The surprising foods fueling your insomnia and strange dreams — Published: 14:16 BST, 6 September 2026 | Updated: 14:22 BST, 6 September 2026
Drinking a warm glass of milk to help wind down before bedtime may actually be keeping you awake, according to experts.
Scientists have discovered a surprising link between poor sleep and eating late-night snacks, particularly dairy products and desserts. 
In a recent study, researchers surveyed participants about their sleep quality, eating habits, and any perceived link between the two. 
Participants completed questionnaires, including the Pittsburgh Sleep Quality Index and Nightmare Disorder Index, to assess their sleep and dream experiences.
Results showed that healthier evening eating habits led to better sleep and dream recall, while dairy, desserts, spicy foods, and meat consumed before bed were linked to nightmares and insomnia.
The study also found a strong link between lactose intolerance and nightmares, with scientists suggesting that gastrointestinal issues or stomach pain at night may impact sleep quality.
Ultimately, experts say it is unclear how the exact relationship between sleep and diet works, but found a strong link between lactose intolerance and poor sleep in particular.
There is previous evidence that gastrointestinal distress and nighttime GI symptoms can disrupt sleep – a 2019 study published in PubMed studied 2,752 participants and found sleep disturbance was associated with GI conditions, including gastroesophageal reflux disease (GERD) and irritable bowel syndrome (IBS).
More broadly, research on nighttime reflux shows that when you're asleep, the mechanisms that normally clear acid from the esophagus work less effectively and therefore nighttime reflux can cause sleep disruption.
Healthier evening habits lead to better sleep and recall of dreams, while the consumption of dairy, desserts, spicy foods, and meat products, have been linked to nightmares and insomnia
In the recent study, published in Frontiers in Psychology, researchers asked 1,082 students – with an average age of 20 – to complete the Pittsburgh Sleep Quality Index, a 19-item self-report questionnaire that measures sleep quality and disturbances over a one-month period, as well as the Nightmare Disorder Index, a brief five-item questionnaire designed to screen for nightmare disorders. 
Participants were also asked about their diet, food intolerances, allergies, and the self-perceived effects of specific foods on their dreams. 
More than 40 percent of participants said eating a late-night snack or specific food affected their sleep, for better or worse.
Twenty percent of participants said their sleep was improved by certain foods, such as fruit, herbal tea, and vegetables, compared to 24.7 percent who said certain snacks such as desserts, dairy, and spicy foods, worsened it.