Ongoing research into the effects of alcohol on our bodies reveals a variety of different, sometimes contradictory, findings. But a constant appears to be emerging - that alcohol consumed in absolute moderation, may actually help, rather than harm, our health.
Researchers from the Massachusetts General Hospital (MGH) and Brigham and Women's Hospital (BWH) in the US assessed data from the Nurses' Health Study II and published their findings in the 11 March Archives of Internal Medicine.
"For women in their 20s to 40s, we found that alcohol intake at moderate levels was beneficial to blood pressure and at high levels it was harmful," said Ravi Thadhani of the Renal Unit at MGH and the Channing Laboratory at BWH, the paper's lead author.
Thadhani and his colleagues found that the association between alcohol consumption and risk of chronic hypertension in young women follows what is called a J-shaped curve: light drinkers had a decreased risk compared with non-drinkers, but heavier drinkers had an increased risk.
Thadhani and his team gathered data from over 70,000 women aged 25 to 42 years old at the study's outset in 1989, who did not report having hypertension during the study's early years. After eight years of follow-up, the scientists found that women who drank about two or three drinks a week had a risk of developing hypertension about 15 per cent lower than that of non-drinkers. However, women who drank on average more than 10 or 12 drinks per week had a 30 per cent increased risk of developing the condition.
The study also looked at patterns of alcohol consumption. "We found that episodic or binge drinking didn't increase the risk of high blood pressure compared to drinking more regularly," said Thadhani. But he cautioned that binge drinking is associated with stroke, cardiovascular disease and trauma.
Thadhani and his colleagues also investigated whether there were any differences in the type of drink consumed. At the higher levels of consumption, all beverages - beer, wine and spirits - increased blood pressure, whereas there was a suggestion that moderate beer drinking led to lower blood pressures. The researchers noted that more work needs to be done on this area.
"This study suggests that drinking moderate amounts of alcohol may be one way to modify a woman's risk of developing high blood pressure," said Thadhani. He stressed the importance of maintaining a healthy blood pressure because chronic hypertension is associated with heart attack, stroke, and kidney disease. "Our next step is to understand how alcohol effects women of different races and ethnicity, since one group may respond differently to another. We also want to see if modifying alcohol consumption can help women who already have high blood pressure get to a healthier level," said Thadhani.