A study by The Lancet, a peer-reviewed medical journal, has shown tobacco, unhealthy diet, and high blood sugar to be the leading causes of cancer deaths globally. The Lancet released the report on Wednesday.

Breast cancer was the prevalent cancer that affected both genders in 2023, experts said. Men who drink alcohol and smoke tobacco are susceptible to cancer, while women who are obese and practise unsafe sex run a higher risk of having cancer.

Of the 18.5 million new cancer cases discovered as of 2023, 42 per cent of 10.4 million cancer deaths were preventable if patients had steered clear of tobacco and unhealthy meals, the study showed.

“A greater proportion of global cancer deaths in men (46%) in 2023 were linked to potentially modifiable risk factors (mostly tobacco, unhealthy diet, high alcohol use, occupational risks, and air pollution) than in women (36%), for whom the leading risk factors were tobacco, unsafe sex, unhealthy diet, obesity, and high blood sugar,” it stated.

While cancer deaths have been projected to reduce in developed nations, researchers said low and middle-income countries should prepare for the worst if new health policies are not urgently formed and implemented.

“Although global rates for cancer deaths (when adjusted for age) have decreased, this is not the case for some low- and middle-income countries where rates, as well as numbers, are on the rise,” the report stated.

New cancer cases are forecasted to rise by 30.5 million in 2050, with a death toll of 18.6 million. At least half of these figures are expected to be recorded in low and middle-income countries, which is far from the UN Sustainable Development Goals to reduce premature deaths caused by non-communicable diseases, including cancer.

“Cancer remains an important contributor to disease burden globally, and our study highlights how it is anticipated to grow substantially over the coming decades, with disproportionate growth in countries with limited resources,” said lead author Lisa Force from the Institute for Health Metrics and Evaluation, University of Washington.

Between 1990 and 2023, Lebanon had the highest cancer cases in age-standardised incidence and mortality rates for both genders. The UAE recorded the highest decline in age-standardised incidence, while Kazakhstan recorded the largest reduction in age-standardised death rates.

Ms Force said the government should use their predictions to develop data-informed policies and actions to improve cancer control and outcomes around the world.

She added, “They can also support tracking of progress towards global and regional cancer targets.”