What Can I Drink When Doing Intermittent Fasting?

Water is the ideal intermittent fasting beverage choice.
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You might already know that you can't eat anything during certain times of your fasting diet, but the less obvious answer is to the question, "What can I drink when doing intermittent fasting?"

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Although you have to completely abstain from food during your fasting window, there are several beverage options that won't break your fast. You can drink as much water (plain or carbonated), lemon water, unsweetened tea and black coffee as you want.



During intermittent fasting, water is the best beverage choice. If you don't want plain water, you can add a little fresh lemon or mint for flavor. You can also drink black coffee and unsweetened tea.

The Basics of Intermittent Fasting

Intermittent fasting is more than just ​not eating​. The goal isn't calorie restriction; the goal is giving your body a break from food so that it can focus its energy on cleansing, rather than digesting.

Your body contains proteins and other structures that constantly become dysfunctional or die. This isn't a bad thing; it's a necessary process for optimal health. However, if these dead tissues aren't cleared out from the body, they can cause cell death, contribute to poor cell and organ function and even become cancerous. Enter a process called autophagy.


The Importance of Autophagy

During autophagy, the body marks damaged parts of cells and unused proteins as potentially harmful. Once your body gets this message, the damaged parts are cleared out. This is a form of cellular cleansing, or detox.

However, if autophagy is never initiated, these dead and damaged proteins accumulate in the body. Fasting is the single most effective way to stimulate autophagy. You can also increase autophagy through exercise and ketosis, but these are not as effective as fasting.


What Can You Drink?

Now that you understand the basics of fasting, the question becomes: What can you ​drink​ while fasting? The best choice is always water​.​ Your water can be plain or carbonated, as long as there's no added sugar. You can also flavor your water with a little bit of fresh lemon.

The goal is to drink at least half of your body weight in ounces. That means, if you weigh 150 pounds, you should drink at least 75 ounces of water in addition to any other fasting-friendly beverages.


Why Is Water So Important?

Staying hydrated helps curb hunger, which makes it easier to stick to your fasting diet, but there are also other numerous health benefits. Drinking water helps lubricate your joints, regulates your body temperature and keeps your digestive system regular.

Water also carries oxygen and other nutrients to your cells, flushes waste out of the body and helps maintain a healthy blood pressure.

Carbonated Water Vs. Flavored Water

Carbonated, or seltzer, water is allowed when intermittent fasting, but make sure you're diligent about reading labels. While true seltzer water doesn't have any added sweeteners, some flavored water drinks do, and it's easy to get confused.

Read the ingredient lists and avoid anything with added sugar or artificial sweeteners, like aspartame or sucralose. Even water flavored with natural no-calorie sweeteners like stevia may kick-start a sugar craving and make it harder for you to stick your fast.

Choose plain seltzer water or seltzer waters that are flavored with natural flavors or fruit essences only.

Can You Only Drink Water?

Although water should be king when it comes to beverage choices, you can also drink:

  • Black coffee
  • Herbal tea
  • Black tea
  • Green tea

Black coffee won't break your fast or take you out of ketosis. In fact, according to a report published in the Journal of Basic and Clinical Physiology and Pharmacology in 2017, caffeine may even increase your metabolism, which will help promote weight loss. Black coffee also helps curb your appetite, which can make getting through your morning fast much more manageable.

But it's important that it's black. If you add cream, milk and/or sugar to your coffee, you'll break your fast.

Go Easy on the Coffee

Although black coffee is OK to drink while intermittent fasting, try not to go overboard. Too much coffee can leave you feeling jittery, anxious and weak, especially if you're sensitive to caffeine. Drinking coffee late in the day can also affect the quality of your sleep.

Plus, you'll be drinking the coffee on an empty stomach, so the caffeine will enter your bloodstream faster than if you'd just had a meal and your stomach was full. Stick to one or two cups a day. If you want more than that, switch to decaf coffee.

Read more:14 Legit Ways Coffee Can Boost Your Health

Should You Avoid Sugary Drinks?

Because of the massive amount of sugar that Americans eat on average, most people have become dependent on glucose, instead of fatty acids, for energy. Every supermarket, grocery store and coffee shop sells an abundance of sugary foods and drinks. When you eat a lot of sugar, and that sugar isn't utilized for energy, your body breaks it down and eventually stores it as body fat.

In addition, the refined sugar found in most beverages digests quickly, spiking both your blood sugar and your insulin levels. It's also highly addictive. Your body doesn't just want more, it ​needs​ more. In fact, according to a review published in Current Opinion in Clinical Nutrition and Metabolic Care in 2013, sugar and sweetened beverages and foods induce reward and craving responses in the brain that are comparable to the responses triggered by addictive drugs, which continue the cycle.

You drink sugary beverages, digest them quickly and store the leftovers as body fat. After the initial spike in blood sugar, you experience a dramatic drop, which prompts you to eat more, and what happens? You store more fat. Because of this, it's best to avoid sugary drinks, like soda, lemonade, fruit juices, sweetened iced tea and even some kombucha, completely, whether you're fasting or not.

Read more:15 Reasons to Kick Sugar

What About Diet Soda?

Diet soda doesn't contain any sugar, calories or carbohydrates, so it may seem like it's OK for fasting, but it's not that simple. Diet soda and other diet drinks are filled with artificial sweeteners, which can drastically increase sugar cravings, making fasting more challenging. Artificial sweeteners can also increase insulin resistance, which makes it harder to lose weight and increase your risk of developing diabetes.

In a 2015 study in the Journal of the American Geriatrics Society, researchers found that people who drank diets sodas tripled their belly fat over a period of nine years. It's best to avoid diet soda and diet drinks completely, but if you include them in your diet, do so in moderation.

Drinking Apple Cider Vinegar

Diluting a small amount of apple cider vinegar in 8 ounces of water won't break your fast. In fact, it might actually be a really good idea. According to a study in the Journal of Medicinal Food in 2018, apple cider vinegar can lead to positive metabolic changes that help promote weight loss. Drinking apple cider vinegar every day may also reduce total cholesterol, triglycerides and LDL or "bad cholesterol" levels.

Make sure to dilute it in water before drinking it, though. The acetic acid in apple cider vinegar is potent and drinking it undiluted may damage tooth enamel.

What Can You Eat?

During your fasting window, you can drink as many of the approved beverages as you want, but you can't eat anything. Eating provides calories and starts digestion, two things that break your fast. When your fasting window ends, and you enter your feeding window, it's best to make food choices that keep your blood sugar levels stable.

Although there's no specific dietary recommendation when intermittent fasting, many people choose to combine it with a low-carb, ketogenic diet. When it's time to eat, include foods that are high in good fats and low in carbohydrates. That means eating nuts, seeds, vegetables, avocado, olives, meat and fish, while avoiding whole grains, fruits, starchy vegetables, sugary drinks and anything processed.

Processed foods are usually packed with sugar additives and other undesirable ingredients that improve the taste but negatively affect your health. Even if "sugar" isn't listed on the label of ingredients, chances are it contains a substitute in some form. Whether it's sucrose, dextrose, high-fructose corn syrup or something similar, these ingredients can have the same (or worse) effects as sugar.

Fasting and Weight Loss

Intermittent fasting isn't a regimen built around limiting calories (although it's likely that your calorie intake will be restricted naturally since you're going a period of time without eating), but it can promote weight loss in a big way. Fasting gives your metabolism an overhaul. It works on the same principles as a ketogenic diet. By restricting food (and carbohydrates), you'll switch your body from burning glucose for energy to burning stored body fat.

According to a study in Translational Research in 2014, intermittent fasting can reduce your weight by 3 to 8 percent over three to 24 weeks. A systematic review in Molecular and Cellular Endocrinology in 2015 confirmed these results by reporting that, on average, participants following a fasting diet lost between 7 and 11 pounds in 10 weeks.

Establishing an Intermittent Fasting Plan

So what's the ideal way to design an intermittent fasting plan? It depends on your schedule and what works best for you, but a good template to start is:

  • Start your day off with a glass of water. Your body is made up of around 60 percent water, and every one of your cells needs it to function.
  • After your water, have a cup of black coffee or tea, if you'd like. But remember, no sugar or cream/milk.
  • Continue fasting for your chosen length of time (the average is 16 hours of fasting combined with 8 hours of eating)
  • When it's time to eat, keep your intake of sugar and other carbohydrates low and eat plenty of fiber-rich, nutrient-dense whole foods.
  • Continue drinking water throughout the course of the day until you reach your goal intake.