The Alcohol-Blood Sugar Connection: Effects, Risks, and Possible Benefits

How can I drink but not have it impact my metabolism?

(Read to the end to find out!)

Every week a client asks me about the impact of alcohol on their blood sugar. It’s a great question and the answer isn’t simple or obvious.

In fact, for many, it seems that alcohol IMPROVES their blood sugar… at least in the short term. During my Hack Your Blood Sugar Using a CGM programs, I’ve had more than one client A/B test alcohol with dinner and notice improvements in their overnight blood sugar on their continuous glucose monitor. I’ve also seen alcohol cause hypoglycemia overnight on their glucose reports. These conflicting observations made me decide to dive a little deeper. I was actually having trouble telling some people NOT to drink alcohol at night because they found it consistently lowered their overnight blood sugar (in the short-term, at least) to a healthier level.

How Alcohol Affects Blood Sugar Levels

It’s complicated right from the get-go. Let’s dive in and figure this out.

First of all, all of this is happening in the LIVER. Many people don’t realize that when it comes to metabolism and glucose regulation, the liver is king. The liver has a lot going on at any one time. So let’s zoom in on just 3 of its jobs on a busy evening of eating and drinking.

1. Everything you eat makes a pass through the liver before anything else. The liver is like the triage nurse in the ER. It deals with metabolism.

2. The liver is where we will detoxify that alcohol (it’s a toxin, let’s not forget).

3. The liver is responsible for maintaining steady glucose levels overnight and any time we are fasting.

The liver is a powerhouse, but it can only do so much at once. So if you eat a really big meal, with dessert later, and a bowl of popcorn even later, that’s keeping it busy. Throw back 2-3 glasses of wine or beer, and it could start to overload the system. A healthy liver will be able to deal with it all eventually, but it might take a while.

Now let’s focus on the liver’s role in regulating glucose levels. At night when you are fasting, you need to keep your glucose levels in the Goldilocks Zone around 80-100mg/dl. Since you’re not eating, your liver will employ a few strategies to produce extra glucose and send it into your blood to fuel things as you sleep. It can either break down stored glycogen (glycogenolysis) or make new glucose from other sources (gluconeogenesis).

Alcohol inhibits two things in the liver that will lower blood sugar: Gluconeogenesis and glycogenolysis

• Glycogenolysis (breaking down glycogen) is when the liver takes its stored glycogen (storage glucose in the liver and muscle) and releases glucose into the bloodstream to keep blood sugar levels even while you are fasting (or exercising or sleeping).

• Gluconeogenesis (making new glucose) is how the body MAKES glucose from substrates like glycerol, lactate, pyruvate and protein.(1)

So you could see how this might sound like a GOOD thing if you normally experience elevated blood sugar overnight. I mean, some people take metformin and berberine and they do something similar. As I mentioned at the beginning, I’ve had a number of clients using a continuous glucose monitor and alcohol seems to give them BETTER blood sugar readings overnight.

Combine this with the mountains of epidemiological data (2) saying that moderate alcohol consumption is associated with a reduced risk of cardiovascular disease… Well, a glass of wine with dinner sure seems like a more enjoyable strategy than taking metformin or berberine.

But there is more to the picture.

Can Alcohol Consumption Lead to Hypoglycemia?

The short answer to this is a definitive, “YES!” But not always.

When I’m looking at continuous glucose monitor data and I see blood sugar looking erratic overnight and dipping low around 2-3AM, the first thing I ask is, “Did you drink alcohol the night before?”

It will depend a lot on the individual, what they ate, how late they ate it, and how much alcohol they drank.

Together, glycogenolysis and glucogenesis are how the liver maintains healthy glucose levels overnight while you are sleeping and fasting so you don’t get hypoglycemia (low blood sugar).

After going to bed, your liver will STILL be dealing with your meal (especially a big, late meal). You’ll also have all that alcohol floating around. Once you have metabolized all the glucose from your meal, it’s time for your liver to start regulating your blood sugar while you sleep.

But it can’t do that effectively, because the alcohol is inhibiting glycogenolysis and gluconeogenesis. Sometimes, it causes your blood sugar to go TOO low.

I think many people know that when they drink in the evenings, they are prone to waking up around 2 am. This is often because blood sugar drops too low and the body produces a little adrenaline to bump it back up. This is one of the ways your body deals with low blood sugar. During the daytime, it can make you feel anxious or angry. At night, the adrenaline wakes you up.

If you are using a continuous glucose monitor (CGM), it can be hard to tell the difference between a real hypoglycemic episode and a pressure low. The CGM will give a false low reading if you are lying on the arm with the sensor. That’s why a little more investigation is helpful. Also, a real hypoglycemic reading will often have a rebound elevation in blood glucose beyond the baseline level.

Interactions Between Alcohol and Diabetes Medications

When people are already taking a glucose-lowering agent like metformin or even berberine, drinking alcohol at night can cause more extreme low blood sugar.

The Medline warning for metformin even reads: “Tell your doctor if you regularly drink alcohol or sometimes drink large amounts of alcohol in a short time (binge drinking). Drinking alcohol increases your risk of developing lactic acidosis or may cause a decrease in blood sugar.”(3)

This is because excess alcohol consumption reduces the clearance of lactate and this increases the risk of metformin-associated lactic acidosis (MALA). (4)

I’ve seen similar exaggerations in blood sugar reduction overnight when a client uses berberine and drinks more than one drink in an evening.

The Relationship Between Alcohol and Insulin Resistance

Now let’s look at a more long-term impact of alcohol.

Insulin resistance is when the cells (like muscle cells) are not letting the glucose in. Your pancreas is still producing plenty of insulin, which acts like a key to let glucose into muscle and fat cells to lower your glucose after a meal. But when your cells are insulin resistant, the glucose doesn’t go in. This leads to higher glucose AND insulin levels.

The literature supports the conclusion that alcohol causes an increase in insulin resistance. This means that when drinking, your ability to store glucose in your fat/muscle cells is reduced, leading to prolonged high glucose levels. (5,6)

So you can still produce insulin, but when that insulin is knocking on the door of your muscle cells to store some of the excess glucose away from your pasta, the muscle cell is saying, “No thanks.” The result is typically higher insulin production to get the same amount of glucose stored away.

In a previous article I explained that insulin resistance is the cause of metabolic syndrome and leads to elevated blood pressure, triglycerices, visceral adipose tissue and inflammation. It also puts a person on the path to type 2 diabetes. So anything that increases insulin resistance will lead to reduced metabolic health in the long run.

The link between alcohol and uric acid

Uric acid has been getting more air time lately for good reason. It drives a metabolic switch that leads to fat storage, fatty liver, and if it gets bad enough, gout.

Even if you never get gout, you should be thinking about uric acid. That’s because when uric acid is elevated, it kicks off a metabolic switch that leads to:

• Increased “foraging” (think of walking into the kitchen and searching for a snack)

• Improved absorption of sugar

• Fat storage

• Increased blood pressure

This is a metabolic pathway called the polyol pathway. It’s a vicious cycle kicked off by high fructose consumption, dehydration, high salt intake, high glucose levels, or alcohol consumption. This polyol pathway is a slick survival mechanism our bodies have developed to help us store lots of fat when the fruit is ripe to help us survive the lean winters. There are a few different things that will trigger this polyol pathway (or metabolic switch) that causes your body to produce fructose and then uric acid. (7,8) They include:

1. Concentrated blood solute level (this could be high blood sugar level, high salt intake or dehydration)

2. Alcohol consumption

3. High fructose consumption

So drinking alcohol can cause an increase in uric acid production, which flips this metabolic switch. In his book, Nature Wants Us To Be Fat*, researcher Dr. Richard Johnson gives us some strategies to mitigate this, which I’ll share at the end.

*Note: This book is very readable and interesting if you want to learn more about it.

What’s the real story with “moderate” alcohol consumption?

As I was working on this article, Peter Attia, MD, published a thoughtful review of the relationship between alcohol consumption and the risk of cardiovascular disease (CVD). Historically, there has always been an ASSOCIATION between low/moderate alcohol use and low CVD risk. I’m grateful for Dr. Attia’s efforts to tease out what this might mean and if moderate alcohol consumption is indeed beneficial.

First, let’s look at what moderate actually looks like.

• Never drinking: 🥤no alcohol

• Low alcohol: 🍷<10g/day (10g = 100ml or 3.3 oz wine)

• Moderate alcohol use:🍷🍷 10-30g/day (20g = 200ml or 6.6 oz wine)

• High alcohol use:🍷🍷🍷 >30g/day (40g = 400ml or 13 oz wine)

Low and moderate drinkers were associated with a lower risk of CVD, which included lower waist circumference, blood pressure, fasting triglycerides and LDL. (2)

However, a 2022 study looking at habitual alcohol consumption of nearly 400,000 people suggested that ANY amount of alcohol increased blood pressure and the risk of CVD. (9)

This makes sense when you think about the link between alcohol, uric acid, and blood pressure. When you drink alcohol, uric acid will rise and so will blood pressure. And elevated blood pressure will always lead to increased CVD risk.

Alcohol reduces GLP-1 and increases appetite

Unless you’ve been living under a rock, you’ve likely heard about the miracle weight loss drugs called Ozempic, Wegovy and Monjaro. They are all similar (if not the same) and act by stimulating the GLP-1 receptor in the intestines to reduce appetite and improve insulin production. GLP-1 has receptors in the gastrointestinal tract as well as in the pancreas, nervous system and other areas in the body.

These drugs have been really helpful to many with type 2 diabetes and obesity, especially when overeating and binge eating are in the picture.

There’s also an interesting link between GLP-1 and alcohol!

Alcohol consumption lowers GLP-1. So it seems that alcohol is like an anti-weight loss drug, but is that any surprise? Let’s put this together with what we learned above about uric acid and that metabolic switch. It seems there are two different ways that alcohol is going to encourage you to eat more. It stimulates your appetite and increases the foraging response. Neither of these will help you with your blood sugar.

Specific Types of Alcohol and Their Impact on Blood Sugar

All this might have you wondering if you should ever drink alcohol again. While alcohol is a toxin, the occasional drink will not severely impact the average healthy person. So, let’s talk about better ways to go about it.

First, certain drinks are worse for blood sugar.

• Beer is probably the hardest. It will raise uric acid levels the most rapidly due to its high content of purines, yeast/umami, and alcohol.

• Cocktails that use sweetened beverages are next. We know that drinking your calories is the worst way to consume them, and they alone will trigger that metabolic switch producing uric acid. Combine that with alcohol and you have a double whammy.

• Sweet wines like port and sherry are next.

So, the least impactful alcoholic beverages would be moderate use of wine and spirits that are mixed with unsweetened mixers. So think vodka and soda rather than rum and coke.

Strategies to Minimize the Impact of Alcohol on Blood Sugar

In his book Nature Wants Us to Be Fat, Richard Johnson gives further tips on how to mitigate the impact of alcohol.

1. Drink it slowly: Sip, don’t chug

2. Alternate it with water: staying hydrated reduces the impact on your metabolism

I would add to this to stop drinking early enough to metabolize the alcohol before bedtime. I encourage my patients to sip a small glass of wine with dinner, but not after, or enjoy an aperitif at happy hour.

And then there is good old moderation. If you love a good margarita, then just have one and don’t drink them so often. Also, don’t combine it with a bunch of chips or carb-heavy meal.

Enter Bitters!

Aromatic bitters are an old-fashioned ingredient in aperitif (sometimes called digestif). Originally from Italy, an aperitif is an alcoholic drink consumed prior to meals to stimulate appetite. They have long been used to improve digestion and there is good data to support that. You can also use bitter foods like a little dandelion leaf in a salad, radicchio, or other bitter greens as a first course.

In fact, the use of digestive bitters (or bitter food) can stimulate GLP-1 (much like Ozempic).

We have receptors for these bitter flavors in our mouth and intestine. They trigger the secretion of various gut hormones including GLP-1, CCK, ghrelin and PYY.

In addition to improving bile release and general digestion, they also impact appetite and improve glucose and lipid levels.

Common bitter foods include dandelion greens and roots, radicchio, kale, Jerusalem artichokes, coffee, arugula, dill, turmeric, gentian, ginger, citrus, and Brussels sprouts. (10,11)

So it would make sense that not only would they help contol appetite, but based on recent research done on Ozempic-type drugs, would curb the urge to over indulge in alcohol as well.

How to use bitters

There are many good brands of digestive bitters, but if you like a cocktail before dinner, consider reformulating to include bitters, a club soda and citrus. Heck, you can even make it alcohol-free. For convenience, I often use a spray bottle of bitters from Urban Moonshine which I keep in my handbag.

Take-home tips

My hope with this article is not to convince you to never consume alcohol again. However, I do want to light a fire under you if your regular alcohol consumption exceeds a few drinks per week.

For example, a dear friend of mine is a doctor in her mid-50s who competes in ultra-endurance sports. Her usual diet is predominantly fish, game meat and vegetables and she cooks most of her own food. When she goes out to socialize, she puts away a pint or 2. This has minimal impact on her overall health because she’s physically active and the rest of her diet keeps her blood sugar well-controlled. The problem is when we combine a sedentary lifestyle, poor daily glucose control, a nutritionally poor diet AND daily alcohol use. It’s what you do 80-90% of the that matters the most.

If you find that your “moderate use” is half a bottle of wine most nights, this is having a negative impact on metabolic health. You’re fooling yourself if you think this is indeed moderate or improving your cardiovascular health just because you’re drinking red wine. Light use can creep up to moderate and heavy use before you know it. It will impair sleep, raise blood pressure, and degrade your health quickly. I encourage you to look at the definitions of low, moderate and heavy alcohol consumption above and evaluate what you’re really drinking.

There are ways to enjoy alcohol that minimize the health impact that including reducing quantity, stopping earlier, changing your drink, and/or focusing on hydration. Like other diet and lifestyle strategies, the key is moderation.

Test it out yourself!

Continuous glucose monitors (CGM) are my go-to methods to assess blood sugar and metabolic health. We use them for 2 weeks to get a good picture of what’s going on under the hood and what factors are impacting blood sugar levels the most. Then an additional 2-6 weeks are all that’s needed to help dial in the necessary diet and lifestyle changes to really start moving the needle.

After using this CGM tool extensively, I see it as both a time-saver and a money-saver. We get great data quickly and are able to zero in on just the strategies that will help the most. This eliminates the need for unnecessary changes or clumsy use of medicine or supplements. We can test each thing, judge its merit, keep it, or toss it out. This results in money saved, less work, and rapid improvement in blood sugar levels. I’ve seen diabetic levels of blood sugar normalize in 1-3 months. Once people know what to do, they don’t have to be slaves to the cookie-cutter approach to diabetes. They can personalize their strategy. It’s easier, works quickly and it gives them so much more control over their lives. Listen to Mike’s story of how he turned his blood sugar around quickly.

When my clients use it, I tend to set them up 1:1 or have them join one of our 4-week group programs that run every other month. It’s actually fun! Most people find they enjoy the process and leave feeling more in control of their health. If you want to learn more about our program, click HERE.

References

1. Steiner JL, et al. Impact of alcohol on glycemic control and insulin action. 2015. Biomolecules. Sep 29;5(4):2223.

2. Hansel B, et al. Relationship between alcohol intake, health and social status and cardiovascular risk factors in the urban Paris-Ile-De-France cohort: is the cardioprotective action of alcohol a myth? 2010. Eur J of Clin Nutr 64,561.

3. https://medlineplus.gov/druginfo/meds/a696005.html Metformin.

4. Yamagishi H, et al. Metformin-associated lactic acidosis induced by excessive alcohol consumption. 2023. Intern Med. Nov 13. Online ahead of print.

5. Shelmet JJ, et al. Ethanol causes acute inhibition of carbohydrate, fat and protein oxidation and insulin resistance. 1988. J Clin Invest Apr:81(4):1137.

6. Avogaro A, et al. Alcohol impairs insulin sensitivity in normal subjects. 1987. Diabetes Res. May;5(1):23.

7. Johnson RJ, 2022, Nature Wants Us to Be Fat. Dallas, TX BenBella Books Inc.

8. Sutin AR, et al. Impulsivity is associated with uric acid: Evidence from humans and mice. 2014. Biol Psychiatry. Jan 1;75(1):10.1016/j.biopsych.2013.02.024

9. Biddinger KJ, et al. Association of habitual alcohol intake with risk of cardiovascular disease. 2022. JAMA Netw Open. 5(3):e223849.

10. Chou, W. Therapeutic potential of targeting intestinal bitter taste receptors in diabetes associated with dyslipidemia. 2021. Pharmacological Research 170:105693.

11. Rezaie P, et al. Effects of bitter substances on GI Function, energy intake and glycaemia-do preclinical findings translate to outcomes in humans? 2021. Nutrients. Apr;13(4):1317.