IMPROVEMENT in the provision of health services, an increase in the consumption of healthy foodstuffs (balanced diet), personal hygiene and keeping an active lifestyle for optimal health and weight have contributed to improvement in global life expectancy, which has reached 73.3 years in 2024.

This is an increase of 8.4 years since 1995. In 2054, global life expectancy is projected to reach 77.4 years, according to the UN Department of Economic and Social Affairs (UNDESA)’s World Population Prospects 2024.

This has impacted the world’s population “expected to continue growing over the coming 50 or 60 years, reaching a peak of about 10.3 billion people in the mid-2080s, up from 8.2 billion in 2024. After peaking, the global population is projected to start declining gradually, falling to 10.2 billion people by the end of the century (by 2100),” says UNDESA. In 2050, the world’s population is projected to reach 9.7 billion people.

On the other hand, in 2024, the global fertility rate stands at 2.25 live births per woman, down from 3.31 births in 1990. “More than half of all countries and areas globally have fertility below the replacement level of 2.1 live births per woman. This is the level required for a population to maintain a constant size in the long run (without migration), with each generation being followed by another of roughly equal size,” says UNDESA.

The report suggests that by the late 2030s, half of the women in countries with populations that have already peaked will be too old to have children by natural means. “Because the share of women in the reproductive age range (roughly, between 15 and 49 years) is projected to decline rapidly in such countries, the impact on population size of policies aimed at raising fertility levels is likely to diminish over time,” it says.

China, Italy, the Republic of Korea and Spain, are among the 24 countries reported to experience “ultra-low” fertility, with fewer than 1.4 live births per woman over a lifetime. The report says a return to 2.1 births per woman within the next 30 years is highly unlikely (0.1 per cent) in the 24 countries with “ultra-low fertility” in 2024 that have already peaked.

In Tanzania, life expectancy is at 66.8 years in 2024 an increase of 0.13 years from life expectancy of 66.67 years in 2023. Improvement in life expectancy in the country has been contributed by improved healthcare and healthy living awareness campaigns (UNDP, 2024).

This is evidenced in the setting up of more referral hospitals, regional hospitals, district hospitals, dispensaries, health centres and clinics, which have gone hand in hand with an increase in the number of medical practitioners, health experts and nurses.

The government also collaborates with the private sector in the provision of health services. Improvement in life expectancy has also boosted Tanzania’s population from 12,313,469 in 1967 to 61,741,120 persons in 2022. The population is projected to reach 151.3 million persons in 2050 [Population and Housing Census (PHC, 2022)].  

Studies show that active physical activity (a healthy lifestyle) removes between six and 10 per cent of the major non-communicable diseases (NCDs) of coronary heart diseases, type 2 diabetes, breast and colon cancer, and increases life expectancy, according to Mainland Tanzania Food-Based Dietary Guidelines (FBDGs, 2023). 

World Health Organisation (WHO) shows a global share of deaths from NCDs rose to 73.9 per cent by 2019, while a share of communicable diseases dropped to 18.2 per cent.

Thus, according to the authors, NCDs account for 41 million (74 per cent) of global annual deaths, with the vast majority of these deaths (77 per cent) occurring in low-and middle-income countries (LMICs).

 “The global demographic and epidemiological transition, with trends such as population aging, increased life expectancy and changes in lifestyle, have led to shifts in the global burden of disease, including increased prevalence of NCDs.” 

Diabetes in particular is one of the top 10 leading causes of death. It is also a major cause of blindness, kidney failure, heart attacks, stroke and lower-extremity amputation, leading to debilitating complications.

“Much of the burden caused by diabetes can be prevented with evidence-based, individual-level and population-level interventions,” says Dr Jerôme Salomon, Assistant Director-General, Universal Health Coverage/Communicable and Non-communicable Disease in a WHO report 2024 titled “Guidance on global monitoring for diabetes prevention and control: Framework, indicators and application.”

The report suggests that the risk of dying from any one of the four main NCDs (cardiovascular diseases, cancer, chronic respiratory diseases or diabetes) between the ages of 30 and 70 decreased by 20 per cent globally between 2000 and 2019. 

However, in lower middle-income countries, the mortality rate of the patients suffering from diabetes, increased by 33 per cent. Countries which have reduced the impact of NCDs have also raised their life expectancy.