Factory farming is decreasing the lifespan of human beings globally due to risk of diseases attached to the method, according to new research published by charity organisation, World Animal Protection (WAP).

In the December 2, 2025, report titled ‘The Factory Farming Index,’ the animal advocacy group said the study was the first-of-its-kind one to document the effects of human exposure to animals reared in factories on a large scale around the world.

According to the report, the production of factory-farmed animals surpassed 76 billion globally in 2020, with the United States, China, Indonesia and Brazil, accounting for 46 per cent of pigs and cows produced.

Israel, Panama, Belarus, and Qatar are countries with the highest per capita when it comes to consumption of factory-farmed animals, which means one individual in those nations consume an estimated 10 animals per year, the report noted.

Despite factory farming making it easier to access meat products around the world, WAP has found that chickens, pigs, and cows for eggs, meat and dairy from those farms are causing one person, on average, to lose 1.8 years of healthy life globally. 

The research found that this was due to large scale medicine, including antibiotics needed to keep the population of animals in factories healthy, which could then be detrimental to the health of humans.

Consuming factor-famed meat also increases the risk of pulmonary disease in consumers due to the large volume of animal excreta factory farms emit ammonia, nitrous oxide and fine particulate matter, the report showed.

Furthermore, excessive consumption of particularly red meat and processed meat is linked to colorectal cancer, heart disease, type 2 diabetes, stroke, kidney disease, and possibly dementia, contributing to the drop in life expectancy.

The report also concluded that factory farming has contributed to climate changes, including being responsible for 29.7 per cent of total greenhouse gas emissions, 25 per cent of human-caused water pollution, and 14 per cent of freshwater withdrawals. 

“We need to support countries in looking to the future of how they feed their populations without damaging human health, animals, and our planet,” Tricia Croasdell, CEO of World Animal Protection said. “This research is clear: in order to achieve a better quality of life for people, we need a better quality of life for animals.”

She added, “This ultimately means prioritising plant- based diets, ending factory farming, and reducing the environmental impact that we are all facing if we don’t act.”