People who eat the most red meat and processed meat have higher risks of death from all causes, including heart disease and cancer, says a huge new study in the United States.

The National Cancer Institute study is the largest to look at the highly controversial and emotive issue of whether eating red meat is indeed bad for your health.

Researchers looked at the records of more than 500,000 people aged 50 to 71 who filled out questionnaires on their diet and other health habits.