Il caffè può essere liberamente inserito in uno stile alimentare salutare. Lo conferma quest’analisi, basata sui due corposi e ben noti studi americani di popolazione, condotti sulle infermiere (Nurses’ health Study 1 e 2) e su professionisti della salute (Health Professionals’ Follow-up Study), che fornisce un solido contributo alla definizione delle proprietà positive della bevanda più diffusa al mondo.
Il consumo moderato e quotidiano di caffè (fino a 5 tazze/die) sia con caffeina, sia decaffeinato, si associa infatti a una riduzione della mortalità totale, valutata sul complesso delle popolazioni studiate. Una volta scorporata però la quota di soggetti non fumatori, l’associazione tra consumo abituale di caffè e mortalità totale si delinea meglio. In coloro che non fumano, infatti, al crescere del consumo di caffè (da meno di 1 tazza a 5 tazze al giorno e più) corrisponde una progressiva riduzione della mortalità totale, significativa per le cause cardiovascolari e neurologiche e per il rischio suicidario.
La mancanza di differenze associate all’assunzione di caffeina porta gli autori a ipotizzare che i benefici possano essere attribuiti ad altri componenti minori del caffè (comuni al caffè vero e proprio e al decaffeinato), come l’acido clorogenico, i lignani e il magnesio, con potenziali effetti positivi sull’insulinoresistenza e sull’infiammazione sistemica.
Coffee & health: The association between consumption of caffeinated and decaffeinated coffee and risk of mortality remains inconclusive
We examined the associations of consumption of total, caffeinated, and decaffeinated coffee with risk of subsequent total and cause-specific mortality among 74,890 women in the Nurses’ Health Study (NHS), 93,054 women in the NHS 2, and 40,557 men in the Health Professionals Follow-up Study. Coffee consumption was assessed at baseline using a semi-quantitative food frequency questionnaire. During 4,690,072 person-years of follow-up, 19,524 women and 12,432 men died. Consumption of total, caffeinated, and decaffeinated coffee were non-linearly associated with mortality.
Compared to non-drinkers, coffee consumption one to five cups/d was associated with lower risk of mortality, while coffee consumption more than five cups/d was not associated with risk of mortality. However, when restricting to never smokers, compared to non-drinkers, the HRs of mortality were 0.94 (0.89 to 0.99) for ≤ 1 cup/d, 0.92 (0.87 to 0.97) for 1.1-3 cups/d, 0.85 (0.79 to 0.92) for 3.1-5 cups/d, and 0.88 (0.78 to 0.99) for > 5 cups/d (p for non-linearity = 0.32; p for trend < 0.001). Significant inverse associations were observed for caffeinated (p for trend < 0.001) and decaffeinated coffee (p for trend = 0.022). Significant inverse associations were observed between coffee consumption and deaths due to cardiovascular disease, neurological diseases, and suicide. No significant association between coffee consumption and total cancer mortality was found.
CONCLUSIONS: Higher consumption of total coffee, caffeinated coffee, and decaffeinated coffee was associated with lower risk of total mortality.
