Nighttime Dairy: An Invitation To Disturbing Dreams

Research shows that what we eat can influence our dreams and the quality of our sleep. Foods such as sweets and dairy products are linked to more nightmares, especially in people with intolerances such as lactose. On the other hand, a healthy diet and avoiding eating at night can improve sleep and make dreams more pleasant.

For centuries, many people have believed that certain foods, especially heavy or spicy ones, can cause strange dreams or even nightmares. Who has never heard that “eating cheese before bed gives you nightmares”?

This idea is not new: in the early 20th century, cartoonist Winsor McCay already depicted characters having bizarre dreams after eating cheese dishes, such as the famous Welsh rarebit (toast with melted cheese and pepper).

Although these beliefs are common in the popular imagination, until recently there was little scientific research to support them. Today, however, science is beginning to investigate this connection more systematically and with modern tools.

Preliminary studies have found that what we eat may indeed be related to the type and frequency of our dreams. For example, people who eat more fruit report more lucid dreams (dreams in which we know we are dreaming), while eating sweets is associated with more frequent nightmares.

However, these studies still face limitations, as factors such as age, personality and lifestyle also influence dreams, and when these factors are taken into account, some of these associations disappear. In other words, it is not yet possible to draw definitive conclusions.

A more recent line of research has sought to understand not only whether food influences dreams, but how this might happen. A study of almost 400 university students showed that almost 18% of them believed that their dreams were influenced by what they ate, and dairy products were the most cited food.

These same students also reported having more disturbing dreams and less confidence in their own hunger and fullness cues, as well as a greater tendency to eat for emotional reasons.

Based on these findings, scientists have proposed several possible explanations for the link between food and dreams. One hypothesis is that certain foods do in fact directly affect the brain and dreams (e.g., stimulants or foods high in sugar). Another possibility is that food causes physical discomfort, such as gastrointestinal symptoms caused by food intolerances, which in turn affect the content of dreams.

There is also the idea that some people simply attribute what they ate to things that actually have other causes (such as stress). And finally, there is the hypothesis that food affects the quality of sleep, which indirectly influences dreams; this last hypothesis has been increasingly supported by studies.

Larger and more recent studies confirm that the relationship between food and sleep is real. A study with more than a thousand participants investigated whether certain foods alter sleep and dreams.

About 40% of people said food affects their sleep (either making it better or worse), and 5.5% reported that it specifically affects their dreams. Sweets and dairy products were again the top foods cited as causing bad dreams.

In addition, people with food allergies, lactose intolerance or gluten intolerance also reported more nightmares. Lactose intolerance, for example, appears to cause gastrointestinal symptoms that disrupt sleep, and this in turn increases the chance of having nightmares.

On the other hand, healthier eating habits, such as avoiding eating at night or maintaining a balanced diet, were associated with better dream recall and fewer negative experiences during sleep. Irregular eating, especially at night, was associated with more disturbing dreams and more negative content.

In short, although much remains to be studied, current evidence suggests that yes, food can influence both sleep quality and dream content. This can happen through direct effects on the brain, physical discomfort, or changes in sleep patterns.

The good news is that these discoveries may pave the way for new ways to improve sleep and even prevent nightmares, simply by adjusting our diet. An area of ​​science that, until recently, was considered folklore, is now beginning to be taken seriously by neuroscience.

READ MORE:

More dreams of the rarebit fiend: food sensitivity and dietary correlates of sleep and dreaming

Tore Nielsen, Jade Radke, Claudia Picard-Deland, and Russell Arnold Powell 

Front. Psychol., 01 July 2025. Volume 16 - 2025 

https://doi.org/10.3389/fpsyg.2025.1544475

Abstract: 

Background: Despite centuries-old beliefs and anecdotal evidence that food can influence one's sleep and dreams—an example being the classic Dream of the Rarebit Fiend cartoon series—the topic has only rarely been researched.

Methods: We asked 1,082 participants to complete an online survey to test specific hypotheses on why people perceive that food affects their dreams, including whether specific foods influence dreams directly (food-specific effects), through physiological symptoms (food distress), or via altered sleep quality (sleep effects). Survey measures included standard demographic variables, targeted probes about self-perceived effects of specific foods on dreams, questions about diet, food intolerances and allergies, personality questionnaires, measures of sleep quality (Pittsburgh Sleep Quality Index) and the Nightmare Disorder Index.

Results: A total of 40.2% of participants reported that certain foods either worsened (24.7%) or improved (20.1%) their sleep, while 5.5% of participants reported that food affected their dreams. The perceived effect of food on dreams was associated with higher nightmare recall and Nightmare Disorder Index scores, with changes being blamed primarily on desserts/sweets (31%) and dairy (22%). The effect was also associated with food allergies and Gluten Intolerance, while worse sleep perceptions were tied to Lactose Intolerance. Nightmare Disorder Index scores were strongly associated with Food Allergy and Lactose Intolerance, the latter being mediated by the severity of gastrointestinal symptoms. Healthy eating, such as less evening eating, predicted higher dream recall, while unhealthy eating—including gastric symptoms, lower reliance on hunger and satiety cues, and evening eating—predicted nightmares and dream negativity.

Conclusions: These results support the food-specific effects, food distress, and sleep effects hypotheses to varying degrees. They replicate associations between diet and dream features, highlighting food sensitivities, particularly Lactose Intolerance, as contributors to nightmare prevalence. Findings open new avenues of research on food-dependent dreaming by suggesting dairy-induced gastrointestinal symptoms as one plausible basis for bizarre or disturbing dreams. They have clear implications for understanding how dietary factors may influence sleep quality and the occurrence of nightmares and could inform non-pharmacological interventions for sleep disturbances.