Why does the body release CO₂?

A new study had found that the amount of carbon dioxide released by the human body through metabolism has increased significantly over the past three decades.

According to research led by the University of Bath, carbon dioxide emissions from the human body’s natural process of turning food into energy have increased by 74% over the past 30 years.

The study estimates that by 2015, humans worldwide were releasing around 2.05 billion metric tonnes of carbon dioxide every year through breathing and metabolism.

These findings highlight an important part of the Earth’s carbon cycle that had not previously been measured on such a large scale.

How does the human body release carbon dioxide?

The human body produces carbon dioxide as it breaks down food to generate energy.  This gas is then released into the air when people breathe out.

Unlike emissions from burning fossil fuels, such as coal, oil and natural gas the carbon dioxide released by the human body mainly comes from food.

Plants absorb carbon dioxide from the atmosphere during their growth. This carbon then enters the food chain when humans eat plants or animals that feed on plants.

In contrast burning fossil fuels releases carbon that has been stored underground for millions of years. This adds extra carbon dioxide to the atmosphere and affects the natural carbon cycle.

Human carbon dioxide emissions increased by 74%

According to the study published in The Lancet Planetary Health carbon dioxide released through human metabolism increased from 1.18 billion metric tonnes in 1985 to 2.05 billion metric tonnes in 2015.

Researchers also found that more than 60% of this increase was linked to global population growth. The findings help scientists better understand how human activity and population changes influence the Earth’s natural carbon cycle.