A massive study showed that every three per cent increase in calories from plant protein reduced the risk of death by a massive 10 per cent.
The study claims this drop is a percentage of all causes of death and that replacing meat proteins with plant was also associated with a 12 per cent lower risk of death from heart disease.
In contrast, raising the animal protein share of calories by 10 per cent led to a two per cent higher risk of all-cause death and an eight per cent greater chance of dying from a heart problem.
Animal protein foods include all types of meat, fish, eggs and dairy products such as milk and cheese. Plant sources of protein include cereals, beans, nuts, legumes, soya and bread.
Among the healthiest participants, the association disappeared – possibly because health-conscious people tended to eat more fish and poultry rather than red and processed meat, said the researchers.
Replacing processed red meat with plant protein was linked to a 34 per cent lower risk of death from all causes for every three per cent of calorie intake.
Substituting plant protein for eggs led to a 19 per cent reduction in death risk.
Lead scientist Dr Mingyang Song, from Massachusetts General Hospital, US, said: “Overall, our findings support the importance of the sources of dietary protein for long-term health outcomes.
“While previous studies have primarily focused on the overall amount of protein intake – which is important – from a broad dietary perspective, the particular foods that people consume to get protein are equally important.