Science Fictions: How Fraud, Bias, Negligence, and Hype Undermine the Search for Truth

by Stuart Ritchie

In a now-classic paper entitled ‘Is everything we eat associated with cancer?’, researchers Jonathan Schoenfeld and John Ioannidis randomly selected fifty ingredients from a cookbook, then checked the scientific literature to see whether they had been said to affect the risk of cancer.100 Forty of them had, including bacon, pork, eggs, tomatoes, bread, butter and tea (essentially all the aspects of that Killer Full English). Some foods apparently raised the risk, some reduced it, and some had different effects in different studies. We know that numbers are noisy, so we’d expect the literature to look untidy. We should, however, ask ourselves what’s more likely: that 80 per cent of a sample of commonly consumed foods genuinely have an impact, often a large one, on our risk of cancer; or that the low standards of the field led to the publication of poor-quality, p-hacked studies that capitalised on chance, misleading us into thinking many staple foods are either dangerous or guarantors of a long, healthy life?101