The press reported the findings uncritically, but close reading of the 567-page report reveals some bias in its assessment of the dangers of alcohol. Take colon cancer, for which, the report says, "there is ample and generally consistent evidence [that]
. . . a dose-response is apparent". How-ever, most of the studies cited showed that such a relationship was "non-significant", meaning that it was probably a chance finding and barely measurable.
As for kidney cancer, there is evidence that alcohol may actually prevent it, yet the report confusingly concludes: "It is unlikely that alcohol increases the risk of kidney cancer, though a protective effect cannot be excluded."
Regarding breast cancer, the report claims that the evidence of harm from alcohol is "convincing". But many of the studies cited had non-significant results and "high heterogeneity"-in other words, no clear pattern. Putting these caveats aside, the data suggest a 5-per-cent increase in breast cancer risk for every five drinks consumedper week (see box below).
For cancers of the mouth, throat, larynx and oesophagus, the increased risk is apparently smaller but, again, the data are somewhat patchy.
Although the authors condemn alcohol outright in the context of cancer, they recommend "no more than two drinks per day for a man,and no more than one for a woman". That's because, in the context of heart disease, alcohol is far from a demon drink, but appears instead to be a potent preventative.
In January 2006, Harvard University researcher Dr Joline Beulens reported the findings of a 16-year US study, in which she tracked the health of nearly 12,000 male health professionals at high risk of heart attack; all had hypertension, and many had been advised to stop drinking any alcohol because having even just one or two alcoholic drinks a day was thought to raise blood pressure.
To Dr Beulens' surprise, however, this turned out to be totally wrong-headed. Those who suffered heart attacks were mostly those who had gone teetotal. In fact, the fewest heart attacks were among the men who had completely flouted the doctors' orders. And in this case, the more they drank, the fewer the heart attacks. By the time the men reached an intake of more than 50 g/day of alcohol, their risk of a heart attack was more than halved (Ann Intern Med, 2007; 146: 10-9).
The reason is that alcohol appears to prevent atherosclerosis and reduce cholesterol, say German cardiologists, who have found that the patients who enjoyed at least one drink a day have far fewer blockages in their arteries (Heart, 2004; 90: 1189-93).
Here's to your health?
Alcohol may also help to prevent a litany of other diseases:
- Type 2 (non-insulin-dependent) dia-betes risk is reduced by 30 per cent if you drink 'moderately' whereas teetotalers and heavy drinkers are equally likely to develop the disease (Diabetes Care, 2005; 28: 719-25).
- Men who drink four to seven glasses of wine a week reduce their risk of prostate cancer by 52 per cent (Harvard Men's Health Watch, 2007; 11: 6-7).
- Just one glass of wine a day can reduce the risk of dementia by a staggering 85 per cent and, if you already are mildly cognitively im-paired, don't go teetotal (Neurology, 2007; 68: 1790-9). This is further supported by evidence from France, where regions with the highest wine consumption tended to have the least Alzheimer's sufferers (Presse Med, 2006; 35: 1309-16). It's thought that the resveratrol in red wine is what makes it so valuable.
On the other hand, alcohol can be a killer: cirrhosis of the liver is anobvious hazard, but it's rarer than its reputation. In fact, doctors are puzzled why so few heavy drinkers have it. For women fearful of breast cancer, Harvard nutritionists say folic-acid supplements can mitigate the dangers of drinking (Curr Oncol Rep, 2007; 9: 31-41).
So what's the bottom line? Death rates. There's no doubt that heavyand, particularly, binge drinking will shorten your life. Nevertheless, study after study has shown that you'll live longer with moderate regular alcohol consumption. The latest evidence suggests that the magic number is two to four drinks a day for men, and one to two drinks per day for women (Arch Intern Med, 2006; 166: 2437-45).
One 'drink' = 1 unit of alcohol = 8-10 g =
a small glass of wine or a half-pint of beer
- Light drinking: under 8 g/day
- Moderate drinking: 8-48 g/day*
- Heavy drinking: over 48 g/day
- Binge drinking: more than 3 drinks in 2 hours
* Authorities differ wildly over these figures