Global life expectancy has risen 5.5 years since 2000. This means that a child born in 2016 could expect to live to be 72 years old. This is up from the 66.5 years a child born in 2000 could have expected if one used World Health Statistics reports. There are many government policies that have contributed to this, though recent studies suggest certain policies aren’t as effective as first thought. Yet we are starting to determine what factors have the greatest impact on overall life expectancy and global health. Let’s learn why access to early healthcare, sanitation, and good air quality are directly related to life expectancy.

The Impact of Sanitation on Life Expectancy

Water, sanitation, and hygiene or WASH have a direct impact on early childhood survival rates. Waterborne illnesses spread through poor sanitation have historically killed a fair percentage of children before they reached the age of five. Furthermore, repeated bouts of diarrhoea contribute to malnutrition and stunted growth. Modern studies to get more accurate data on the impact of sanitation on life expectancy and long-term health are often insufficient since they don’t follow people long enough to get a full picture. They are typically skewed toward the rural population and have poor compliance.

A recent study sought to overcome these problems by combining data from the Demographic Health Surveys of 59 countries. It found that improved water access didn’t change survival outcomes for the poor very much, although greater access to sanitation did. For each one percentage point increase in sanitation coverage, under-child 5 mortality fell roughly 0.3 to 0.4 per 1000 births. All of this means that sanitation improvements only account for roughly ten percent of the decline in global child mortality rates from 1990 to 2015. However, piped water into the home was associated with a reduction in stunting or wasting. This shows that they have lower rates of serious malnutrition. For example, greater toilet use in a community is correlated with a lower rate of anaemia since there is a reduced spread of intestinal worms.

The Impact of Air Quality on Life Expectancy

There are an estimated three million deaths a year due to outdoor air pollution. Another 4.3 million deaths each year are attributed to air pollution from cooking fuel. To put this in perspective, more than twice as many people die every year from smog and other outdoor pollution than die in car accidents every year. Three million more people die from emphysema and respiratory infections due to cooking indoors over wood stoves than are murdered or commit suicide in a given year. This is why poor air quality is having a major impact on global life expectancy.

A Sacred Heart University scholar calculated that every microgram per cubic meter of particulate matter in the air we’re exposed to reduces our life expectancy by 0.04 years. The matter is more pressing in certain parts of the world. For example, half a million more premature deaths are occurring each year in China from air pollution than water pollution. Globally, particulate air pollution reduces life expectancy by nearly two years. For comparison, this means that the effect of air pollution on life expectancy now exceeds that of tuberculosis, HIV, and even war according to a study by the Energy Policy Institute with the University of Chicago.

The Impact of Early Healthcare on Life Expectancy

Life expectancy has jumped up globally due to advances in healthcare in sub-Saharan Africa. This includes progress against malaria, measles, and HIV/AIDS. Thanks to improvements in malaria control, access to HIV treatment, nutrition and overall child survival, life expectancy in Africa rose 9.4 years to roughly 60 years.

However, there is more work to be done. The challenge is learning what the most cost-effective solutions are. We need to know because there remains a significant gap in life expectancies between developing and developed nations. In low-income nations, people die on average 18 years sooner than those in high-income nations. The gap between the richest and poorest is even greater. In the world’s 30 highest income countries, life expectancy is more than 80 years, while infants born in the 22 poorest countries have life expectancies of under 60. That’s a gap of more than twenty years. There are things the developed world can do to improve their numbers. However, both the developed and the developing world must prioritise spending to save as many lives as possible.

Research conducted by shows that the NHS would need £12 billion more to maintain current provisions and £20 billion to improve services. This comes out to an additional £150 per household to maintain the level of service and £340 per year to improve it and modernise it. While this may sound steep, it is still less than the United States spends per capita.  In 2018, Theresa May proposed increasing NHS spending by £20 billion or roughly 3.4 percent per year every year through 2024. Boris Johnson proposed a mere £1.8 billion funding boost for buildings.

We can also compare healthcare spending as a percentage of the average person’s income. In the U.S., they spend roughly five percent of their annual salary on out of pocket and voluntary healthcare. A disproportionate amount of that money goes to pay for top-selling prescriptions like rheumatoid arthritis injections and insulin.

In the U.K., these modernisation proposals would result in the average person paying roughly 4.4 percent of their income on healthcare. They’re currently spending about 3.5 percent. Part of this is due to the more affordable and accessible prescription drugs patients receive. Note that this is a relative bargain compared to what the Swiss face. They are spending roughly 8.5 percent of their income on healthcare per year according to OECD data. The next runner up is Portugal; the average person there spends nearly seven percent of their income on healthcare costs.

Access to prescription drugs saves lives. For example, patients in the U.S. rationing insulin are at risk of high and low blood sugar levels that threaten their lives. Access to drugs that manage high blood pressure, blood sugar, and endocrine disorders reduce the risk of serious complications and add years to patients’ lives.

Greater access to preventative healthcare could close the gender gap in life expectancy, too. Women live roughly five years longer than men because they are better at utilising available healthcare. For example, women are more likely to take HIV tests and seek retroviral therapies. This same trend is seen in female tuberculosis patients.


We now have the hard data showing that advances in preventive healthcare, improved air quality, and sanitation will save millions of lives every year. They will also add years to the life expectancy in the poorest parts of the world while improving overall quality of life.