As part of the study researchers asked 100 college students to rate their favourite comfort foods.
They then induced a bad mood in the students by making them watch clips from sad films.
They then fed half the students their favourite comfort foods, and the other half ate foods they enjoyed but wouldn't consider comfort food.
Once the students had finished eating, the researchers asked the students how they felt. It turns out all the students felt better, regardless of what they had eaten.
They repeated the same experiment except this time, half the students ate comfort food, and the other half ate nothing.
After a few minutes, both groups felt equally better and researchers said the comfort food had no effect on mood.
Writing in the report, lead researcher Traci Mann, of the University of Minnesota said: "Although people believe that comfort foods provide them with mood benefits, comfort foods do not provide comfort beyond that of other foods (or no food).
"Individuals may be giving comfort food "credit" for mood effects that would have occurred even in the absence of the comfort food."
Researchers admitted the study had significant limitations, one of which being that it only looked at a particular type of 'bad mood' - induced by watching sad films.
They added they didn't look at the real-life contexts in which people eat comfort foods, and said perhaps the comfort from comfort food comes from going to a cafe and acquiring it.
However they said they weren't surprised by the findings as changes in mood are psychological, with food a very weak trigger for changes.
David Levitsky, a professor of nutrition at Cornell University told NPR: 'We tend to look for a magic solution to our problems.
"The idea we can feel better by simply consuming certain foods is very appealing but in actuality, feeling better has nothing to do with the food itself, and it's a very weak psychological effect."
He added that we don't necessarily need to step away from ice-cream and pizza when we feel sad.
"There's no harm to it, unless you're overeating, or consistently eating food to avoid coping with big problems," he said.
The study was published in Health Psychology journal.
- Daily Mail