Late-night dairy snacks might be doing more than weighing on your stomach — they could be haunting your dreams, too.
According to the New York Post, A new psychological study has found a notable link between nightmares and lactose intolerance, with cheese and other dairy products emerging as common triggers for disturbing dreams among university students in Canada.
The research, published in the scientific journal Frontiers in Psychology, surveyed 1,000 students at MacEwan University in Alberta to analyze connections between dietary habits and sleep disturbances. Participants were asked to reflect on the foods they typically consume late at night and any related sleep issues.
Roughly one-third of those surveyed reported experiencing nightmares regularly. Common culprits among food items were sweets, spicy meals and, most frequently mentioned, dairy products — particularly cheese.
Tore Nielsen, the study’s lead author from Université de Montréal, said the data points to a relationship between nightmare frequency and food sensitivity, particularly for those with lactose intolerance. “Nightmare severity is robustly associated with lactose intolerance and other food allergies,” Nielsen said.
The research suggests these intense dreams may be triggered or worsened by physical discomfort that disrupts a person’s rest. “Nightmares are worse for lactose-intolerant people who suffer severe gastrointestinal symptoms and whose sleep is disrupted,” Nielsen explained.
He noted that this disruption could help explain why those with food sensitivities frequently report creepy or vivid dreams. “This makes sense, because we know that other bodily sensations can affect dreaming,” he added.
Although 40% of participants believed certain foods negatively impacted their sleep, only a small percentage — just 5.5% — believed their nighttime snacks affected their dreams directly. Nonetheless, among those who did, dairy emerged as the primary suspect.
The association between dairy and unpleasant dreams isn’t new. Folklore and pop culture references have long tied rich nighttime snacks to unsettling visions. In Charles Dickens’ “A Christmas Carol,” the character Ebenezer Scrooge famously attributes his ghostly visitation to a “blot of mustard” or “undigested bit of beef, a crumb of cheese.”
Yet scientific consensus has historically been mixed. A 2005 study by the British Cheese Board tracked 200 participants and found no evidence linking cheese to nightmares — in fact, it claimed cheddar could promote more pleasant dreaming experiences.
Despite past skepticism, the new findings reignite the conversation around how digestion and diet impact mental activity while sleeping. Nielsen and his team say that these modern insights may back up what past generations have suspected for centuries.
The recent findings have produced a call for more extensive, diverse follow-up studies. Nielsen emphasized that the surveyed group consisted mainly of students from the same university, lacking variability in age, background and diet.
“We need to study more people of different ages, from different walks of life, and with different dietary habits to determine if our results are truly generalizable to the larger population,” he said. The current study focused on self-reporting by a relatively homogenous sample, which may not reflect wider societal patterns.
Nielsen also proposed future experimental studies as the next logical step for exploring this phenomenon. “We would like to run a study in which we ask people to ingest cheese products versus some control food before sleep to see if this alters their sleep or dreams,” he said.
While researchers have not established causation, they have observed strong correlations in this study that could eventually lead to practical applications. Nielsen noted that altering late-night eating habits might help mitigate nightmare frequency in those with food sensitivities.
“These new findings imply that changing eating habits for people with some food sensitivities could alleviate nightmares. They could also explain why people so often blame dairy for bad dreams,” he suggested.
The data also found that women were more likely than men to recall their dreams and to report having food allergies, hinting at possible gender-related differences in both nutritional response and dream recollection.
All said, the study’s authors urge moderation and awareness — not panic — when it comes to bedtime snacking. Especially for those who regularly experience nightmares, avoiding certain foods in the evening may be a simple and helpful adjustment.
