New research suggests that cheese could give people nightmares. A study in a journal found that people with a severe lactose intolerance were more likely to have bad dreams and insomnia. The director of the Dream and Nightmare Lab in Canada analyzed the diet, health and sleep patterns of 1,000 people. She wanted to investigate how food affected dreams. The director based her research on a 2015 study that looked into "food-dependent dreaming". Participants in that study blamed cheese and other dairy products for disrupting their sleep.

The director found that people with stomach problems and lactose intolerance had scarier and more frequent nightmares. She said: "Gastrointestinal issues…could account for a lot of what's happening in terms of sleep disturbances [and] different dreams." Her colleague said: "Sleep disturbances affect a huge proportion of the general population." Around 35 per cent of people could have a clinically significant sleep disorder. Research suggests that about 85 per cent of adults have a nightmare at least once a year. About 5 per cent of people have one frequently.