When asked how much booze is OK to drink on a diet, most nutritionists sound like Mr. Mackey, the school counselor from South Park: “Alcohol is bad, m’kay. You shouldn’t drink alcohol, m’kay.” As booze carries a host of health risks and offers few real benefits for your waistline, it’s easy to write it off as an unnecessary addition to any diet. But, as with signs that say to shower before entering a public pool, some rules are just asking to be broken, and you’re probably going to drink from time to time anyway—no matter how badly you want to lose weight and get in shape. And who are we to try and stop you?
As booze tends to contain both alcohol and sugar, the question of where it can fit on a ketogenic (or other lower-carb) diet is a big one. After all, “going keto” means cutting carbs way down. But according to Dominic D’Agostino (ketonutrition.org), an assistant professor at the University of South Florida—and one of the world’s leading researchers on ketogenic diets—“If you avoid the kinds of alcohol that have higher carbs and consume other types in low to moderate quantities, you don’t need to totally cut it out.”
We’ll raise a glass to that.
Read on, and you’ll learn exactly how you can make booze a part of your pursuit for a better, fitter body on a low-carb eating plan.
The Expert’s Guide to Alcohol on The Ketogenic Diet
As we described in our guide to going keto, the original, medically-defined ketogenic diet stipulates that you get 75% of your total calories from fat, 20% from protein, and 5% from carbs. (A person following an average 2,000-calorie diet would then limit his/her carbs to around 25 grams per day.) This configuration causes your body to switch its main fuel source from carbs to ketones—molecules that are made from your stored body fat. When this happens, you are considered to be in a state of ketosis. At the same time, when the body needs carbs for energy, it learns to make them itself in a process called gluconeogenesis.
First used in modern medicine by physicians at Johns Hopkins Medical Center in the 1920s, the ketogenic diet was applied to help patients suffering from epilepsy, seizures, and other neurological issues. Since then, research has suggested that keto eating can also help increase mental focus and promote healthy weight loss—perhaps even better than a low-fat diet can. A ketogenic diet also helps your body’s cells become more sensitive to glucose, so your pancreas won’t have to work as hard to carry carbs into them.
The classic ketogenic diet, however, can feel very restrictive and is often hard to follow, especially for athletes and other active people who may need more carbs to fuel exercise and support recovery afterward. In that case, we like what’s called a Mod Keto approach that allows you to consume more carbohydrates than in the traditional ketogenic diet. With Mod Keto, you can get 40–60% of your calories from fat, 20–40% from protein, and 20% from carbs (100 grams for the 2,000-calorie dieter). Though you may not be able to maintain a state of ketosis on this plan, the carbs are low enough to keep you mentally sharp but also generous enough to provide fuel for intense workouts.
What To Know Before Drinking Alcohol on the Keto Diet
There’s no denying it: excessive alcohol consumption can jeopardize several processes in the body, whether you’re keto or not. Your liver recognizes booze as a poison and prioritizes ridding your system of it. While it’s doing that, it stops making ketones and puts the brakes on gluconeogenesis (more on this later). To add to the problem, if you choose sugary beverages, a single serving has the potential to kick you out of ketosis, or eat up most of your carb allowance for the day. Furthermore, an alcoholic beverage can add hundreds of empty calories to your intake. Multiply the effect of one such drink by three or four or more—as in a night of binge drinking—and you’ll easily turn your finely-tuned metabolic engine into a clunky old rust bucket. (For your reference, a study from the National Institute of Health defines binge drinking as consuming five or more alcoholic drinks in a single session.)
Of course, booze is bad for the brain, too. One of the reasons heavy drinking makes you stagger like you just ate a Francis Ngannou uppercut is that alcohol disrupts the cerebellum—the brain region responsible for balance and coordination. In his book Why We Sleep, University of California, Berkeley, professor Matthew Walker explains that even moderate drinking causes memory impairment. He cites a Sleep study that found that participants who consumed alcohol on the same day they performed a learning exercise forgot about 50% of what they’d learned afterward. Even those who had two nights of high-quality sleep between the exercise and their bout of drinking forgot roughly 40% of the information. Walker hypothesizes that alcohol interferes with the process of committing items from short-term to long-term memory, which usually takes place while we’re asleep.
Your Grandma probably swore by the slumber-promoting power of her evening cocktail, and maybe you do, too. But there’s a difference between short-term sedation and restful sleep. While it might make you feel drowsy at first, when the hooch wears off, you can experience a rebound effect that actually stimulates alertness. If you’ve ever woken up at 3 a.m. after a bender, now you know why. Another contributing factor: the hot and cold feelings that alcohol can induce by disrupting the hypothalamus, the area of your brain that modulates body temperature, and other parts of the endocrine system.
In the book, The Sleep Solution, Chris Winter, who has become the de facto “sleep doctor” for NBA, NFL, and other pro teams seeking a rest-related advantage, states that the biggest nighttime issue with drinking alcohol is the disruption it causes to REM sleep. Professor D’Agostino has felt it firsthand. “If I have more than 16 ounces of wine, it not only affects my REM sleep but also the deep restorative stages,” he says, “so I feel lethargic in the morning.”
And then there’s the hangover. Alcohol has a diuretic effect, meaning that it prompts your body to excrete more water. This is why you go to the bathroom twice as often during happy hour, and why you wake up with a dry throat the morning after. Unfortunately, at the same time your body is losing water, it’s losing electrolytes too, throwing off the fluid balance inside you. This can hurt your performance the next time you hit the gym or the trail.
On the bright side, alcohol does have some benefits if you resist the temptation to go overboard with it. Numerous studies have shown that consuming small daily quantities of red wine can help with blood pressure, inflammation markers, and perceived and actual stress levels. In an article published in the Journal of Cardiovascular Disease Research, the phytochemicals in plants known as polyphenols—particularly resveratrol, and quercetin, which are present in wine—were shown to promote heart health. “The positive effects of dry red wine are pretty well established,” says D’Agostino. “Since I started drinking four to 12 ounces each evening, my overall health numbers are the best they’ve ever been. My HDL cholesterol numbers have increased by 25–30% percent.”
More into beer? Then you’ll appreciate the ability of hops to help protect brain cells from oxidative damage, as the Journal of Agricultural and Food Chemistry reported.
How Does Alcohol Affect Your Keto Diet?
When you drink, around 20% of the alcohol (aka ethanol) enters your bloodstream, where it goes on to affect the brain and other parts of the body. The remaining 80% goes to your small intestine and then to your liver. Once in the liver, the process of metabolizing alcohol into energy begins via an enzyme called nicotinamide adenine dinucleotide (NAD). As NAD is also responsible for turning glucose into fuel, the liver temporarily stops glucose metabolism to deal with the alcohol.
“The liver is always going to prioritize metabolizing ethanol,” says Ben Greenfield, author of Beyond Training and host of the Ben Greenfield Fitness podcast. “That will occur over and above gluconeogenesis and utilizing glucose in the bloodstream.” At the same time, as mentioned earlier, fatty acids will stop being converted into ketones. These systems won’t get back on track until the alcohol is burned for fuel.
To add further complications, your body must deal with the waste products that drinking alcohol produces. When your liver breaks down ethanol, it results in acetaldehyde. The body sees this as a toxic threat and slows down fat metabolism further so that it can deal with the load, which it converts to acetyl CoA. At the same time, a buildup of acetaldehyde levels along with the release of NAD prompts the liver to produce new fatty acids. In other words, not only does drinking hurt your ability to burn fat, it encourages you to store more of it—a double whammy.
Now consider that your body can only convert acetaldehyde into 30 ml of acetyl CoA per hour. That’s the best case scenario, with half that amount being the low end of the range. A typical pint of beer (16 ounces) will make most people produce just under 23 ml of acetyl CoA, so drinking just one has the power to prevent your body from burning fat for an hour. If you start imbibing at dinner and continue until last call, you could produce enough acetyl CoA to disrupt fat metabolism for 9 to 12 hours afterward.
Alcohol and Workout Performance and Recovery
If you follow some form of a keto diet and you work out, you’ve got even more reason to cut back on booze. New Zealand’s Massey University has done numerous studies on how alcohol affects performance and recovery. It found that drinking can inhibit the protein synthesis necessary for muscle repair and growth, as well as delay injury healing. In an article on the school’s website, study author Matthew Barnes concluded, “If you’re [in the gym] to perform, you shouldn’t be drinking alcohol.”
There’s also evidence to suggest that alcohol can diminish muscle-building pathways triggered by strength training. A study in the Journal of Strength and Conditioning Research concluded that, “Alcohol should not be ingested after RE [resistance exercise] as this ingestion could potentially hamper the desired muscular adaptations to RE by reducing anabolic signaling, at least in men.”
What Alcohol Can I Drink on a Ketogenic Diet?
Due to all the reasons listed above, alcohol intake should be minimized on any diet, and particularly on keto. But when you do drink, you can limit the damage by giving preference to the lowest-calorie and lowest-sugar beverages available. Below are some examples.
This stuff is your best booze bet. Whiskey, rum, vodka, gin, brandy, and tequila have 0 grams of carbs and 95–105 calories per shot.
Dry white wine
Dry sparkling wines contain 1.3–3 grams carbs and 96–150 calories per five-ounce glass. Other dry whites also fare well, with Brut Cava (2.5 g carbs and 128 calories) and Champagne (2.8 g carbs and 147 calories) rounding out the podium, and Pinot Blanc not far behind (2.85 g carbs and 119 calories).
Dry red wine
Pinot noir, Merlot, Cabernet, and Syrah (Shiraz) have 3.4–3.8 grams of carbs per glass and around 120 calories.
Light (low-carb) and dark beer
While beer is one of the more carb-drenched booze choices out there, the lightest of the lightweight beers aren’t overly dangerous to a keto dieter. Budweiser Select 55™ contains under 2g carbs and 55 calories per 12 oz, and Miller 64™ has 2.4g carbs and 64 calories. Stouts and porters are higher in calories than most other beer options, but they also offer more health-boosting properties, so we don’t think you should exclude them on the weight of the numbers you see on their nutrition labels alone. Guinness Draught™ has 125 calories and 9.4g of carbs (of which only 0.8 grams are sugar), but also boasts high levels of flavonoids, which can help combat inflammation, lower oxidative stress, and reduce the oxygenation of cholesterol.
What Drinks Should I Avoid on a Ketogenic Diet?
The following drinks are known for packing a sugary punch. Indulge in them and you’ll swiftly kiss your ketogenic diet goodbye.
Any alcohol served with a soda, syrup, or fruit mixer
Sodas cram up to 50 grams of carbs in every 12 ounces. Cocktails made with syrups or artificial fruit can pack 20 grams per serving.
Some IPAs contain over 20 grams of carbs and more than 250 calories, and fruity beers can have more than 30 grams carbs and 300-plus calories.
Southern Comfort™ isn’t too bad with just 4.8 grams of carbs and 98 calories per serving. But Jägermeister™ (17g carbs and 154 calories), Kahlua™ (22g carbs, 137 calories), and amaretto (26g carbs, 165 calories) belong in the Hall of Shame.
The amount of tequila’s not the issue. The 100–175 calories and 30 grams of keto diet-busting carbs in the mix are.
These pack a hefty 15–30 grams carbs and have between 200 and 250 calories.
Moscato™, port, and sherry contain up to 18 grams carbs and 75–100 calories per 3 ounces.
How Much Can I Drink On A Keto Diet?
It’s impossible to give a one-size-fits-all answer for how much booze you can drink while still staying keto. We’re all different, and, just as with other kinds of food and drink, alcohol rarely affects two people in exactly the same way. According to D’Agostino, your metabolic state before you start drinking—whether you’re fed, fasted, or semi-fasted—can also affect the degree to which ethanol impacts you.
To be on the safe side, it seems best to limit yourself to two drinks per night at the most. This allowance assumes you’re choosing from the What Alcohol Can I Drink on a Ketogenic Diet list, as these options will make it easier to stay in ketosis, or at least low-carb enough that you’ll avoid disrupting your hormone balance while also gaining the health benefits that alcoholic beverages can provide in moderation.
Remember that moderate drinking is not only tolerable to the body but also helpful. The University of California Irvine’s Institute for Memory Impairments and Neurological Disorders evaluated the lifestyle habits of people who lived to be at least 90. Researchers concluded that those who drank lived longer than those who abstained. Furthermore, drinking up to two alcoholic beverages daily has been found to promote longevity. With that said, Greenfield, warns that going keto can, over time, make you a bit of a lightweight when you drink. “If you’re on a ketogenic diet and your primary source of glucose comes from gluconeogenesis,” says Greenfield, “you might have lower tolerance to alcohol, as your body processes it right away,” he says. When your glycogen stores are depleted, as they are on keto, alcohol gets metabolized much faster and therefore goes to your head much sooner. “And as you metabolize more of the alcohol, you’re going to be dealing with more acetaldehyde,” says Greenfield, “so if you drink too much you could experience a worse hangover.” If you used to guzzle drinks with reckless abandon, your new low-carb lifestyle might cause you to get tipsy on lesser amounts. One drink alone may be plenty for you, so don’t rely on your pre-keto limit as a guide.
If you want to get really scientific about your boozing, D’Agostino suggests buying an Abbot Precision Xtra™ monitor on Amazon.com or at a drugstore to measure your ketone and glucose levels before you start drinking and 30 minutes after you stop. “Then see how different kinds of alcohol and quantities affect you,” he says. “I found that 12 ounces of dry wine is the most I should have, and I often only have six ounces.”
It’s not just a question of what kind of booze you choose, how much you drink, or how high the alcohol by volume percentage is. Your rate of consumption is also important. Try to avoid downing your first drink in one go. As mentioned earlier, your body can take more than an hour to process the byproducts created by the liver when metabolizing even a small amount of alcohol, so if you can, sip slowly to give yourself a fighting chance of keeping up with the intake.
“The toxicity of alcohol is related to how fast you administer it,” D’Agostino says. “Once you start to feel buzzed, you’re beginning to experience the negative effects. That’s why I stick to a small amount spread out over several hours. Last night, I had a small glass of Merlot while I was preparing dinner and then a second one a couple of hours later. That had no affect on my glucose levels and a minimal impact on my ketones.”
A further consideration is exactly when you should drink. If you’re going to have a glass or two, it’s best to do it a few hours before bed—say, with dinner. The closer your alcohol consumption is to bedtime, the more it’s likely to mess with your sleep and overnight metabolism.
Are There Any Tricks That Would Allow Me To Drink More?
As alcohol is a diuretic, you’ve probably heard the recommendation to pound water before, during, and after drinking to offset the potential dehydration. Like alcohol consumption itself, drinking water is fine if done in moderation. Drinking too much fluid, however, will start flushing electrolytes (magnesium, potassium, and particularly sodium) out of your system, and that can make a hangover even worse. Stick to an eight to 12-ounce glass of water per serving of alcohol and include a pinch of sea salt. The salt contains trace minerals that aid in fluid retention.
Eating food will slow down the absorption of the alcohol, so try to combine your drinking with a main meal. Blood alcohol content can rocket up to three times higher if you don’t have any food in your system. Whereas if you eat just before or while drinking, peak alcohol concentration can be reduced by between 9 and 23%. Be sure you’re eating the right foods too. While a night of drinking can be part of a cheat meal that finds you eating carb foods as well, it’s smarter to stick to keto-friendly fare like meat and vegetables. D’Agostino says fat, protein, and fiber slow the absorption of alcohol and reduce the load it puts on your digestive system. A big meal may also help you feel more satiated, causing you to drink less.
There are exceptions, however. “Personally, I’ve found that a small glass of wine that’s been fermented for a longer period of time to lower the sugar content allows me to operate well on a low-carb diet,” says Greenfield. “I do this particularly when my liver’s glycogen stores are low, which would be when I’m in a fasted state or post-workout. So I break the rules and drink on an empty stomach. I usually have a small glass of wine from Dry Farm Wines or FitVine Wines at 7:30 or 8 p.m. after I’ve exercised and before I eat dinner.” If he’s drinking liquor, Greenfield uses club soda as a low-carb mixer.
Even if you do overdo it at the bar, don’t panic. There’s a simple prescription for getting back on track. “Just drink a couple of glasses of water and go for a brisk walk,” says D’Agostino. “This way you’ll combat the dehydration and increase your circulation and metabolism, which will enable you to clear out the alcohol and get back into ketosis.”