Naomi Elster writes: “There isn’t currently any strong evidence that eating too much red meat causes cancer”, before noting that Cancer Research UK is a “reliable source … for advice and support” (The truth about cancer diets, G2, 16 January). However, responding to the WHO’s October 2015 International Agency for Research on Cancer report which classified red meat as “probably carcinogenic to humans”, Professor Tim Key, Cancer Research UK’s epidemiologist at the University of Oxford, said: “Cancer Research UK supports IARC’s decision that there’s strong enough evidence to classify … red meat as a probable cause of cancer.”

Ian Sinclair

London

• The letter headed “Standing in solidarity with Brazil’s Lula” (14 January) shows a remarkably one-sided view and a lack of concern for the facts. An example: “Investigating Lula, prosecutors have been unable to find any illegal activity committed.” This is nonsense. Lula has been charged on various counts including money laundering, being a member of a criminal organisation, influence peddling and misconduct. More than 50 Brazilian politicians, past and present and from various parties, have been charged with illegal activities and Lula is one of them.

John Fenn

London

• As was said of Wall Street corporations when the US supreme court granted them “personhood”, I’ll believe robots are people when the state of Texas executes one (Letters, 17 January).

John Smith

Sheffield

• I don’t know about corned beef as I don’t buy it, but Spam has replaced the old key opening with a ring pull, presumably to reduce hand injuries (Letters, 17 January).

Michael Cunningham

Wolverhampton

• I have crunchy peanut butter on Weetabix (Letters, 17 January). My family think I’m weird, though they appreciate my lack of conversation over breakfast.

Lynn Alexander

Barton le Clay, Bedfordshire

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