Caffeinated and Alcoholic Drinks in a Low Carb Diet

A Look at What Counts as Fluid Intake on Your Low Carb Diet

Close up of hands holding cup of coffee in cafe
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Low carb diets have guidelines for fluid intake. While the conventional wisdom is that water is best, drinking only water may not be a reality for people on low carb diets. You can find conflicting things about whether caffeinated and alcoholic beverages should "count" in the daily water intake recommended by low carb diets. Here we discuss whether you should be counting all liquids toward your water intake.

We will also cover how these counts can affect your overall adherence to the low carb diet plan.

Caffeine and Dehydration

It was once thought that caffeinated beverages would dehydrate a person to the point where the water in them "wouldn't count." However, multiple studies have shown that the amount of caffeine in most popular beverages does not keep the body from absorbing the water in them. Therefore, from the standpoint of hydration, caffeinated beverages, including tea and coffee, can count towards the total.

The Alcohol Difference in a Low Carb Diet

Alcoholic beverages are a different story, however when it comes to counting liquid intake. Alcohol increases urination fairly dramatically. Depending upon the alcohol concentration of the drink, it could even cause you to eliminate more water than the drink contains. So alcoholic beverages should not count towards the total fluid intake, and you might even want to have an extra glass of water.

If carbs are an issue, there are no carbs in the dark liquors, such as cognac, brandy, scotch or whiskey. Vodka, rum, gin and tequila is also no carbs. These are for the original, unflavored versions. For flavored spirits (including flavored vodkas and some dark/coconut rums), always check up on nutritional information before consuming as they often contain carbohydrates.

If you opt for a mixed cocktail, you will have carb counts and may not know what they are.

To ensure you don't add sugar or calories, ask for soda water, diet sodas, diet tonic water, seltzer water, sugar-free energy drinks and sparking water. 

Fluid Intake Schedule

Because coffee and tea count towards your allotment of water for the day, try and figure out a schedule of drinking fluids just as you would food. Some people start with the amount of water they want to consume a day and break that down into four times where you'd drink that amount over a period of time.

For example, if you want to drink four quarts a water a day, you'd designate four times, equally spaced throughout the day, to drink in a span of 30 minutes each time. Schedule your water drinking time at least an hour after your meal.

 While most fluids allowed by your diet can count toward your total fluid intake, plain water is always preferred. If you're looking to spice up your daily water intake, check out these awesome alternatives to plain water.


Armstrong, LE. "Caffeine, body fluid-electrolyte balance, and exercise performance." Int J Sport Nutr Exerc Metab. 12/2 2002.

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