Around 2.7 billion people worldwide are exposed to secondhand smoke

Around 2.7 billion people were exposed to secondhand smoke worldwide in 2023, and the resulting health burden remains largely unchanged despite lower exposure rates since 1990, according to a new Global Burden of Disease study.

Researchers assessed exposure and health effects across 204 countries and territories from 1990 through 2023. Secondhand smoke contributed to the loss of 44.8 million disability-adjusted life years, keeping it a major factor in disability and premature death.

Women and children were among those most affected. In 2023, about 1.4 billion women were exposed to secondhand smoke, and prevalence in some countries was nearly 1.8 times higher among women than men. Children accounted for more than 12% of the health burden, with lung infections the main source of harm.

Ischemic heart disease caused 12 million disability-adjusted life years linked to secondhand smoke, making it the leading cause of related health loss that year. Exposure nearly doubled in sub-Saharan Africa from 1990 and rose 72.1% in North Africa and the Middle East.

Global exposure prevalence stood at 33.9% in 2023, reaching 48.4% in Southeast Asia, East Asia and Oceania. China, India and Indonesia together accounted for nearly half of the exposed population, with 664 million, 444 million and 142 million people affected, respectively. The study’s authors called for broader, sustained tobacco-control measures and voluntary restrictions on smoking in homes and private vehicles.