Alcohol douses the blood pressure benefit of red wine
medwireNews: Alcohol-free red wine is more effective at lowering blood pressure (BP) than traditional red wine or gin, a study shows.
This finding provides a new insight into the role of dietary components, such as red wine polyphenols, in cardiovascular (CV) health and suggests that consumption of alcohol-free red wine might be useful in preventing low- to moderate-degree hypertension, say Ramon Estruch (Hospital Clinic Vilarroel, Barcelona, Spain) and team.
They found that men with diabetes or three or more CV risk factors who were randomly allocated to consume 272 mL of traditional red wine each day in addition to their normal diet for 4 weeks experienced a small reduction in systolic and diastolic BP (2.3 and 1.0 mmHg reductions, respectively).
However, men who were assigned to consume 272 mL of dealcoholized red wine each day for 4 weeks experienced a significant 6 mmHg reduction in systolic BP and a 2 mmHg reduction in diastolic BP "possibly reducing the risk of heart disease by 14% and stroke by as much as 20%," remark the authors.
Systolic BP decreased by only 0.8 mmHg and diastolic BP actually increased by 0.1 mmHg after the gin intervention.
The researchers attribute the change in BP with dealcoholized wine to increased levels of nitric oxide (NO), which helps blood vessels relax and decreases BP, they explain.
Indeed, plasma NO was increased by 4.1 µmol/L in participants after drinking dealcoholized red wine for 4 weeks, compared with only 0.6 µmol/L after the traditional red wine phase, and a decrease of 1.4 µmol/L after the gin phase.
The researchers conclude that the alcohol in red wine weakens its ability to lower BP. They note that polyphenols, which were present in equal quantities in the dealcoholized and the traditional red wine, are likely to be the cause of red wine's BP-lowering effect.
By Piriya Mahendra, medwireNews Reporter