- It has been reported that consuming caffeine may reduce task performance related to spatial memory.
- The evidence score is 39, indicating that reliability is shown to be limited (low).
- The study covers people who habitually drink coffee or tea.
Coffee is a beverage made from coffee beans.
It is classified as a beverage consumed for pleasure, and is widely consumed as an everyday habit.
It has been suggested that caffeine intake may affect the ability to retain spatial information. This refers to the ability to temporarily hold information such as places and locations in the brain.
In this study, a very small group of 18 people who habitually drink coffee or tea participated. The study examined what changes occur in this group when they consume 200mg of caffeine. In other words, this was an investigation into how habitual caffeine intake relates to a specific brain function.
Technically, a randomized controlled trial (a reliable research method in which participants are randomly divided to compare effects) was used. This method is very important for confirming that the results are not due to chance. In other words, a standard procedure was followed to increase the accuracy of the data.
This study was a small-scale study conducted with an extremely small number of participants — just 18 people. Several measures were built into the study design.
In the experiment, participants were divided into a group that consumed caffeine and a group that did not. A double-blind method (a method in which neither the experimenters nor the participants know which substance was consumed) was used, so that neither the researchers nor the participants knew who had actually consumed caffeine. This is a mechanism for removing the influence of assumptions or preconceptions. In other words, it was a setup designed to observe purely the changes caused by the ingredient.
The comparison was made against a caffeine-free placebo (a fake substance that has no actual active ingredient but looks the same as the real thing). By strictly matching the conditions in this way, the study attempted to measure the effect of caffeine itself. In other words, this is a measure taken to maintain the fairness of the experiment.
The findings obtained from this study's results must, at this point, be considered limited. The content reported is confined to the effect on the specific ability known as "spatial working memory."
Looking at the evidence score, which is an indicator of data reliability, a value of 39 is shown. This means reliability is low, and it is difficult to judge everything based on the results of this single study alone. In other words, this can be said to be a stage where much more verification is still needed.
It should also be considered that the participants were habitual caffeine consumers. Whether the exact same phenomenon would occur in people who do not usually drink much caffeine is not known from this data. In other words, this leaves open the possibility that results may differ depending on an individual's lifestyle.
| Study | Design | Number of participants | Duration | Main result |
|---|---|---|---|---|
| Clinical Nutrition ESPEN (2024, PMID:39244155) | Randomized controlled trial (RCT) | 18 | Unknown | A possible negative effect was reported |
The study subjects were 18 habitual caffeine consumers.
Since the subjects were habitual consumers, this can serve as a reference point for people who drink coffee and similar beverages on a daily basis to consider whether it applies to them.
Since there is only one study, caution is needed in drawing many conclusions from this report.
The study design is a randomized controlled trial (RCT), but reliability is reported to be limited.
Please note that this result applies to specific conditions and may not apply to every situation.
Does drinking coffee affect cognitive function?
It has been reported that, in habitual caffeine consumers, there may be a negative effect on cognitive performance. This result is based on a single report.
Does the caffeine in coffee affect memory?
It has been suggested that consuming 200mg of caffeine may reduce spatial working memory. This is a result from a study of habitual caffeine consumers.
How reliable is this research on coffee?
Reliability is reported to be limited.
One study has reported that a component of coffee may affect the retention of spatial information. However, since the study scale is small and reliability is limited, avoid making judgments based on this result alone. If you notice a change in your own concentration, it may be a good idea to reflect on it using the self-check assessment.