What Drinking Coffee Every Day Does to You

This piece, by Onno Berkan, was published on 01/21/25. The original text, by Magalhães et al., was published by Nature Molecular Psychiatry on 04/20/21.

This University of Minho study examined how regular coffee consumption affects the brain's functional networks and connectivity patterns. Coffee is the world's most widely consumed source of caffeine, with many people consuming it multiple times daily, yet its long-term effects on brain function were largely unknown before this research.

The researchers divided participants into two groups:

• Coffee drinkers (CD): People who drank at least one cup of caffeinated coffee daily

• Non-coffee drinkers (NCD): People who drank less than one cup per week

All participants were asked to avoid caffeine for three hours before the study to prevent immediate caffeine effects. The researchers used functional magnetic resonance imaging (fMRI) to examine brain activity patterns while participants were at rest and also assessed their stress, anxiety, and depression levels.

Key findings revealed that regular coffee drinkers showed:

1. Decreased connectivity in specific brain networks:

• The somatosensory network (involved in processing sensory information)

• The limbic network (involved in emotional processing)

These changes correlated with how frequently people consumed caffeinated products.

2. A distinct pattern in brain regions associated with:

• Motor control

• Visual processing

• Memory

• Attention

These differences suggest coffee drinkers may have enhanced alertness and readiness for sensory perception.

Interestingly, when non-coffee drinkers were given a single cup of coffee, their brain patterns temporarily changed to resemble those of habitual coffee drinkers. This suggests a potential direct causal relationship between coffee consumption and these brain connectivity changes.

Regarding psychological effects, the study found that:

• Coffee drinkers showed higher stress levels than non-coffee drinkers

• Increased caffeine consumption was associated with higher anxiety levels in males specifically.

The obvious objection here is that coffee drinkers consume so much caffeine because they’re stressed, rather than the coffee making them stressed. While we don’t know what came first, the researchers did discover a clear correlation between caffeine consumption and stress levels.

On the other hand, the researchers noted that these brain connectivity changes might actually be beneficial, potentially leading to:

• More efficient motor control

• Enhanced alertness

• Improved visual processing

• Better memory processes,

The study also revealed that caffeine's effects involve multiple brain regions, particularly those with high densities of specific receptors (A2A and A1) that caffeine interacts with. This helps explain why coffee affects various aspects of brain function, from alertness to emotional processing.

Overall, the study represents the first comprehensive examination of how regular coffee consumption affects human brain networks. While it may not be as harmful as other substances, not drinking coffee every day may be the way to go.

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