Coffee can protect the nervous system

Coffee helps protect the nervous system, thanks to the synergy of the phytocompounds that characterize it. To these conclusions comes a meta-analysis of scientific publications of the last 10 years, conducted at the University of Porto (Carneiro et al., 2021).

The neuroprotective action of the numerous bioactive compounds, among the over a thousand phytocompounds present in coffee, has also been demonstrated in vivo. And the researchers suggest conducting new studies on its possible contribution to treating degenerative diseases. (1)

Coffee. Botany, flavor and health

The coffee plant belongs to the genus Coffea and is characterized by more than 70 different species. However, only two of them are grown to produce the drink of the same name, Coffea arabica (Arabica variety) e Coffea canephora (Robusta variety). The crops are located in the so-called ‘coffee belt’, between the latitudes of 20 ° north and 20 ° south of the equator. This band includes about 80 countries in Africa, Asia, Central and South America. (2)

The origin and the transformation of coffee have decisive influences on flavor and aroma, due to the different native chemical composition of the seeds and the changes that occur following roasting. Which in turn contributes to the availability of biocompounds which are also appreciated for the associated health benefits. The progressive diffusion of green coffee consumption (not roasted) is attributed, among other things, to the prospect of a greater contribution of phytocompounds of health importance. (3)

Caffeine and other alkaloids

Caffeine – alkaloid ‘par excellence’ in coffee – stimulates the central nervous system (CNS) by triggering competition with adenosine, which instead inhibits some neurotransmitters and promotes sleep. And it is precisely the function of contributing to improving mood and attention that has made coffee, over the centuries, one of the most popular drinks on the planet. (4)

The trigonellina it is the second most important alkaloid in coffee seeds, where it is transferred from the fruits where it is formed. And it is able to associate a hypoglycemic action with the protection of neurons, also favoring an improvement in memory capacity. (5) Theobromine and theophylline – other alkaloids present in coffee, as well as in cocoa and tea – are instead involved to a limited extent in the interaction with the CNS, due to the low concentration in the drink. (6)

Polyphenols and other compounds

Numerous phenols and their compounds, also present in coffee, contribute to efficiency and the proper functioning of the nervous system. Polyphenols – and phenolic acids in particular – are the most important substances, together with alkaloids. Although various others are able to contribute, in various respects, to this important benefit. (7) Of particular note:

– caffeic acid, ferulic acid and chlorogenic acid. Phenolic acids with antioxidant and anti-inflammatory properties,

– melanoidins. Products from the roasting of coffee, they are responsible for the dark color of the coffee and contribute to the peculiar aroma. They possess antioxidant and anti-inflammatory properties,

– serotonin. The so-called ‘happiness hormone’ is involved in improving cognitive functions,

– tocopherols. The class of substances to which vitamin E belongs, helps to counteract free radicals,

– polysaccharides. A class of its own, useful for stimulating the development of the intestinal microbiota and the functioning of the brain-intestine axis, as we have seen.

Coffee and neurodegenerative diseases

Neurodegenerative diseases they originate from the aging or death of neurons, status which progressively advance and occur more frequently in old age. Thanks to the contribution of coffee and caffeine (in primis), it is estimated the possibility of slowing the onset and manifestation of diseases such as Alzheimer’s, Parkinson’s, ALS (amyotrophic lateral sclerosis), multiple sclerosis, dementia with Lewy bodies and Huntington’s disease.

In fact, in numerous scientific studies clinicians have proven that the protective effect on these diseases is due to the synergistic action of the set of substances present in coffee, as caffeine is not in itself capable of providing adequate neuroprotection. Even if it plays a fundamental role since decaffeinated coffee, while having good properties, is less effective than conventional coffee.

Health claims, taboo at the bottom of the cup

EFSA (European Food Safety Authority) validated in 2011 the scientific substantiation of the correlations between the contributions of coffee and its components and the various health benefits listed below:

– the increase in resistance e performance during sports exercise it is associated with the intake of caffeine at the rate of 3 mg / kg of body weight of caffeine, one hour before activities. (8)

– the increased state of alertness and attention is associated with the consumption of coffee with a concentration of at least 75 mg of caffeine per cup, by adults only. (9)

The European Commission however, in the past ten years, it has failed to pronounce on the authorization of the relative health claim. The taboo goes beyond the correct application of the reg. CE 1924/06, in the general indifference.

Provisional conclusions

Despite the taboos in Brussels, EFSA has recognized that moderate consumption of coffee, around 3-4 cups a day, can bring various health benefits (EFSA). However, these news should be considered carefully, taking into account the sensitivity of each individual to caffeine. (10)

Further research are necessary to evaluate more precisely the possible benefits of coffee and its components, with particular regard to neuroprotection activities. (11)

Dario Dongo and Andrea Adelmo Della Penna

Footnotes

(1) Carneiro et al. (2021). Neuroprotective properties of coffee: An update. Trends in Food Science & Technology 113: 167-179, 

(2) Zhu et al. (2021). Comparison of chemical and fatty acid composition of green coffee bean (Coffea arabica L.) from different geographical origins. LWT – Food Science and Technology 140: 110882, 

(3) Ciaramelli et al. (2019). Coffee variety, origin and extraction procedure: Implications for coffee beneficial effects on human health. Food Chemistry 278: 47-55, 

(4) Clark et al. (2017). Coffee, caffeine, and sleep: A systematic review of epidemiological studies and randomized controlled trials. Sleep Medicine Review 31: 70-78, 

(5) Hu et al. (2019). The sources and mechanisms of bioactive ingredients in coffee. Food & Function 10: 3113-3126, 

(6) Singh et al. (2018). Xanthine scaffolds: scope and potential in drug development. Helyon 4: e00829, 

(7)Ludwig et al. (2014). Coffee: biochemistry and potential impact on health. Food & Function 5: 1695-1717, 

(8) EFSA NDA Panel (2011). Scientific Opinion on the substantiation of health claims related to caffeine and increase in physical performance during short-term high-intensity exercise (ID 737, 1486, 1489), increase in endurance performance (ID 737, 1486), increase in endurance capacity (ID 1488) and reduction in the rated perceived exertion / effort during exercise (ID 1488, 1490) pursuant to Article 13 (1) of Regulation (EC) No 1924/2006. EFSA Journal 9 (4): 2053. 

(9) EFSA NDA Panel (2011). Scientific Opinion on the substantiation of health claims related to caffeine and increased fat oxidation leading to a reduction in body fat mass (ID 735, 1484), increased energy expenditure leading to a reduction in body weight (ID 1487), increased alertness (ID 736 , 1101, 1187, 1485, 1491, 2063, 2103) and increased attention (ID 736, 1485, 1491, 2375) pursuant to Article 13 (1) of Regulation (EC) No 1924/2006. EFSA Journal 9 (4): 2054, 

(10) EFSA NDA Panel (2015). Scientific Opinion on the safety of caffeine. EFSA Journal 13 (5): 4102, 

(11) Kim, JW, Byun, MS, Yi, D. et al. (2019). Coffee intake and decreased amyloid pathology in human brain. Transl Psychiatry 9, 270.