Can Cheese Really Cause Nightmares? New Study Explores Dairy-Dream Link

Picture this: a late-night snack of creamy brie or sharp cheddar, followed by a restless night filled with vivid, unsettling dreams. For years, folklore has whispered that cheese before bed invites nightmares. A 2025 study published in Frontiers in Psychology lends credence to this age-old belief, revealing a surprising link between dairy consumption, particularly in lactose-intolerant individuals, and disturbing dreams. This research not only validates cultural anecdotes but also shines a light on how diet influences sleep quality and dream content.

The study, conducted by researchers at MacEwan University in Canada, surveyed over 1,000 students to explore how food choices, sensitivities, and eating habits affect sleep and dreams. The findings point to a strong connection between lactose intolerance, gastrointestinal discomfort, and nightmares. This revelation challenges the notion that nightmares are solely tied to stress or mental health, suggesting that what lands on the dinner plate could play a significant role in nighttime terrors.

As sleep disorders affect millions—approximately 56% of Americans and 31% of Western Europeans, according to estimates—these findings offer a fresh perspective on improving sleep through dietary adjustments.

The Dairy-Nightmare Connection

Key Study Findings

The Frontiers in Psychology study, published on June 30, 2025, surveyed 1,082 college-aged students about their sleep quality, dream experiences, and dietary habits. The results revealed intriguing patterns:

• Dairy and Nightmares: About 22% of participants who reported food-related dream disturbances blamed dairy products, such as cheese, milk, and yogurt, for vivid or unsettling dreams. Desserts and sweets topped the list at 31%.
• Lactose Intolerance Link: Participants with lactose intolerance reported more frequent and intense nightmares, especially when experiencing gastrointestinal symptoms like bloating, cramping, or gas.
• Sleep Quality Impact: Those with food sensitivities, particularly lactose intolerance, experienced poorer sleep quality, often due to micro-arousals—brief awakenings that disrupt sleep and enhance dream recall.
• Other Foods Implicated: Spicy foods, meats, and cereals were also linked to disturbed sleep, though dairy and sweets were the primary culprits.
• Healthy Diets, Better Dreams: Diets rich in fruits, vegetables, and herbal teas correlated with improved sleep quality and fewer nightmares.

Why Dairy Disrupts Dreams

The study suggests that gastrointestinal discomfort is the primary mechanism linking dairy to nightmares. For lactose-intolerant individuals, consuming dairy can trigger bloating, cramping, or gas, which may disrupt sleep. These disturbances, often subtle, can lead to micro-arousals during REM (rapid eye movement) sleep, the stage where most vivid dreams occur. As a result, dreams may feel more intense, bizarre, or disturbing.

Dr. Tore Nielsen, lead author and professor at the Université de Montréal, explains, “Nightmare severity is robustly associated with lactose intolerance and other food allergies. These findings imply that changing eating habits for people with some food sensitivities could alleviate nightmares.” The gut-brain axis, a complex communication network between the digestive system and the brain, likely plays a role. Physical discomfort from dairy can heighten psychological stress, which manifests in dream content.

Cultural Roots of the Cheese Myth

The idea that cheese causes nightmares isn’t new. In Charles Dickens’ A Christmas Carol, Ebenezer Scrooge dismisses his ghostly visions as the result of “a crumb of cheese.” Similarly, the early 20th-century comic strip Dreams of the Rarebit Fiend by Winsor McCay depicted bizarre dreams blamed on eating Welsh rarebit, a cheesy dish. These cultural references highlight a long-standing suspicion that dairy disrupts sleep, now backed by scientific evidence.

Broader Dietary Impacts on Sleep

Foods That Harm Sleep

The study identified several food groups linked to poor sleep and nightmares, with dairy being a significant but not solitary contributor. Key findings include:

• Desserts and Sweets (31%): Sugary foods were the most frequently cited culprits for disturbing dreams, possibly due to blood sugar spikes that disrupt sleep.
• Spicy Foods (13%): These can cause indigestion or acid reflux, leading to discomfort that infiltrates dreams.
• Late Hannah Foods: Meats and cereals also appeared on the list, though their impact was less pronounced than dairy or sweets.

Foods That Help Sleep

On the flip side, certain foods were associated with better sleep quality and fewer nightmares:

• Fruits (18%): Regular fruit consumption correlated with improved sleep, likely due to their nutrient density and lack of digestive irritants.
• Vegetables (12%): High in fiber and vitamins, vegetables support overall health and digestion, reducing sleep disruptions.
• Herbal Teas (13%): Caffeine-free options like chamomile or lavender promote relaxation and better sleep.

Timing Matters

Eating habits, particularly the timing of meals, also influence sleep. The study found that late-night eating or snacking when not hungry was linked to poorer sleep quality and more disturbing dreams. Eating close to bedtime can disrupt the body’s “rest and digest” phase, leading to discomfort that affects sleep architecture.

The Science Behind Food and Dreams

The Gut-Brain Axis

The gut-brain axis is a bidirectional communication system between the digestive tract and the brain. Gastrointestinal distress, such as bloating from lactose intolerance, sends signals to the brain that can increase anxiety or stress, influencing dream content. This connection explains why physical discomfort during sleep may lead to emotionally charged or disturbing dreams.

Micro-Arousals and REM Sleep

Micro-arousals are brief awakenings that occur without fully waking a person. These interruptions, often triggered by digestive discomfort, are more likely during REM sleep, when dreams are vivid. As a result, individuals may recall dreams more clearly, especially if they are unsettling. Dr. Patrick McNamara, a neurology professor at Boston University, notes that these micro-arousals can intensify nightmare experiences.

Psychological Factors

The study also found that anxiety and depression symptoms partially mediate the link between food sensitivities and nightmares. Gastrointestinal discomfort can exacerbate stress, which may carry over into sleep, fueling negative dream content. This interplay between physical and psychological factors underscores the complexity of the food-dream relationship.

Practical Tips for Better Sleep

For those looking to improve sleep quality and reduce nightmares, dietary adjustments can make a difference. Here are actionable tips based on the study’s findings and expert advice:

• Time Meals Wisely:
  • Finish eating 2–3 hours before bedtime to allow proper digestion.
  • Avoid late-night snacking, especially on trigger foods like dairy or sweets.
• Choose Sleep-Friendly Foods:
  • Opt for light, digestible snacks like nut butter with fruit or hummus with vegetables.
  • Incorporate fruits, vegetables, and herbal teas into evening routines.
• Avoid Problematic Foods:
  • Steer clear of dairy if lactose intolerant.
  • Limit spicy foods, heavy meals, or caffeine close to bedtime.
• Keep a Food Journal:
  • Track meals and sleep patterns to identify correlations between specific foods and nightmares.
  • Note any digestive symptoms that may disrupt sleep.
• Stay Hydrated:
  • Drink water or caffeine-free herbal teas to support digestion and relaxation.
• Consult a Professional:
  • Work with a registered dietitian nutritionist to address food intolerances and tailor dietary plans.

Limitations and Future Research

The Frontiers in Psychology study provides compelling insights but has limitations. The participant pool, primarily college-aged students, may not represent the broader population. Additionally, the study relies on self-reported data, which can introduce bias, especially among psychology students familiar with sleep-related concepts. The researchers acknowledge that causation is’t fully established—poor sleep could lead to poor eating habits, or vice versa.

Future research aims to address these gaps. Dr. Nielsen and his team plan to conduct experimental studies, such as comparing the effects of dairy versus control foods on sleep and dreams. Expanding the study to diverse age groups and incorporating wearable sleep technology or biomarker data could further clarify the mechanisms behind food-induced nightmares.

Key Facts and Findings

• Study Scope: Surveyed 1,082 students at MacEwan University, January–April 2023.
• Nightmare Prevalence: About one-third of participants reported frequent nightmares.
• Dairy’s Role: 22% of participants linked dairy to disturbing dreams, second only to sweets (31%).
• Lactose Intolerance Impact: Strong association between lactose intolerance, gastrointestinal symptoms, and nightmare severity.
• Sleep Quality: Poor diets correlated with worse sleep and more nightmares; fruits, vegetables, and herbal teas linked to better sleep.
• Mechanisms: Gastrointestinal distress, micro-arousals, and the gut-brain axis drive the dairy-nightmare link.
• Cultural Context: Historical references, like A Christmas Carol and Dreams of the Rarebit Fiend, align with study findings.

Sweet Dreams Through Smart Eating

The Frontiers in Psychology study marks a significant step in understanding how diet, particularly dairy, influences sleep and dreams. For lactose-intolerant individuals, the connection is clear: gastrointestinal discomfort can disrupt sleep, leading to vivid, unsettling dreams. Yet, the findings extend beyond dairy, highlighting the broader impact of eating habits on sleep quality. By choosing sleep-friendly foods, timing meals appropriately, and tracking dietary patterns, individuals can take control of their nighttime experiences.

These insights resonate with centuries-old wisdom, from Scrooge’s skepticism to comic strip exaggerations, proving that folklore sometimes holds a kernel of truth. As research continues, simple dietary tweaks could offer a low-risk way to improve sleep and reduce nightmares, benefiting the millions grappling with sleep disorders. For now, those prone to nightmares might reconsider that late-night cheese platter, opting instead for a light, digestible snack to pave the way for sweeter dreams.

FAQs

1. Does cheese cause nightmares for everyone?
   No, the study suggests cheese is more likely to cause nightmares in lactose-intolerant individuals due to gastrointestinal discomfort.
2. What foods besides dairy were linked to nightmares?
   Desserts and sweets (31%), spicy foods (13%), meats, and cereals were associated with disturbing dreams.
3. How does lactose intolerance contribute to nightmares?
   Lactose intolerance can cause bloating, cramping, or gas, which disrupts sleep and intensifies dream experiences.
4. What are micro-arousals, and how do they affect dreams?
   Micro-arousals are brief awakenings during sleep, often during REM, that can make dreams feel more vivid or unsettling.
5. Can certain foods improve sleep quality?
   Yes, fruits (18%), vegetables (12%), and herbal teas (13%) were linked to better sleep and fewer nightmares.
6. Why does eating late at night affect sleep?
   Late-night eating can disrupt digestion, leading to discomfort that interferes with sleep and increases nightmare frequency.
7. What is the gut-brain axis, and how does it relate to dreams?
   The gut-brain axis connects the digestive system and brain, allowing physical discomfort to influence dream content.
8. How reliable is the study’s data?
   The study relied on self-reported data from college students, which may introduce bias and limit generalizability.
9. What future research is planned?
   Researchers plan experimental studies comparing dairy and control foods and studies with diverse populations.
10. How can someone reduce food-related nightmares?
    Avoid trigger foods, eat 2–3 hours before bed, choose light snacks, and track dietary patterns to identify sensitivities.