How much should you drink (640 x 480)

All of us wine sippers and beer guzzlers embraced with enthusiasm the findings of many previous studies that had linked moderate drinking with reduced risk of death from cardiovascular disease, while heavier drinking has been linked with increased mortality. Personally, I unburdened myself of any guilt feelings: I am doing it for my health, sort of like taking medicine… A couple of glasses of wine with dinner are not going to kill me, they are actually “good for you”.

But wait a minute. Such studies have typically measured individuals’ average alcohol intake. A drawback of that approach is that averaging obscures potential differences between people who sometimes drink heavily and those who consistently drink small amounts of alcohol. Sort of like drowning in a lake with an average depth of one foot. Average intake makes no distinction between the individual who has seven drinks, all on one day each week, for example, and someone who has just one drink, every day.

 

The importance of being consistently moderate

Rosalind A. Breslow, Ph.D, MPH, an epidemiologist in the National Institute of Alcohol Abuse and alcoholism’s Division of Epidemiology and Prevention Research, and Barry I. Graubard, Ph.D, a statistician in the Division of Cancer Epidemiology and Genetics at the National Cancer Institute, examined data from a nationwide health survey conducted in 1988. Almost half of the nearly 44,000 people who participated in the survey identified themselves as current drinkers who had at least 12 drinks of alcohol during the previous year. By the end of 2002, more than 2,500 of these individuals had died. Drs. Breslow and Graubard compared their causes of death with the alcohol consumption patterns they reported in the survey. A report of their findings appears in the March 2008 issue of National Institute on Alcohol Abuse Alcoholism.

 

What they found:

In men, the greater the amount of alcohol that they consumed on drinking days, the greater was their risk of death from cardiovascular disease. For example, men who had five or more drinks on drinking days had a 30% greater risk for cardiovascular mortality than men who had just one drink per drinking day. Alcohol quantity was also associated with increased mortality from cancer among men.

The frequency of drinking was associated with decreased risk of death from cardiovascular disease among men; those who reported drinking 120 to 365 days per year had about 20 percent lower cardiovascular mortality than men who drank just one to 36 days per year. The current study was not designed to determine why drinking frequency might have a protective effect.

Among women, frequent drinking was associated with a significantly increased risk of cancer, while increased quantity was associated with risk for mortality from all causes.

 

Several questions

    • The U.S. Dietary Guidelines for Americans advise men to have no more than two drinks per day and women to have no more than one drink per day.
    • Why are women condemned to only half the pleasure? If there is sexism here, at least it is grounded in science. Because women’s bodies generally have less water than men’s bodies, a given amount of alcohol is less diluted in a woman’s body than in a man’s. Consequently, when a woman drinks, the alcohol in her bloodstream typically reaches a higher level than a man’s even if both are drinking the same amount.
  • What can we make of the finding that men who drink moderately, no more than 2 glasses a day, but frequently (120-365 days a year), are more protected than men who drink only 1-36 days a year?

The short answer: I don’t know. But I would hazard a guess that the men who drink more frequently are much happier (hence, healthier) than the occasional drinkers. I’ll drink to that!

What about the iniquity of women who drink frequently having a higher cancer mortality, and the ones who drink a lot having a higher mortality from all causes?

As JFK once famously observed, life is not fair. I am sure there is a biological explanation for this unfairness, but it’s not going to make a difference. Ladies, you will have to take it easy with the alcohol. Sorry.

As to the rest of us: Cheers!

Dov Michaeli, MD, PhD
Dov Michaeli, MD, PhD loves to write about the brain and human behavior as well as translate complicated basic science concepts into entertainment for the rest of us. He was a professor at the University of California San Francisco before leaving to enter the world of biotech. He served as the Chief Medical Officer of biotech companies, including Aphton Corporation. He also founded and served as the CEO of Madah Medica, an early stage biotech company developing products to improve post-surgical pain control. He is now retired and enjoys working out, following the stock market, travelling the world, and, of course, writing for TDWI.