If you often drink a glass of warm milk before bed to relax, you may want to reconsider. A recent study found a surprising link between consuming dairy products in the evening and strange dreams, even nightmares.
Milk, sweets and scary dreams
The study, authored by Dr. Tore Andre Nielsen, Professor of Psychology at the University of Montreal ( Canada), is presented in an article published on verywell Health in 2025, written by Stephanie Brown and clinically certified by Jennifer Klump, RDN. This study was conducted on more than 1,000 participants, aiming to understand how foods affect sleep and sleep. The results showed that dishes such as milk, cheese, yogurt and sweet desserts were the foods most closely associated with nightmares.
According to Dr. Tore Andre Nielsen, people with lactose intolerance often have severe digestive symptoms at night such as bloating, cramps and they also experience more severe nightmares. A feeling of discomfort at night, such as stomach pressure or abdominal pain, can creep into dreams and turn them into negative experiences, explains Nielsen.
Why can eating late affect sleep?
Not only milk, eating too close to bedtime, especially when the body is full can also negatively affect sleep. People with digestive problems such as reflux, stomach ulcers or irritable bowel syndrome (IBS) are also noted for having poor sleep quality and being more prone to nightmares.
If a food is digestive disorder and disrupts sleep, you tend to remember more dreams, especially negative dreams, says Dr. Jennifer L. Martin, a sleep expert at the University of California, Los Angeles (UCLA).
Another hypothesis given by Dr. Thomas Kilkenny, Director of the Institute of Sleep Medicine at the University of Staten Island Hospital (USA), is that the discomfort of intolerance to milk causes stress on the body, thereby leading to bad dreams. Although it is not possible to confirm that milk is the cause of nightmares, there is clearly a connection, he said.
Should you stop drinking milk before bed?
Research cannot conclude that dairy products directly cause nightmares. However, for people who are sensitive to lactose, limiting the consumption of milk, cheese, ice cream or sweets in the evening is a useful advice.
According to Dr. Martin, the worst snack before bed is ice cream, which is both rich in fat and easily causes indigestion.
In addition, keeping a log of your sleep and diet can help you track the link between food and sleep quality. Kilkenny suggests: If you often have nightmares after eating dairy products, try to stay away from them for a while and monitor the changes. You can also try supplementing with lactase if you are lactose intolerant.
How to sleep better?
In addition to paying attention to your diet, experts recommend:
Avoid alcohol and caffeine in the evening
Don't eat dinner too late or too full
Maintain regular sleep and wake times
Avoid using phones and computers close to bedtime
We often focus on improving the sleep habits of nightmares, not simply eliminating a certain food, says Dr. Martin.
If you often have uncomfortable dreams and have the habit of eating sweets or drinking milk before bed, try changing them. Improving your evening routine can help you have a gentle sleep and better dreams.
