Alcohol. Friend or Foe?

Why the research on alcohol has changed my thinking.

Every other week there is an article that makes claims about the benefits of alcohol and then another about its potential harms.

So what’s the deal?

Is alcohol good or bad for you?

Vermeer van Utrecht Man drinking wine. 1656.

Let’s start with some simple facts.

Alcohol is a toxin.

Alcohol is a factor in¹:

• 30% of suicides

• 40% of fatal burn injuries

• 50% of fatal drownings

• 50% of homicides

• 65% of fatal falls

• 29% of fatal road traffic accidents

Globally, alcohol is responsible for 3 million deaths per year; in the United States, it is the third leading cause of preventable death² ³.

It is hard to see the upside when you see these figures.

So let’s go a little deeper.

First off, I drink alcohol. Not a lot. But I do drink.

So any comments made here are not some puritanical position on alcohol but reflections on the data that exist in the literature.

Multiple studies have demonstrated that excess alcohol consumption, usually defined as consuming greater than 2 to 4 drinks per day, is associated with worse outcomes and a greater likelihood of dying when compared to someone who drinks less than 2 to 4 drinks per day⁴.

Alcohol Dosing and Total Mortality in Men and Women: An Updated Meta-analysis of 34 Prospective Studies. Arch Intern Med.2006

In the study shown above, females start to accrue an increased risk at greater than two drinks per day on average and males at greater than four drinks per day.

These findings shouldn’t come as a surprise to anyone.

Surprisingly, on average, individuals who consume less than two drinks per day appear to have better outcomes than those who do not drink at all. This is where things start to get a little counterintuitive, and the story of alcohol being beneficial for you starts to appear.

This relationship is known as a ‘U’ shaped curve where those in the middle have the best outcomes, and those on the edges have worse outcomes. A kind of ‘Goldilocks’ relationship; “Not too hot. Not too cold. Just right.”

How might we explain this?

Enter the darling of the 1990s, Resveratrol. This compound in red wine spawned the mantra that red wine was ‘good for your heart’. This was based on research that suggested that it might reduce cholesterol levels, among other things.

But to consume the levels of Resveratrol tested in some of the animal studies that demonstrated benefit, you would have to drink 40 litres of wine…… Per day.

Not exactly a feasible strategy. Even with the best will in the world.

Let’s look at a more plausible explanation.

Data on alcohol consumption and outcomes are almost always based on observational data, not randomised controlled trials. This means that other factors or ‘confounders’ may explain the difference between the groups, not the alcohol consumption alone.

When you look at the trials that suggest a benefit of modest alcohol consumption, you will often find that this group tend to exercise more, smoke less, be in a higher socioeconomic bracket etc. This is referred to as a ‘healthy user bias’ and is likely to explain the difference between the groups.

Most trials try to correct or adjust for these confounders, but in truth, it is very hard to do. A recent publication looked at this problem and attempted to (as much as possible) correct for these ‘healthy user’ bias factors and then compare outcomes between alcohol consumption groups. The results were a little more in line with what we might expect.

Those in the lowest alcohol consumption category had the best lifestyle factors overall. When these healthy factors were corrected for, any benefit seen with modest alcohol consumption disappeared. What remained was a linear relationship between alcohol consumption and coronary artery disease⁵. Much more what you might expect.

Association of Habitual Alcohol Intake With Risk of Cardiovascular Disease. JAMA Netw Open. 2022

Research like this and other studies is where the more recent media reports of ‘any’ alcohol being bad for you have come.

So, alcohol is a toxin. But, as Paracelsus notes:

“The dose makes the poison.”

Even water consumed to excess can be lethal.

We know that excess alcohol consumption is harmful. But I don’t think there was any great uncertainty around that point.

The key takeaway is that modest alcohol consumption is unlikely to be ‘beneficial’ to you. As much as you loved the idea that red wine was good for your heart, we can say with reasonable confidence that this is not the case.

The real question we need to answer is whether consuming modest amounts of alcohol is considerably worse for you when it comes to heart disease and death from any cause.

Based on the literature to date, it seems that the incremental risk for modest amounts of weekly alcohol consumption is likely to be small. But that doesn’t mean there are no downsides.

Sleep

One of the main reasons I significantly reduced my alcohol consumption was its effect on my sleep. If I drink more than one drink, I find that the quality of my sleep gets worse. I am much more likely to wake in the middle of the night and feel the effects the following day. But that’s just my personal experience.

Although alcohol is likely to make you fall asleep faster, it impacts your sleep quality⁶. Additionally, alcohol also reduces the percentage of REM sleep a person gets overnight⁷.

A workaround for me is to consume any alcohol during the daytime, so my sleep is unlikely to be affected, and if I am going to have a drink, I make sure it is worthwhile. I.e. I am with friends, or it is a high-quality drink. No more drinks on airplanes for me. Mainly because you lose about 30% of your sense of smell and taste in a pressurised cabin and therefore you are less likely to enjoy your drink⁸. Why do you think they serve you tomato juice and the fact that you think it's tolerable?!

Humans have been consuming alcohol as far back as the ancient Egyptians, and some evidence suggests the Chinese were consuming alcohol as far back as 7000 B.C. So I don’t see alcohol disappearing any time soon.

The question we all need to ask is:

How much are we realistically drinking on a daily or weekly basis &

Is it likely to be doing us harm?

Only you can answer that question.

The only way to be certain you are doing no harm is to eliminate alcohol entirely. But life is full of risks, some of which we can control, some we cannot.

And some risks are worth taking.

Want to eliminate all road traffic accidents worldwide?

Simple.

Ban cars.

But at what cost?

The risks of driving are a risk most of us are willing to take.

Alcohol has risks.

We must all aim to minimise those risks.

Whatever that means for you, only you can decide.

1. https://www.rethinkingdrinking.niaaa.nih.gov/How-much-is-too-much/Whats-the-harm/What-Are-The-Consequences.aspx

2. Mokdad, A.H.; Marks, J.S.; Stroup, D.F.; and Gerberding, J.L. Actual causes of death in the United States, 2000. JAMA 291(10):1238–1245, 2004. Erratum in JAMA 293(3):298, 2005.

3. Centers for Disease Control and Prevention (CDC). Alcohol and Public Health: Alcohol-Related Disease Impact (ARDI). Annual Average for United States 2011–2015 Alcohol-Attributable Deaths Due to Excessive Alcohol Use, All Ages.

4. Alcohol Dosing and Total Mortality in Men and Women: An Updated Meta-analysis of 34 Prospective Studies. Arch Intern Med.2006;166(22):2437–2445. doi:10.1001/archinte.166.22.2437

5. Biddinger KJ, Emdin CA, Haas ME, et al. Association of Habitual Alcohol Intake With Risk of Cardiovascular Disease. JAMA Netw Open. 2022;5(3):e223849. doi:10.1001/jamanetworkopen.2022.3849

6. Britton, A., Fat, L.N. & Neligan, A. The association between alcohol consumption and sleep disorders among older people in the general population. Sci Rep 10, 5275 (2020). https://doi.org/10.1038/s41598-020-62227-0

7. Ebrahim IO, Shapiro CM, Williams AJ, Fenwick PB. Alcohol and sleep I: effects on normal sleep. Alcohol Clin Exp Res. 2013 Apr;37(4):539-49. doi: 10.1111/acer.12006.

8. Burdack-Freitag, Andrea & Bullinger, Dino & Mayer, Florian & Breuer, Klaus. (2010). Odor and taste perception at normal and low atmospheric pressure in a simulated aircraft cabin. Journal für Verbraucherschutz und Lebensmittelsicherheit. 6. 95-109. 10.1007/s00003-010-0630-y.