According to biochemical research, what has not yet been proven in practise is at least very plausible. The team, led by chemist Professor Nikolai Kuhnert and including Dorothea Schmidt and Nicholas Ohl of Jacobs University, was able to demonstrate experimentally—in the laboratory—that the chemical compound 5-caffeoylquinic acid (trivial name: chlorogenic acid), found in coffee, inhibits the interaction of the SARS CoV-2 spike protein of the coronavirus and the ACE-2 receptor, the virus's docking site on the human cell, by a factor of
A regular cup of filter coffee—exactly 200 millilitres in the laboratory—contains about 100 milligrammes of 5-caffeoylquinic acid. Experiments in the lab revealed that 5-caffeoylquinic acid at this concentration is strong enough to prevent the spike protein from docking to the ACE-2 receptor, thereby inhibiting the infection process. More research is needed to demonstrate that this process works in practise.
Further research will be required to determine how long the inhibitory effect of 5-caffeoylquinic acid will last. "We cannot answer the practical question of whether drinking coffee can truly serve as a preventive measure against infection as chemists. However, we can state that it is plausible "Kuhnert stated. "Many people drink coffee, and it is well established that it has many other positive effects," says the chemist. He points out that regular coffee drinkers are less likely to develop type II diabetes.
The team led by Nikolai Kuhnert had to develop a new measurement technique for their studies on the effect of 5-caffeoylquinic acid on the spike protein and ACE-2 receptor: differential scanning fluorimetry, or nano-DSF. This method was recently described in detail by the team in the journal Food & Function. The findings on the interaction of coffee and the coronavirus will now be shared with the larger research community. "Epidemiological studies could determine whether or not regular coffee drinkers are more likely to become infected with corona," says Nikolai Kuhnert. The context and implications for long COVID could also be considered here.