EFSA rejects coffee’s DNA damage-reducing claim

Writing in its official journal​​, the European Food and Safety Authority (EFSA), concluded that claims put forward by German coffee retailers Tchibo could not be proved by submitted scientific evidence.

“In weighing the evidence, the Panel takes into account one study that provides evidence that daily consumption of Coffee C21 (750 mL/day) for 4 weeks decreases DNA strand breaks in habitual coffee drinkers after coffee withdrawal over the previous 4 weeks,”​ said EFSA.

“However, the results of this study were not replicated in another study conducted under similar conditions in the same study centre. ​

“There are no studies performed in a different setting, from which conclusions could be drawn that are available. ​

“The Panel also takes into account that no evidence has been provided for a mechanism by which coffee (including Coffee C21) would protect DNA from strand breaks.”​

Consumed as beverage​

According to Tchibo, Coffee C21 contains 10.18 milligrams per gram (mg/g) of caffeoylquinic acids (CQA), 3.82 mg/g of trigonelline and 1.10 mg/g of N‐methylpyridinium (NMP), to be consumed as a beverage.

Tchibo also claimed that ‘intense roasting of coffee enhances the ability of coffee extracts to upregulate the nuclear factor erythroid 2‐related factor 2 (Nrf2), a regulator of genes responsible for cell defence and repair.’

Coffee C21 was said to exert its action via a direct pathway – scavenging of free radicals by antioxidants in dark roast coffee, or by indirect means - activation of endogenous protective responses via modulation of gene expression.

Other details of the application focus on the target group as the ‘general population, which drinks coffee’.

“The daily consumption of two to three large cups (in total 500–750 millilitres (mL)) over the day is recommended by the applicant to obtain the claimed effect,”​ Tchibo said.

DNA strand breaks occur spontaneously during the DNA repair process but can also be induced by, e.g. environmental factors (such as mutagenic or pro‐oxidant chemicals, radiation).

Such DNA strand breaks alter DNA properties, may induce anomalies during DNA replication and translation and require repair for maintenance of cell functioning and survival.

Research assessment​

Out of the two human intervention studies from which conclusions could be drawn, one study provided some evidence that daily consumption of Coffee C21 (750 mL/day) for 4 weeks decreases DNA strand breaks in habitual coffee drinkers after coffee withdrawal over the previous four weeks.

However, the results of this study were not replicated in another study conducted under similar conditions in the same study centre.

“No studies performed in a different setting, from which conclusions could be drawn, were available,”​ the Panel concluded.

“No evidence has been provided for a mechanism by which coffee (including Coffee C21) would reduce DNA damage in human cells by reducing DNA strand breaks.”​

“The Panel concludes that a cause and effect relationship has not been established between the consumption of Coffee C21 and protection of DNA from strand breaks.”​