Chocolate cuts blood pressure

Dark chocolate and cocoa products which are rich in a group of chemicals called flavanols may reduce blood pressure, a meta-analysis of 20 studies suggests.

The 856 volunteers, most of whom were healthy, ate 3.6-105g of cocoa products containing between 30 and 1080mg of flavanols (mean 545.5mg) daily for 2 to 18 weeks (mean 4.4 weeks). Controls ate products containing no or low levels of flavanols (6.4 or 41mg).

Flavanol-rich cocoa products reduced systolic and diastolic blood pressure by 2.77 and 2.20 mmHg respectively. Five per cent of people taking flavanol-rich products developed gastrointestinal or other adverse effects, or disliked the taste, compared to 1 per cent of controls. Further trials need to determine any long-term effects on blood pressure, whether cocoa products reduce cardiovascular events and to characterise side effects.