I have recently discovered an intolerance to food preservatives and MSG which result in bad insomnia. Since I realized what was causing my problem I have mostly had really good nights' sleep but occasionally I get caught out and eat something with preservative or MSG without realising. It was probably easier for me to identify the connection between preservatives and insomnia than for most people as we live on a farm and butcher our own meat, hence sausages and mince with little else added, and additionally my husband has a cholesterol problem so I am very careful with our diet. - Karen O'Connor, Victoria.