Water is your best friend on keto, but it’s far from your only option. The key rule is simple: stick to drinks with little to no sugar and minimal carbohydrates, typically under 1 to 2 grams of net carbs per serving. Beyond that, what you drink on keto can actually help you solve some of the diet’s most common problems, from electrolyte depletion to energy dips.
Water and Electrolytes Come First
Keto causes your kidneys to flush more sodium and water than usual, especially in the first few weeks. This is why many people feel foggy, fatigued, or headachy early on, a cluster of symptoms often called “keto flu.” Plain water is essential, but it’s not enough on its own. You need to actively replace electrolytes that your body is dumping at a faster rate.
The targets are higher than what most people expect: 4 to 6 grams of sodium per day, 3.5 to 5 grams of potassium, and 400 to 600 milligrams of magnesium. For context, mainstream dietary guidelines suggest limiting sodium to about 2.3 grams, so keto roughly doubles that need. You can hit these numbers by salting your food generously, drinking broth, or adding electrolyte powders to your water. Look for electrolyte mixes sweetened with stevia or monk fruit rather than sugar. Avoid sports drinks like Gatorade or Powerade, which typically contain 20 or more grams of sugar per bottle.
Coffee and Tea
Black coffee and unsweetened tea, whether green, black, herbal, or iced, are zero-carb staples on keto. Caffeine can even mildly boost fat oxidation, which complements what your body is already doing in ketosis.
The trick is what you add to them. A splash of heavy cream (about a tablespoon) adds less than half a gram of carbs and gives you a dose of fat. Half-and-half is a step up in carbs but still manageable at roughly 0.6 grams per tablespoon. What you want to avoid is flavored creamers, which can pack 5 to 15 grams of sugar per serving, and sweetened coffee shop drinks that can easily exceed 40 grams of carbs.
For sweetening, stevia and monk fruit extract are the safest choices. Neither raises blood glucose, and both are generally well tolerated. Erythritol, a sugar alcohol, is another popular option with a glycemic index of zero. Sucralose is trickier. A controlled trial published in The American Journal of Clinical Nutrition found that moderate sucralose consumption over two weeks decreased insulin sensitivity by about 18% in healthy adults. That doesn’t necessarily kick you out of ketosis, but it works against the metabolic improvements many people are pursuing with keto in the first place.
Bone Broth
Bone broth is one of the most underrated keto drinks. A cup of beef bone broth has about 39 calories and 9 grams of protein with virtually zero carbs. It’s also naturally rich in sodium, which makes it a practical way to meet those higher electrolyte targets without supplements. Many people on keto sip a warm cup in the morning or between meals, especially during the first week when keto flu symptoms tend to peak. Homemade versions give you control over salt levels, but store-bought works fine as long as you check the label for added sugars.
Which Milks Work on Keto
Regular cow’s milk contains about 12 grams of carbs per cup, mostly from lactose. That’s a significant chunk of a 20 to 50 gram daily carb budget, so most keto dieters swap it out. Your best options per cup (about 240 milliliters):
- Unsweetened almond milk: roughly 1.6 grams of carbs, 3.7 grams of fat, and 1.6 grams of protein. The lowest-carb option by a wide margin.
- Unsweetened soy milk: about 3.1 grams of carbs, 5.1 grams of fat, and 8.5 grams of protein. The highest protein of the plant milks.
- Unsweetened coconut milk (carton): around 7 grams of carbs, 5 grams of fat. Higher in carbs than almond or soy, so measure carefully.
- Oat milk: roughly 12 grams of carbs per cup. This is not keto-friendly, even in unsweetened versions.
The word “unsweetened” on the label is non-negotiable. Sweetened versions of any plant milk can double or triple the carb count.
Sparkling Water and Diet Soda
Plain sparkling water and mineral water are zero-carb and perfectly fine. Brands like Topo Chico and Perrier also contribute small amounts of minerals. Flavored sparkling waters (La Croix, Bubly, Waterloo) that use natural flavors without sweeteners or calories are also safe choices.
Diet sodas are more nuanced. They contain zero carbs and won’t directly raise blood sugar, so technically they don’t break ketosis. But the sucralose found in many diet drinks (Splenda-sweetened options, some Diet Coke varieties) may reduce insulin sensitivity over time, based on the clinical evidence mentioned above. Aspartame, used in classic Diet Coke and Diet Pepsi, hasn’t shown the same insulin sensitivity effect in humans, though animal studies suggest it can alter gut bacteria. If you drink diet soda, treating it as an occasional thing rather than a daily habit is a reasonable approach.
Adding MCT Oil to Drinks
MCT oil is a concentrated fat derived from coconut oil that your liver converts quickly into ketones. Adding it to coffee, tea, or smoothies is a popular way to boost energy and deepen ketosis. The classic “bulletproof coffee” is just brewed coffee blended with MCT oil and butter or ghee.
Start small. Your digestive system needs time to adjust, so begin with 1 teaspoon (5 milliliters) per serving. After about a week, you can gradually increase to 1 tablespoon (15 milliliters) per serving, up to 3 or 4 times a day. Jumping straight to large doses commonly causes stomach cramps and diarrhea.
Flavoring Water Without the Carbs
If plain water bores you, fresh lemon or lime juice is a simple fix. A fluid ounce of lemon juice, roughly two tablespoons, contains only about 1.2 to 1.5 grams of carbs. A squeeze into your water bottle is a fraction of that. Fresh mint, cucumber slices, or a pinch of salt with citrus all add variety at negligible carb cost.
Apple cider vinegar diluted in water (1 to 2 tablespoons per glass) is another common keto drink. It has less than 1 gram of carbs per tablespoon and some evidence for supporting blood sugar stability, though the taste takes getting used to.
Kombucha: Check the Label Carefully
Kombucha sits in a gray area. The fermentation process eats up some of the sugar used to brew it, but not all. Plain, low-sugar brands typically contain 2 to 6 grams of sugar per 8-ounce serving. That can fit within a keto budget if you’re careful. But high-sugar or fruit-flavored commercial brands can run 10 to 15 grams per serving, which is a significant hit. Always check the nutrition label, because “kombucha” alone tells you very little about the sugar content.
Alcohol on Keto
Distilled spirits like vodka, gin, whiskey, and tequila contain zero carbs when consumed straight or with a zero-calorie mixer like soda water. A dry red wine has about 1 to 2 grams of carbs in a standard glass. Light beers vary widely but can range from under 5 grams to around 10 grams of carbs per pint, so check the brand.
The carb count isn’t the whole story, though. Your body treats alcohol as a priority fuel source. While it’s processing alcohol, fat burning pauses. This doesn’t knock you out of ketosis permanently, but it slows the process. You’ll also feel the effects of alcohol faster on keto because lower glycogen stores mean there’s less to buffer the absorption. One drink on keto can feel like two or three on a standard diet.
Drinks to Avoid
Regular soda, fruit juice (even 100% juice), sweetened iced teas, energy drinks with sugar, smoothie shop blends, and milkshakes are all off the table. A single 12-ounce can of Coke contains 39 grams of sugar. Orange juice has about 26 grams of carbs per cup. Even drinks marketed as “healthy,” like açaí bowls or cold-pressed juices, routinely exceed 30 grams of carbs per serving. The simplest rule: if the label shows more than a few grams of sugar, skip it.