From Mark Inwood, Reigate, Surrey, UK
You report that irritable bowel syndrome (IBS) could be a nocebo effect for some people. I have for several decades relied on the opposite effect from what I call my “placebo tablets”. They keep me IBS symptom-free despite having only a few Lactobacilli and Bifidobacteria, along with minerals and vitamins(2 August, p 17).
