Could your daily espresso turn out to be a functional food that protects your brain from Alzheimer’s disease? In a recent study published by the University of Verona, Italy (Tira et al. 2023), the authors considered whether some of the compounds found in espresso could act against the abnormal formation of tau proteins in the brain. The accumulation of these proteins is thought to play an essential role in neurodegenerative disorders such as dementia and Parkinson’s disease.
Given that there are currently no effective treatments, it’s worth investigating these and other compounds to see whether they can prevent or at least slow down the progression of these brain disorders. Who would have thought espresso could be so good for you?
What are tau proteins, and what’s all the fuss about them in the brain?
Tau is a protein in the cells of all kinds of creatures, from humans to insects. It’s predominantly found in neurons in the brain. Tau has been implicated in a number of neurodegenerative diseases (called tauopathies), including some frontotemporal dementias, repeated traumatic brain injuries, Alzheimer’s, and Parkinson’s.
To understand why, we need to understand the role of tau proteins within neurons.
Nutrients and other molecules travel from one end of the neuron to the other through structures called microtubules. Tau proteins help to stabilize these structures by binding them. When these proteins undergo certain chemical changes, they detach from the microtubles and aggregate (stick to other tau proteins within the cell) to form tangles.
Over time, these tangles can block the neuron’s ability to function and communicate, leading to neuronal damage and death. These tangles can spread to other neruons and accumulate in many areas of the brain. This results in further loss of neuronal function and the manifestation of neurodegenerative diseases, including those involving memory loss.
The Espresso Study
Espressos were extracted and brewed in different concentrations using Arabica and Robusta coffee beans, and then profiled for their compounds. Once these compounds were identified, caffeine, trigonelline, and genistein were isolated. The researchers conducted various laboratory tests to investigate the behavior and impact of these compounds on tau proteins and the formation of tau fibrils into clumps.
Tests showed that some of the compounds in espresso coffee extract could decrease tau aggregation. The effects varied with the concentration of coffee used. They also showed that these compounds could interfere in the early stages of the tau formation process. It seems that caffeine and genistein were the most promising compounds, with caffeine showing a significant ability to inhibit tau aggregation.
What does this mean for you?
The authors of the paper note that moderate consumption of two to three cups of espresso per day (based on a 40 ml cup) may exert a neuroprotective effect when it comes to the formation and aggregation of tau proteins.
But before you decide to up your espresso consumption in the hopes of preventing neurodegenerative disease. You should know that this study was exploratory in nature. More research is required to understand whether and how this translates into a health benefit.
In the meantime, there’s good reason to continue enjoying that daily espresso shot!
