Studies Try To Find The Right Doses Of Our Favorite Drugs: Coffee And Alcohol
The world’s most-used stimulant and best-loved depressant – caffeine and alcohol, respectively – have shared an interesting phenomenon in recent years: They’ve both moved from the probably-not-healthy-but-socially-acceptable category to the probably-healthy-in-moderation-because-science-says-so category. Based on the scientific evidence of the last decade or two, coffee is now believed to reduce risk of everything from Parkinson’s and Alzheimer’s diseases to depression to erectile dysfunction to some forms of cancer to overall mortality. Alcohol is thought to reduce the risk of heart disease, stroke, and perhaps even curb obesity and type 2 diabetes risk. Each drug has been shown to have these much-desired health benefits, and few risks, provided they’re consumed in moderation. The operative words are of course in moderation.
But the exact amount of each that is really safe to consume hasn’t been so clear, particularly since it can change as new research comes out. Two new studies make some progress in quantifying the safe levels of consumption for each of the drugs.
A report from the European Food Safety Authority (EFSA) looks back over the scientific evidence, and arrives at a heartening number regarding caffeine dosage for the general population: 400 mg/day, which is about the equivalent of five shots of espresso, or four 8-oz cups of coffee. “Caffeine intakes from all sources up to 400 mg per day…consumed throughout the day,” write the authors, “do not give rise to safety concerns for healthy adults in the general population, except pregnant women.” This group, the authors say, should stick to 200 mg or less per day, as should breastfeeding mothers. Since coffee up to four cups a day (and in some cases more) has been shown in previous studies to have measureable health benefits in the ways mentioned above, it’s nice to have this amount confirmed by the current study as being “safe” for the general population.
Alcohol has been even trickier to make recommendations about, because of its obvious and more serious health risks at higher doses. Most experts recommend no more than one drink per day if you’re a woman, and two if you’re a man. But this seems to change as we age, as a new study in the American Heart Association’s journal Circulation: Cardiovascular Imaging reports: It finds that moderate drinking in people over the age of 71 is associated with greater risk of structural problems in the heart, namely an enlarged left ventricle, which is the heart’s central pump. Women appear to be especially sensitive to this risk.
“In spite of potential benefits of low alcohol intake, our findings highlight the possible hazards to cardiac structure and function by increased amounts of alcohol consumption in the elderly, particularly among women. This reinforces the U.S. recommendations stating that those who drink should do so with moderation,” said study author Alexandra Gonçalves.
Since some experts have recently gone so far as to suggest that doctors tell their middle-aged patients to start drinking for the health benefits if they don’t already, this study clearly throws in a new caveat. What may be acceptable and even desirable in middle-age, may be quite deleterious in old age. (Of course, not everyone agreed with that bold recommendation in the first place. But the new study suggests that even if people do start drinking in adulthood, it may wise to taper off as they age.)
Finally, as many experts are quick to point out, taking up a new habit with an addictive substance may not be so smart, no matter how great the benefits. Studies showing the long-term effects of starting a coffee or alcohol habit for the first time in mid-life, compared to those who continue to abstain, just aren’t there yet. Talk with your doc if you’re debating dabbling in caffeine or alcohol for the first time. These compounds are seductive sirens, for sure, and the studies that support their health benefits may just make them more tempting to begin, and more difficult to stop.