Visiting the fridge at night for a quick midnight snack is not only hurting your fitness goals but also your brain health. Apparently, eating midnight snacks can impair your memory, according to researchers from Semel Institute at the David Geffen School of Medicine at the University of California Los Angeles (UCLA).

The researchers, working on the premise that disrupted eating times can have a negative effect on metabolic health, investigated if the same practice also affected cognitive health. They conducted an experiment on mice and found out that snacking late at night - during hours that are supposed to be for sleeping - harms the mice's memory, particularly impacting their brain's hippocampus.

Although the study has not been conducted in humans, the researchers emphasized that people who work on shifts generally do not perform as well as others on cognitive tests.

"We have provided the first evidence that taking regular meals at the wrong time of day has far-reaching effects for learning and memory," lead study author Dawn Loh from the UCLA Laboratory of Circadian and Sleep Medicine, said in a press release. "Since many people find themselves working or playing during times when they'd normally be asleep, it is important to know that this could dull some of the functions of the brain."

In the study, the researchers observed that mice's ability to recognize an object was impaired when they were fed at times when they normally slept. Their long-term memory was also affected. These two functions - recognizing objects and long-term memory - are both controlled by the hippocampus.

However, the researchers found that the suprachiasmatic nucleus in the hypothalamus, which controls the circadian rhythm, was not at all affected. The researchers suggested that this misalignment in the body's internal clocks caused a damage in the memory.

"Modern schedules can lead us to eat around the clock so it is important to understand how the timing of food can impact cogitation," study coauthor Christopher Colwell, professor from the Department of Psychiatry and Biobehavioral Sciences at UCLA, said. "For the first time, we have shown that simply adjusting the time when food is made available alters the molecular clock in the hippocampus and can alter the cognitive performance of mice."

The study was published Dec. 23 in the journal eLife.