Study shows replacing common food in your diet could increase life expectancy

The University of Sydney in Australia has found that residents of countries who eat more plant-based proteins were more likely to have longer adult life expectancies than those who eat more animal-based proteins. 

The research, published in the journal Nature in 2025, analyzed public data on the food supply of 101 countries from 1961 to 2018. 

It factored in the amount of food produced by every nation, as well as the calories, proteins, and fats available for each one to consume. 

The sample included nations that consumed more animal protein, such as Australia, the U.S., Sweden, and Argentina, and those where plant protein was more prevalent, such as Pakistan and Indonesia. 

After correcting the data to account for differences in population size and wealth across all countries, the researchers found that infant mortality rates were lower in nations with food systems that prioritized animal-based proteins, such as meat, eggs, and dairy products. 

However, longer adult life expectancy was associated with countries that consumed more plant-based proteins, such as legumes, nuts, and whole grains.

The university noted that diets heavy in animal-based protein are connected to chronic health issues, such as cardiovascular disease, type 2 diabetes, and some types of cancer. 

Meanwhile, diets in which plant-based proteins take precedence are linked to a lower risk of chronic diseases and mortality. 

Their benefits also extend to the planet. Whereas beef production has generated 20,000 megatons of carbon dioxide over the last 20 years and has contributed to deforestation, transitioning to a plant-based diet can help slash the amount of planet-warming gases entering the atmosphere.

"Protein is a crucial part of the human diet, but as eating habits change and developed countries look to decarbonize, where we get our protein from has come under greater scrutiny," lead investigator Dr. Alistair Senior said.

"The knowledge that plant-based protein is associated with a longer life is really important as we consider not only how our diets impact our own longevity, but the health of the planet."

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