Global life expectancy is set to increase by almost five years by 2050, according to a new forecast.

The average lifespan is predicted to rise from 73.6 years in 2022 to 78.1 years in 2050.

But there are significant differences between men and women.

The average life expectancy for women will rise from 76.2 years in 2022 to 80.5 years in 2050, and for men from 71.1 years to 76 years, according to the Global Burden of Disease Study (GBD) 2021.

However, people are also expected to spend more years in poor health, with a smaller increase in the time people will live well. The data shows global healthy life expectancy will increase from 64.8 years in 2022 to 67.4 years in 2050 – an increase of only 2.6 years.

It predicts the continuing shift from non-communicable diseases (NCDs) – such as cardiovascular diseases, cancer, and diabetes – and exposure to NCD-associated risk factors – such as obesity, high blood pressure, unhealthy diet, and smoking – will have the greatest effect on the impact of health issues for the next generation.

The five leading causes of disease in 2050 are predicted to be ischemic heart disease, stroke, diabetes, chronic obstructive pulmonary disease and neonatal disorders.

In the US, average life expectancy for women will rise from 80 years from 2021 to 82.4 in 2050, and from 74.3 years to 78.4 years for men.

In the UK, it will rise from 82.4 years to 85 in 2050, and from 78.2 years to 82.1 for men.

In the UAE, it will rise from 71.5 years to 73.2 for women, and from 77.5 years to 81.6 for men.

In Saudi Arabia, it will rise from 75.1 years to 78.3 for women, and from 71.8 years to 75.2 for men.

In Bahrain, it will rise from 75.1 years to 80 for women, and from 72.2 years to 79 for men.

In Oman, it will rise from 76.3 years to 82.6 for women, and from 70.5 years to 77.6 for men.

It comes as public health measures have prevented, and improved survival rates from, cardiovascular diseases, Covid-19, and a range of communicable (diseases that spread from one person to another), maternal, neonatal, and nutritional diseases (CMNNs), according to the report.

Dr Chris Murray, chairman of health metrics sciences at the University of Washington in the US, and director of the Institute for Health Metrics and Evaluation (IHME), said: “In addition to an increase in life expectancy overall, we have found that the disparity in life expectancy across geographies will lessen.

“This is an indicator that while health inequalities between the highest and lowest income regions will remain, the gaps are shrinking, with the biggest increases anticipated in sub-Saharan Africa.”

Although global life expectancy is forecast to increase from 2022 to 2050, the improvement is at a slower pace than in the three decades preceding the Covid-19 pandemic, the study found.

The findings build upon the results of the GBD 2021 risk factors study, also released on Thursday in The Lancet.

The research found that the total number of years lost due to poor health, and early death attributable to metabolic risk factors such as high blood pressure, high blood sugar, and high BMI, has increased by almost 50 per cent (49.4 per cent) since 2000.

The analysis based its estimates on 88 risk factors and their associated health outcomes for 204 countries and territories from 1990 to 2021.

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Particulate matter air pollution, smoking, and low birthweight and short gestation were also among the largest contributors to lost years of healthy life due to poor health and early death in 2021, with considerable variation across ages, sexes and locations.

The study found that substantial progress was made between 2000 and 2021 in reducing disease attributable to risk factors linked to maternal and child health, unsafe water, sanitation, and handwashing, as well as household air pollution from cooking with solid fuels.

Dr Emmanuela Gakidou, professor of health metrics sciences at the IHME, said: “Risk factors that currently lead to ill health, such as obesity and other components of metabolic syndrome, exposure to ambient particulate matter air pollution, and tobacco use, must be addressed via a combination of global health policy efforts and exposure reduction to mitigate health risks and improve population health.”

Dr Murray said: “There is immense opportunity ahead for us to influence the future of global health by getting ahead of these rising metabolic and dietary risk factors, particularly those related to behavioural and lifestyle factors like high blood sugar, high body mass index, and high blood pressure.”