The story of alcohol and health appears to be of the kind of polarizing saga that only the 21st Century could serve up. Yet, as is the case for many hot topics, digging into the data and research—rather than simply affirming our own notions—starts to make answers clearer, even if we don’t like those answers.
Is drinking in moderation healthy? How much is too much? And what are the effects on our health?
Short answer: After we did just that—dig into that actual data and research for this article—both of us ultimately chose to reduce our moderate alcohol consumption. The long answer: Let’s examine why, looking at the trade-offs and biases at play.
First, let’s look at the lens through which most laypeople view alcohol and the biases that result:
- Most folks enjoy some level of alcohol consumption. This can create a confirmation bias cycle, where a person could consciously (or subconsciously) choose to consume information that promotes the potential positives of drinking and downplays the potential negatives.
- Many people have also experienced the negative consequences of heavy alcohol consumption in some form, most commonly hangovers and poor choices while drunk. This could lead to consumption of bias-affirming literature on the health trade-offs of too much alcohol and the issues surrounding acute overconsumption.
Second, let’s look at the lens through which more involved people—ie. non-laypeople—view, promote, or vilify alcohol consumption:
- Doctors: Doctors can be notorious for over-cautioning on various subjects—as they likely should be, given that their oath places a reasonable (though not absolute) emphasis on minimizing harm, and liability makes them likely to exercise even more prudence. This can lead to recommendations that are either extreme in the direction of a safest possible approach, or are simply in keeping with mainstream advice from other MDs. These both may be the correct approach, but it’s wise to keep these things in mind when considering their potential biases.
- Researchers: Scientists usually enter a research field because of personal interest in the topic or a suspicion that the area needs more clarity or is not fully understood by the public. While most scientific researchers are unlikely to have intense personal interest in either increase or decreasing alcohol consumption, it is certainly reasonable to expect that some of them may have had experiences that lead them to this field and to feel like alcohol may be harmful. Thus, we must consider whether the balance of studies are likely to focus on showing that lower alcohol consumption is more optimal for health.
- Alcohol industry: The alcohol industry clearly benefits from alcohol consumption receiving a scientific and medical stamp of approval. This can affect public policy, as well as publication and circulation of guidelines or research that promotes the health benefits of alcohol consumption and downplays the negatives.
The Consensus on Health Consequences of Extreme Drinking
When it comes to alcohol consumption and health, most of the commonly agreed upon facts are things you have probably already heard: Heavy drinking causes cancer, liver disease, and heart disease, as well as a number of other long-term serious health issues.
These things are repeated ad nauseum, in part because it is an intentional strategy by the alcohol industry to draw attention to the negatives of alcohol abuse, rather than to focus on the more nuanced but still negatives effects of lighter alcohol consumption.
But, if you’re like most athletes, you look at the standards for heavy or moderate drinking and think to yourself: “Well, two glasses of wine every day is kind of a lot and I never have 20+ drinks per week. I don’t know if I’m too concerned about the effects of more than 14 alcoholic drinks per week, because I haven’t drank that much since my early 20s!”
So, what about those of us who aren’t heavy drinkers, but who still have a few drinks per week or a glass of wine at night with dinner? What about those of us who are training enough that our desired alcohol consumption is maybe four to six drinks on our heaviest drinking social weeks?
By almost all research accounts this is considered “light” drinking. Depending on the source, light drinking usually falls somewhere around seven beverages per week.
Do we, athletic and healthy moderate or light drinkers, have anything to worry about?
The alcohol industry would say, “Absolutely not! Enjoy! You might even get that much-touted heart benefit from red wine!”
Yet, the research appears to tell a more nuanced story. And in some cases, alarmingly so.
(Disclaimer: If you’re consuming more than six alcoholic beverages per week, please read the rest of this article.)
Yes, Even Light Alcohol Consumption Has Health Risks
We’ll avoid much discussion of the athletic trade-offs of alcohol consumption, because it appears that those negative trade-offs tend to happen much more strongly at levels of alcohol consumption that are already causing chronic negative health outcomes. Basically, by the time it’s affecting your athletic performance it’s probably already affecting your health, according to the research.
Is some of that because of researcher bias? Yes, probably. Take this statement for instance:
“…there will be orchestrated attempts to discredit the science and the researchers, and to confuse the public. The stakes are high for alcohol industries when there is no argument, on current evidence, for a safe level of drinking with respect to cancer.”
With statements like this, there is little doubt that there is some inherent anti-alcohol bias among some research groups.
There almost certainly is a safe level of alcohol consumption. Or, at least, there is a level that if we knew it might increase our risk of future disease by some infinitely small amount, we might still choose to imbibe anyway because our personal trade-offs (ie. relaxation, social time, etc) are in favor.
But there is no debate that the alcohol industry is also actively engaged in misleading, downplaying, and sometimes outright denying relative scientific consensus on the measurable negative health outcomes caused by alcohol. The industry selectively omits the mention of increased cancer risk. More specifically, the alcohol industry appears to avoid any discussion of the link between breast cancer and alcohol consumption. They also highlight, often out of context, the few-and-far-between studies that have found cancer-preventive or other health benefits of alcohol, which, even at the lightest of drinking frequencies, appear to be far outweighed by the costs.
More clearly: Alcohol is not good for you, on net. It’s probably not even close, even in the lightest of drinking.
That’s why righteous and health-minded researchers often claim no safe limit. Zero drinking is their recommendation. But obviously, that’s not an absolute truth or else one drink consumed annually would have a measurable effect. (It does not.)
More importantly, the zero drinking line never gains any traction in public policy or the media.
If you are like us, you want a number. You want to be able to consider where the line is that truly makes a difference. There must be a clear number of drinks per year, per month, per week, or per day that we can put our finger on and say, “This is what we’re OK with.”
But what is it? How small is that number?
What Number of Drinks is Safe?
How much alcohol can we actually have before we ought to feel like any increased risk of cancer or other disease is no longer immeasurably small, but at least slightly meaningful? At what amount of alcohol consumption are we doing virtually no harm to our future self, and do the potential social and emotional benefits outweighs the negatives?
The answer: Probably less than you’re currently consuming. Maybe a lot less.
(If your great great grandparents read the following, it might have to come with a trigger warning for stirring up emotions from the Prohibition era.)
After extensive research, the current summary of the best and most comprehensive scientific literature is:
- There is increased breast cancer risk from consuming four to six typical alcoholic beverages per week.
- About 5% of all breast cancer cases are attributable to alcohol consumption.
- More than 10% of all colorectal cancer cases are attributable to alcohol consumption. A non-negligible portion appears in the seven drinks per week range.
- Breast, colorectal, stomach, liver, mouth, and throat cancer risk are all measurably increased with drinking levels that most people would not consider problematic. Dramatically increased risk appears to occur somewhere between one to two beverages per day.
- There are absolutely years of life lost, on average, with greater than 14 drinks per week, and the number of years of life lost accelerates dramatically from there.
- Of course, many people who drink nothing at all will get cancer. And many people drink more than 14 beverages per week will live long lives.
- Increased cancer and mortality risk starts to become measurable and meaningful for women around half an alcoholic beverage per day.
- Increased cancer and mortality risks starts to become measurable and meaningful for men around one alcoholic beverage per day.
- The difference in increased risk between men and women appears to come primarily from the causal link between even light alcohol consumption and breast cancer in women, and secondarily from population differences in body size and weight.
Our advice on alcohol consumption:
If you want to rest assured that you are not measurably increasing cancer risk and potentially taking years off your life, limiting yourself to about one alcoholic drink per week is probably a safe bet. One glass every two weeks is probably better. Men, limit yourself to two adult beverages per week, and one would probably be better. We think that red wine may be a better bet, but that the health benefits are almost certainly outweighed by the negatives. Let your decision be guided by a rational weighing of tradeoffs, including social and emotional consideration, rather than some possible small cardio-protective effect.
Most of all, understand that for both men and women there appears to be a linear dose-response relationship between early mortality and alcohol consumption. You get to weigh the trade-offs in your own life.
Dr. Alex Harrison, a certified USA Triathlon coach, holds a PhD in Sport Physiology and Performance. He is the author of The RP Diet for Endurance, creator of the RP Endurance Macro Calculator, and has authored and contributed to dozens of articles. When he isn’t pumping out training and nutrition plans in his RV-garage-turned-mobile-office, he can be found on his bike, clinging for dear life to his wife’s wheel.
Michelle Howe is a registered dietitian, holding a Masters in Sport and Exercise Science, Cat 1 cyclist, All-American triathlete, and co-author of The RP Diet for Endurance. When she’s not dropping her husband on every ride, she can be found running with her dog, Dash, in the trails near her full-time RV home.