751,479 from seven high-income WHO member countries.

A limitation of many studies of health risk factors is confounding bias: many risk factors are interrelated and cluster together in high-risk populations. For example, low physical activity and obesity go hand in hand. People who are physically inactive tend to gain weight, and people who are severely obese have difficulty exercising. The unique advantage of the huge amount of individual data in the Stringhini study is that it allows (estimation of) the relative contribution of each separate risk factor.

The following table shows that, at an individual level, smoking is the single greatest risk of avoidable death, followed by diabetes and high alcohol consumption. At the population level, diabetes and high alcohol consumption have a low prevalence. Physical inactivity, smoking and low socioeconomic status (SES) are then the top three preventable causes of early death. Smoking, physical inactivity and low SES account for almost two thirds of all avoidable deaths.

+Risk factors for avoidable death: Pooled hazard ratios, life years lost and population attributable fraction (PAF) for six WHO-defined health risks and socioeconomic status (SES)(Meta-analysis data of prospective cohort studies, from Stringhini et al., Lancet 2017). Risk factorReference Hazard ratio Life years lostbetween ages40 and 85 Prevalence Percentage ofdeaths whichwere premature(PAF)Physical inactivity1.592.3043.7%24.5%Current smokingNever smoking2.084.6023.3%24.0%Low Socio-Economic StatusHigh SES1.382.0635.4%17.2%Diabetes1.793.999.0%6.5%High alcoholModerate alcohol intake1.620.486.8%3.7%Hypertension1.291.5434.0%8.8%ObesityNormal BMI1.110.6820.9%Small A puzzling finding is the small contribution of obesity as a cause of avoidable premature death. There are two reasons why obesity is not an important independent risk factor, as is often assumed.

Being overweight is a risk for early death without correcting for confounding risk factors. Overweight is usually measured by the body mass index (BMI = kg/m2), which is much easier to measure than physical activity. Most studies only measured BMI, not physical activity, and did not correct for confounding. A major pitfall in many studies of weight and health is that "normal" and "healthy" are often confused. The WHO definition of "normal" adult BMI (between 18.5 and 24.9 kg/m2) is based on a normal weight and height distribution of US citizens in the 1960s, not on the associated risk of death in 2023. A meta-analysis of the association between BMI and mortality in 230 cohort studies with 3.74 million deaths among 30.3 million participants found that the risk of death in adults is not increased between 23 and 30 kg/m2 (see Figure 2). An adult BMI of 18.5 kg/m2, considered 'normal' by WHO criteria, is associated with a 30% increase in all-cause mortality. However, this is a measure of correlation, not causation, so it does not disprove previously held notions of the relationship between health and weight.

United States

The three risk factors most commonly leading to preventable death in the population of the United States are smoking, high blood pressure, and being overweight.

Risk factors for preventable deaths are also common to many American cults and religious movements – ranging from masterminded mass tragedies such as the Heaven's Gate ritual suicides, to the outright rejection of life-sustaining or life-saving medical treatment by groups such as Christian Science and Jehovah's Witnesses; the latter religion's former stance against blood transfusions is credited with the medically preventable deaths of 50,000 of its members globally. https://pubmed.ncbi.nlm.nih.gov/8430707/ https://www.jw.org/en/library/books/2025-Service-Year-Report-of-Jehovahs-Witnesses-Worldwide/2025-Grand-Totals/

Accidental death

Annual number of deaths and causes

+Avoidable causes and numbers of death per yearCause of death Number ofdeaths Percent of total Notes Smoking tobacco 435,000 18.1% Obesity 111,900 4.6% There was considerable debate about the differences in the numbers of obesity-related diseases. The value here reflects the death rate for obesity that has been found to be the most accurate of the debated values. Note, however, that being overweight but not obese was associated with fewer deaths (not more deaths) relative to being normal weight. Alcohol 85,000 3.5% Infectious diseases 75,000 3.1% Toxic agents including toxins, particulates and radon 55,000 2.3% Traffic collisions 43,000 1.8% Preventable colorectal cancers 41,400 1.7% Colorectal cancer (bowel cancer, colon cancer) caused 51,783 deaths in the US in 2011. About 80 percent of colorectal cancers begin as benign growths, commonly called polyps, which can be easily detected and removed during a colonoscopy. Accordingly, the tabulated figure assumes that 80 percent of the fatal cancers could have been prevented. Firearms deaths 31,940 1.3% Suicide: 19,766; homicide: 11,101; accidents: 852; unknown: 822.Sexually transmitted infections 20,000 0.8% Substance use disorder 17,000 0.7%

Among children worldwide Various injuries are the leading cause of death in children 9–17 years of age. In 2008, the top five worldwide unintentional injuries in children were as follows:

+Avoidable numbers of death among children Cause Deathsper year Traffic collision260,000 Drowning175,000 Viruses96,000 Falls47,000 Toxins45,000

See also

Health effects of alcohol Short-term effects of alcohol consumption Long-term effects of alcohol consumption Jehovah's Witnesses and blood transfusions

List of causes of death by rate Particulates

Religion and health § Modern developments

References