Do Certain Foods Really Cause Bad Dreams?
New research investigates age-old folklore about diet and dreams.
Posted Jan 26, 2015
“It is no humorist’s fancy that the rarebit is a thing of dreams. Clothed in gold and breathing a fragrance that fills the nostrils with a charm more bewitching than woodland odors, it is, to a soul attuned to its beauties, a thing of glorious reverie by day and matchless dreams by night.” —Randolph C. Lewis, “Rarebit Symbolism,” in Winsor McCay, Dreams of the Rarebit Fiend (Frederick A. Stokes Company, 1905)
Drawing inspiration from the early 20th-century comic of the same name, a recent research article entitled “Dreams of the Rarebit Fiend: Food and Diet as Instigators of Bizarre and Disturbing Dreams” investigates the common belief that foods can influence our nightly dreams (Nielsen & Powell, 2015).
The comic was known for its depiction of a particular spicy cheese dish, Welsh rarebit, as the continual culprit to the nocturnal misadventures of its protagonist. This, of course, begs the question: Could cheese really be to blame for disturbing dreams?
Apparently, this belief is so widely held that in 2005, the British Cheese Board conducted one of the only studies to date attempting to empirically assess the effects of food on dreams, in an effort to absolve cheese from its nightmarish image. That this singular report was both unpublished and biased is reason enough for further inquiry. Hence, the above-mentioned study is a long-awaited scientific foray into the realm of food and dreams.
The study itself used a variety of questionnaires aimed at assessing food-dependent dreaming, along with general sleeping, eating, and dreaming experiences in 396 first-year Canadian University students averaging 21.5 years of age. A three-item open-ended questionnaire was used to specifically probe participants’ beliefs of whether certain foods influence dreaming. The first question asked whether participants had ever noticed food leading to disturbing dreams, and, if so, to identify which foods, while the second question asked about bizarre dreams. The third question asked participants whether eating late at night had ever affected their dreams, and if so, how.
The authors found that 68 of 382 participants (17.8 percent) claimed that either particular foods or eating late at night influenced their dreams. Of those who believed food could influence dreams, the most frequent foods mentioned as causing both disturbing (44 percent) and bizarre (39 percent) dreams were, in fact, dairy, including cheese, milk, and ice cream. Spicy foods were the next most commonly mentioned as causing disturbing dreams (19 percent), though sweet foods were associated more with bizarre (27 percent) than disturbing dreams (13 percent). Further, 26 subjects reported that eating late affected dreaming; eating late was most commonly associated with disturbing or nightmarish dreams (47.2 percent), but was also associated with bizarre dreams (22.2 percent).
What this all boils down to, it would seem, is that a spicy cheese dish before bedtime could be the perfect recipe for a nightmare, just as illustrated by the comic. Could Welsh rarebit be a fiend after all?
The authors are more cautious in interpreting their results. In lieu of over-speculation, they provide several possible explanations for their findings and encourage future lab-based research to more stringently assess causal links between food consumption and dream content.
The most tempting interpretation, of course, is that food really does impact dreaming. This is perfectly reasonable when you consider that the nutrients in food can affect many things, such as mood or alertness during the day, or even sleep quality at night. In this case, the changes would most likely be of a general nature—perhaps increases in dream affect or vividness—due to general effects of food on mood and cognition. If a dash of cayenne pepper can perk you up after a meal, why shouldn't it also affect your dreams?
A related possibility is that food influences dreams indirectly due to poor metabolism or digestive intolerances. For instance, eating too late at night could negatively affect metabolism and sleep quality, thence seeping into your dreams. And, of course, dairy, most often cited as altering dreams, is a very common dietary sensitivity. Perhaps that bad dream is really just an upset stomach yelling at you to wake up.
On the other hand, the perceived link between food and dreams may actually be a false belief held by people, perhaps due to long-standing cultural folklore. These beliefs could be reinforced by individuals misattributing their own bizarre and disturbing dreams to food. For example, if local folklore says that pizza will give me nightmares, and one morning after having eaten pizza I awaken with a nightmare, I will more likely attribute that nightmare to having eaten pizza. Further, people are more likely to remember what they ate if it was close to bedtime, so eating late may increase chances of misattributing dream experiences to food.
Thus, while the authors did find evidence that people believe food can instigate bizarre or disturbing dreams, most commonly accusing dairy, whether these dreams are indeed caused by "the power of cheese," or simply misheld beliefs, remains to be seen.
Nielsen, Tore & Powell, Russell A. (2015). Dreams of the rarebit fiend: Food and diet as instigators of bizarre and disturbing dreams. Frontiers in Psychology, 6.