Scientists in the USA say that eating five mushrooms a day could ward off heart disease, cancer and dementia. The fungi are also rich in two key antioxidants that combat ageing and boost the brain, scientists in the United States say. Their research, published in the journal Food Chemistry, found that countries in which consumption was high, such as France and Italy, had fewer cases of Alzheimer’s disease than those that ate less, such as the US. The average difference in intake is only 3 milligrams a day, equivalent to five button mushrooms. The fungi contain the antioxidants ergothioneine and glutathione, which destroy harmful chemicals released by the body.

Robert Beelman, of Pennsylvania State University, said that porcini mushrooms were the most beneficial.