💊 The placebo produces a new very unexpected effect

A recent experiment shows that elderly volunteers who ingested placebo capsules for three weeks recorded measurable improvements in memory, physical performance, and well-being. This observation highlights the influence of the mind on the body as we age.

To study the mechanisms, researchers from the Università Cattolica of Milan recruited 90 healthy older adults and divided them into three groups. The first group received no intervention. The second received placebos presented as active supplements. The third received open-label placebos, meaning participants were informed of their inactive nature but were told that the placebo effect could still work. The study was published in the International Journal of Clinical and Health Psychology.


Before and after the three-week intervention, participants completed questionnaires on perceived stress, psychological well-being, drowsiness, fatigue, optimism, self-efficacy, and their beliefs about aging. They also took objective tests of short-term memory, selective attention, and physical performance. The results showed notable differences between the groups.

The group that knowingly took a placebo reported lower stress levels than the other two groups. Their short-term memory also improved significantly compared to the control group. Both placebo groups showed cognitive and physical benefits, but the strongest effects were generally seen in those who knew they were taking a placebo. Physical performance increased by 7% with the deceptive placebo and by 9.2% with the open-label placebo.

These improvements are comparable to those observed in studies on physical activity or cognitive training, according to the researchers. The study indicates that placebo interventions can improve several aspects of functioning in older adults. Open-label placebos, in particular, offer an ethical and effective option to support healthy aging without deception.

According to Professor Pagnini, these results add to the evidence that mental factors such as thoughts, emotions, and self-perception play an important role in aging. Their influence is not limited to psychological well-being but also affects physical and cognitive functions. Thus, simply expecting benefits could help slow down some effects of aging.

The placebo effect: the power of belief

The placebo effect refers to the improvement of a patient's symptoms after receiving an inactive treatment, simply because the patient believes they are receiving a real treatment. This phenomenon is well known in medical research, where a new drug is often compared to a placebo to measure its true efficacy. The underlying mechanisms are complex and involve psychological and neurobiological processes.

Expectations play a key role: if a person expects to feel relief, their brain may release endorphins or modulate neurotransmitter activity. Conditioned learning, cultural beliefs, and the relationship with the caregiver also influence this effect. In the study on seniors, even when knowing the pill was inactive, participants benefited from the placebo effect, indicating that positive expectations remain active.

It is important to note that the placebo effect does not cure the underlying cause of a disease, but it can improve subjective symptoms such as pain, anxiety, or fatigue.

Finally, the placebo effect does not work for everyone and can be influenced by personality, emotional state, or genetics. Ongoing studies aim to better understand which patients are most receptive and how to optimize placebo interventions in a clinical setting.