One of the most concerning findings was published in the journal Cell Metabolism.
The study found that people who eat a high-protein diet during middle age are more likely to die of cancer than those who eat less protein.
“We studied simple organisms, mice, and humans and provide convincing evidence that a high protein diet – particularly if the proteins are derived from animals – is nearly as bad as smoking for your health,” said study researcher Valter Longo, professor of biology at the University of Southern California (USC) and director of the USC Longevity Institute.
However, for people older than 65, a moderate protein intake may actually be beneficial, and protect against frailty, the researchers noted.
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