Alcohol and Gut Flora


When people make the change to a healthy diet, they don’t always eliminate alcohol. I mean, sugary and starchy things ferment and alcohol is just a byproduct of that fermentation, right? That’s just nature for ya. Plus, alcohol makes you feel really funny. Ancient man must have drunk it!

Well, maybe sometimes, but without agriculture, alcohol would have been a pretty rare thing. You need quite a bit of starchy or sugary stuff to make it. (Just to give you an idea, it takes 3 pounds of honey to make 1 gallon of mead.) Humans wouldn’t have made it very far if they turned all their food into alcohol. And they wouldn’t have been so successful if they had gone through history drunk.

The lack of presence alcohol has made throughout most of human history has left our bodies ill-adapted to frequent drinks. Hang on, you say. Isn’t moderate drinking supposed to be good for you?

Benefits of Moderate Drinking

We have managed to find plenty of “evidence” to back up our desire to drink.

  • Wine contains resveratol – a potent anti-oxidant
  • Unpasteurized beer contains beneficial organisms
  • Moderate drinking lowers the risk of heart disease, possibly by thinning the blood
  • Alcohol may improve insulin sensitivity – at least it did in a study of mostly women
  • Moderate drinking can reduce the risk of dementia

That’s not all! Alcohol is also known to:

  • Make ugly people look good
  • Enhance story telling
  • Make a boring night fun and boring people interesting
  • Make dishonest people honest and insensitive people sensitive

But all these benefits don’t come without side effects, unfortunately, at least for some…

Alcohol Induced Dysbiosis

The reality is, alcohol does harm. Not only does it increase breast cancer rates, harm the liver, and cloud the judgement, leading to accidents and bad decisions, but it also changes the landscape of the gut.

For many of us coming from a background of digestive problems, we want to avoid anything that can alter the population of bacteria and cause dysbiosis.

Just one drink per day for women — two for men — could lead to small intestinal bacterial overgrowth (SIBO) and subsequently cause gastrointestinal symptoms like bloating, gas, abdominal pain, constipation and diarrhea… Article on the American College of Gastroenterology’s study

SIBO, as it is called, is a pretty big health concern.

The small intestine is not supposed to be a home for much bacteria (the large intestine is). When lots of bacteria do inhabit it, they consume the nutrients which the small intestine would otherwise absorb. This can lead to malnourishment. In addition, the breakdown of these nutrients can lead to gas, bloating, and a change in bowel habits – i.e. constipation or diarrhea.

Consequently, no matter how much healthy food you eat, if you drink, even moderately, you may become malnourished.

Symptoms of SIBO

  • fatigue
  • diarrhea or constipatio
  • depression
  • headaches
  • food cravings
  • rashes
  • excessive gas and/or intestinal noise
  • bloating and abdominal distention

For more info about SIBO check out

Even if you did quit drinking when you went Paleo, you may find that drinking even a little can bring back symptoms. If you didn’t quit drinking after you went Paleo, quitting may be the key that unlocks your door to health.

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  1. As I understand it, it’s that we’ve redefined quantity. There is very good reasons to think that humans were making alcohol as quick at they could, for one really important reason: It purifies the water. If you look at it like that, things make a lot more sense. We’re supposed to be drinking lightly alcohol-ed water, not lightly watered alcohol.

    Even our modern wines are *hard* compared to what we’re traditionally set up to expect. It’s more like the Brits and their barely alcoholic sodas (<0.5%).
    I feel like I just read an article about traditional alcohol levels somewhere, but I can't remember where.

  2. you can find a lot of hunter-gathers who ferment honey or root starches. This is a way of increasing the vitamin and protein content of a marginal diet, as well getting a bit intoxicated. However, these raw toddies are not what the liquor industry is selling us today.
    There’s a good analysis of alcohol benefits and harms here:

  3. It’s all a matter of dose. Our adaptation for alcohol is due mainly to the fact that our own gut flora ferment food and produce alcohol as a byproduct. If we didn’t have the ability to break down small amounts, it would toxify the body pretty quickly.

  4. I like the ritualistic aspects of making and drinking alcohol, but the longer I’ve stayed away the more obvious it is that even small amounts make me feel like crap in a variety of minor ways. It’s just not worth it.

    And when once in a while I feel it is worth it, I have just enough to satisfy the flavour craving and never let myself get intoxicated. It’s shocking to me now to consider that my fiance and I often used to go through a bottle of wine a night, plus a couple of scotches each!

    • I used to drink like that too. Usually at home with my partner or a couple of friends. I quit in 2003, the same time I started making big lifestyle changes. But then I started again in 2007. It brought on similar problems so a little more than a year ago I quit again. Having just one drink every now and then is tempting, but experiencing the symptoms is not!

  5. Yep, I get bloated from drinking too. Also my skin looks somehow duller. Liz, maybe your compliments stem from more radiant skin?

    • Alexandra, my skin does seem brighter, especially around my eyes. But my body language has definitely changed–I caught myself unconsciously smiling at everyone one day–nothing forced at all!

  6. Wow, this is so timely, Peggy! I’ve laid off alcohol completely (red wine) and my bloated stomach is so flat now it is almost concave (in the morning)–this is after only two weeks (and drinking *LOTS* of water). I was debating having one drink tomorrow on Thanksgiving but this helped me to decide not. I love red wine, but I love even more how I feel. Also, maybe a coincidence or not but two anecdotes: (1)I ran into someone at the grocery store today whom I hadn’t seen in about a month and she said “you look so great!”. And she’s never said that before! I was wearing workout clothes, nothing fancy. (2) For some reason over the past week I’ve had several random guys ask me out on dates–I was a similar weight earlier this year, and got nothing like this. I think I am happier, and it is radiating through! Thanks, Peggy.

    • Liz, the flat belly was one of the things I noticed after quitting drinking too! For me, though, I also have to steer clear of fructose. But even when I go fructose free, if I drink, I’ll get bloated, not to mention I feel really crappy…

      • Peggy, yes, inspired by your articles on fructose malabsorption I gave up fruits earlier this year–it wasn’t difficult (except for lemons, which I still crave every day and put in my water). My big downfall are fructans…sometimes I actually want some leeks! I do feel so much better for making this change too. I’m set to have an appointment with my GP in about a month and I am really looking forward to getting food allergy tests…can’t wait to see what comes back.

  7. Thank you thank you thank you thank you. You know when you come across something – something sort of everyday – but instead of it being an everyday thing, it’s life changing??? I think this is one of those times. Not necessarily in re. to alcohol, but your link to siboinfo was like a lightbulb!!!!!!! I knew I didn’t have IBS, but have always suffered (along with my twin) from very obnoxious digestion issues and (in the past, debilitating) fatigue. Is this finally it? Is this the ticket?

  8. This is a great post. I stopped drinking about a year ago but still have wine rarely. It became too social and I knew it didn’t have that much of a benefit for me. The first thing I noticed was my stomach was smaller! Makes sense now.

  9. OK, I’m convinced – you had me at ‘flat stomach’… :-)

  10. The post well represents my opinion on the subject of alcohol on paleo diet too. Many autoimmune disease sufferers turn to paleo diet as an alternative to the mainstream healthcare treatment/nontreatment they receive. As alcohol is a strong gut irritant that compromises intestinal barrier and thus causes leaky gut syndrome it is not recommended and they should quit entirely.

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