Last Updated on January 28, 2023 by Lori Geurin
When it comes to intermittent fasting, there are a lot of questions about what you can and cannot do. One common question is whether drinking diet soda breaks a fast. Let’s explore what the research says about artificial sweeteners and fasting. Does diet soda break a fast?
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- Artificial Sweeteners and Intermittent Fasting
- What is intermittent fasting?
- What Is Diet Soda?
- What drinks can you have while intermittent fasting?
- Drinks To Avoid While Intermittent Fasting
- Can you drink Diet Coke when fasting?
- Will zero-calorie drinks break a fast?
- Final Thoughts About Diet Soda In Your Fasting Window
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Artificial Sweeteners and Intermittent Fasting

There are a few things to consider regarding artificial sweeteners and fasting. First, it’s important to remember that intermittent fasting aims to give your body a rest from digesting food, allow it to burn stored energy, and enjoy the benefits of autophagy. So, if you’re consuming artificial sweeteners, you still take in a few calories.
Second, artificial sweeteners can cause an insulin response in the body, which can interfere with the fasting process. When insulin levels are high, the body is more likely to store fat rather than burn it for energy.
Finally, artificial sweeteners can also cause cravings and disrupt hunger cues.[*] This can lead to overeating and weight gain.
What is intermittent fasting?
Intermittent fasting is an eating pattern where you cycle between periods of eating and fasting. It can be used to lose weight, improve insulin sensitivity, and reduce inflammation. There are many different ways to do intermittent fasting, but the most common is the 16/8 method, which involves fasting for 16 hours and eating during an eight-hour window.
If you’re considering intermittent fasting, talk to your doctor first. Intermittent fasting is not for everyone, and it’s essential to ensure it’s safe for you before starting.
Now that we’ve answered the question, “Does diet soda break a fast?” you can make an informed decision about whether or not to include it in your intermittent fasting plan. Remember, the goal is to consume zero calories and give your body a rest from digesting food. If artificial sweeteners interfere with that goal, avoiding them is best.

What Is Diet Soda?
Diet soda is a type of soda that contains artificial sweeteners instead of sugar. These artificial sweeteners can include aspartame, sucralose, and saccharin. Diet soda is often marketed as a healthier alternative to regular soda because it doesn’t contain many calories or sugar. However, diet soda is not necessarily healthy. In fact, it can actually be quite harmful.
The Risk Associated With Diet Sodas
Artificial sweeteners have been linked to weight gain, insulin resistance, cravings, metabolic syndrome, and type 2 diabetes.[*] They can also disrupt hunger cues, leading to overeating. Diet soda also contains a plethora of potentially harmful artificial chemicals.
What drinks can you have while intermittent fasting?
Here’s a list of some of the best drinks to have while intermittent fasting:
- Black coffee
- Unsweetened green tea
- Water
- Sparkling Water
- Unsweetened herbal tea
RELATED: What Is Clean Fasting And How It’ll Boost Your Fasting Results

Drinks To Avoid While Intermittent Fasting
Wondering what drinks or liquids to avoid when you’re in your fasting window? Here’s a list of drinks to avoid:
- Soda
- Fruit juice
- Sports drinks
- Sweetened coffee or tea
- Alcohol
- Milk
- Fruit smoothies
- Bone broth
- Apple cider vinegar
- Sweetened drinks like soda
- Diet drinks
Remember, the goal of intermittent fasting is to consume zero calories. So, if you’re looking for the best results, stick to water, black coffee, and unsweetened tea.
RELATED: Healthy Coffee Drink Recipe (With Coconut Oil)
Can you drink Diet Coke when fasting?
The simple answer is no. I do not suggest it. Diet Coke (and other diet sodas) contains artificial sweeteners, which can cause an insulin response in the body, disrupt hunger cues, and lead to overeating. So, if you’re trying to intermittent fast for better fasting results, it’s best to avoid diet soda altogether.
Will zero-calorie drinks break a fast?
It depends. Black coffee, water, sparkling water, and unsweetened tea are all okay to consume while fasting. However, a calorie-free drink containing artificial sweeteners can cause an insulin response in the body and disrupt hunger cues. So, if you’re trying to intermittent fast for better fasting results, it’s best to avoid zero-calorie drinks that contain artificial sweeteners.
RELATED: Intermittent Fasting Plateau: 9 Tips To Boost Your Weight Loss

Final Thoughts About Diet Soda In Your Fasting Window
So, what’s the bottom line? If you’re trying to intermittent fast for weight loss or health benefits, it’s best to avoid diet soda and other artificial sweeteners. Stick to water, herbal tea, and black coffee while fasting. This will help you stay on track and achieve your goals. You’ve got this!
What do you think? Have you tried intermittent fasting? What has been your experience? Does diet soda break a fast? Share in the comments below!