Short answer: Yes. A randomized controlled trial found that older adults who watched a humorous video performed measurably better on memory tests than those who didn’t, alongside significantly lower levels of the stress hormone cortisol. The proposed mechanism is straightforward: laughter appears to reduce a hormone known to interfere with memory formation.
What the Research Actually Found
The most directly relevant study on this question comes from researchers at Loma Linda University, published in the journal Advances in Mind-Body Medicine and available via PubMed. The research team designed a randomized controlled trial involving healthy older adults and older adults with type 2 diabetes. Participants in the humor groups watched a 20-minute funny video, choosing between a classic Red Skelton comedy routine or a compilation of America’s Funniest Home Videos, while a control group sat quietly without any humor stimulus. All participants then completed memory tests and had their cortisol levels measured through saliva samples.
The results were notable. Learning ability improved by 38.5 percent in the healthy humor group and 33.4 percent in the diabetic humor group, compared to just 24.0 percent in the control group. The humor groups also showed statistically significant decreases in salivary cortisol at multiple points during the study, while the control group showed no significant cortisol changes at all. Study co-author Dr. Lee Berk, a long-time researcher in psychoneuroimmunology, explained the underlying logic in comments reported by ScienceDaily: chronically elevated cortisol is known to damage neurons in the hippocampus, the brain region central to learning and memory, so reducing cortisol through laughter may help protect this process, particularly in older adults who are more vulnerable to stress-related memory decline.
Beyond this specific memory finding, laughter appears to produce several other measurable brain effects. According to Northwell Health, a study published in the Journal of Neuroscience used PET scans to examine participants’ brains after they watched comedy clips with close friends, finding that social laughter increased the brain’s production of endorphins and triggered measurable opioid release, along with elevated pain thresholds. Laughter also increases blood flow to the brain, which researchers note may support broader brain health and is separately linked to reduced risk of cognitive impairment.
It’s worth being appropriately cautious about the scope of this evidence. The Loma Linda study, while a genuine randomized controlled trial, involved a relatively small sample of 30 total participants, which is a meaningful limitation. Some broader reviews of laughter research have also noted that much of the wider literature on humor’s health benefits relies on self-report measures rather than controlled, objective testing, meaning the field would benefit from more studies of this same rigorous design. Still, the cortisol-and-memory mechanism identified here is biologically well-grounded and consistent with well-established, independent research on how chronic stress hormones affect the hippocampus.
How to Put This Into Practice
- Build in genuine laughter, not just amusement. The strongest evidence involves real, sustained laughter, not simply passive entertainment.
- Social laughter may add extra benefit. The endorphin-related findings specifically involved laughing with close friends, suggesting a social component may amplify the effect.
- Consider it a genuine stress-management tool, not just a mood booster. Since the mechanism runs through cortisol reduction, laughter functions similarly to other evidence-based stress-reduction strategies.
- It’s a complement, not a substitute. Laughter’s cognitive benefits work best alongside other established brain health habits like sleep, exercise, and social connection, not as a replacement for them.
So “laughter is the best medicine” turns out to have a real, measurable basis in the research, at least when it comes to memory and the stress hormone that can quietly undermine it over time.
