Does cheese really give you nightmares?

A gouda night’s sleep

Cheese is a staple in the UK, with a market value of £4.84 billion. In fact, data suggests that cheese purchases are rising annually, with the average Brit purchasing 127 grams of cheese weekly. But beyond its popularity, cheese contains casomorphins: compounds derived from milk proteins that can activate the brain’s opioid receptors, affecting mood, reward, and sleep.

With so many people regularly consuming cheese, we wanted to understand its real impact on sleep, especially as questions around cheese-induced dreams continue to surface. In April 2025 alone, over 22,000 people worldwide searched for answers about cheese and dreaming, with queries like “does Stilton cheese make you hallucinate?” gaining traction.

Motivated by this public curiosity and our commitment to helping people sleep better, we decided to put cheese to the test.

The experiment

Over the course of four nights, our experiment saw thirty participants eat a different cheese before bed to assess whether cheese impacts sleep and, if so, which variety is the worst culprit.

On the menu was: 

• Brie: a soft cows-milk cheese
• Mature Blue Stilton: a semi-soft cowsmilk cheese, veined with blue mould
• Mozzarella: our token fresh, non-aged contender
• Cheddar: the nation’s undisputed favourite and a staple hard cheese

What do the experts say?

To understand all things science when it comes to cheese dreams, we spoke with expert Amie Alexander, a Registered Dietitian at Nutri Peak, who told us: 

“The route possibly linking cheese to dreams is its tryptophan composition, an amino acid employed in the synthesis of serotonin and melatonin — neurotransmitters responsible for mood, sleep, and internal body clock regulation. High levels of serotonin may influence REM (rapid eye movement) sleep, during which the most vivid dreaming occurs.

“Cheese contains tyramine, particularly in aged cheeses like Parmesan, Gouda, and Roquefort. Tyramine is said to induce the release of norepinephrine, a stimulant that can increase activity in the heart and brain. This could lead to more intense dreams or more awakenings during REM stages in sensitive people, with the possible subsequent remembering of unpleasant or vivid dreams.”

According to the Mayo Clinic, artisan, handmade, or aged cheeses tend to be high in tyramine. Cheddar and Stilton contain particularly high levels due to their aging processes, while Brie also ranks relatively high in tyramine content. Mozzarella, on the other hand, is a fresh, non-aged cheese typically made from pasteurised milk, meaning it contains significantly lower levels of tyramine.

This might help explain why mozzarella ranks lowest for nightmares; maybe its tyramine levels are slightly more brain-friendly. 

Conclusion 

The moral of the story? You might want to think twice before reaching for a big chunk of cheese before bed, unless you’re happy to trade a peaceful night’s sleep for a whirlwind of strange dreams and middle of the night wake-ups. We’ll definitely be planning our cheese plates firmly pre-7pm. 

Methodology 

To investigate the effects of cheese on sleep and dreaming, we conducted a controlled sleep experiment involving 30 participants over four nights. Participants consumed a different type of cheese each night, with the four selected to represent a broad range of styles and maturities:

• Brie – a soft cow’s milk cheese
• Mature Blue Stilton – a semi-soft cow’s milk cheese veined with blue mould
• Mozzarella – a fresh, non-aged cheese
• Cheddar – a hard cheese and the UK’s most popular variety

To reduce interference, participants were asked to avoid substances known to affect sleep, including alcohol, nicotine, and caffeine.

Each participant provided information about their typical sleep patterns, including:

• Average hours of sleep per night
• Usual sleep quality (rated out of 10)
• Usual wake count per night
• Typical frequency of dreams and nightmares

This data was used as a baseline to measure changes against cheese-related sleep. Participants were asked to conduct the experiment on a night where the sleep conditions were most controlled, such as on a week night, in their own home.  

Data collection & analysis

• Hours of Sleep: The average number of hours slept per cheese night was recorded. This was compared to each participant’s reported baseline to calculate the mean difference in sleep duration.
• Sleep Quality: Participants rated their sleep quality each night on a scale of 1–10 (with 10 being the best possible sleep). The mean sleep quality score for cheese nights was compared to their usual rating, and the percentage change was calculated.
• Wake Count: The number of times participants woke up during the night was recorded and compared against their normal sleep pattern. The mean increase or decrease in wake-ups was calculated across cheeses.
• Dream and Nightmare Frequency:
  • Participants reported whether or not they had any dreams and any nightmares each night (binary yes/no).
  • Baseline dream frequency (e.g., 2 nights out of 5) was compared with dream occurrence during each cheese night.
  • Changes were analysed as a percentage difference from the norm.
  • The same approach was used to measure changes in nightmare frequency.

All reported figures represent mean averages across participants. The experiment took place in May 2025.  Search analysis conducted in May 2025 from Glimpse.