Does Taking Vitamins Break Intermittent Fasting?

Does Taking Vitamins Break Intermittent Fasting?

Written by Andrew Brewer. ⚕️Reviewed and fact checked by our medical team.

Does Taking Vitamins Break Intermittent Fasting?

When it comes to intermittent fasting, few things are cut and dry. Some drinks can be had while intermittent fasting whereas others can’t. Some intermittent fasting methods allow you to have up to 50 calories while fasting, other’s say one calorie breaks a fast. There are plenty of debates about what is effective and healthy, and what can cause harm to the body.

One of the most confusing topics regarding intermittent fasting is whether vitamins will break your fast or not. As with all categories, some will and some won’t. However, the difference can come down to the individual vitamin whereas with drinks you can at least categorize them. General rules do apply with vitamins regarding whether or not they break your intermittent fast, but it pays to be vigilant and check before taking them.

Let’s take a look at what makes a vitamin okay to have whilst intermittent fasting. It can be tough deciding whether or not a vitamin breaks your fast, so always check the ingredients before taking the vitamin.

Key Takeaways

  • The answer to whether taking vitamins breaks intermittent fasting depends on the properties of the vitamin itself, such as whether it contains calories, carbs, or triggers insulin production.
  • Some vitamins must be taken with food, which will likely break a fast, while others can be taken with water and may be okay if they don’t exceed the calorie or carb threshold.
  • The specific rules of one’s fasting plan play a role, as some methods allow for more calories than others, and some fasters may believe that even 1 calorie breaks a fast.
  • To ensure you don’t break your fast, always check the ingredients of vitamins before taking them and take them during your eating window if they must be taken with food.

It Depends on Each Vitamin

The vitamin you’re taking could have certain properties that will break your fast. Some vitamins can trigger insulin production in the body which ultimately breaks a fast. Other vitamins contain calories and carbs that can easily surpass even the most lenient intermittent fasting limits. Gummy multivitamins even contain enough sugars to break your fast. Protein powders are designed to trigger an insulin response which wakes up your system and breaks your fast.

Multivitamins that don’t contain sugar or calories should be fine to take as they don’t offer any bodily responses that ultimately break your fast. Fish oils, creatine, probiotics, and prebiotics should also be safe to take while intermittent fasting. They don’t contain enough calories to individually break your fast.

Taken With Food

Some vitamins must be taken with food for your body to avoid the potential side effects. If the vitamin requires food, then it’s probably going to break your fast. Even if the vitamin itself doesn’t contain calories or carbohydrates, the food that must accompany it certainly will. In general, if you must take food with the vitamin, try to do so during your eating window.

Taken With Water

Vitamins that should be taken with water are likely okay to have while intermittent fasting. If the calories and carbs of the vitamin are below the threshold, then it should be okay. Water is necessary while fasting, so it won’t break your fast alone.

It Depends on the Fasting Method

It’s also important to take the method of fasting into account. How strict the rules are will certainly play a part in deciding whether to take vitamins while intermittent fasting. Some intermittent fasting methods allow up to 100 calories which provide ample room for vitamin consumption. Very few vitamins pack more than 100 calories in a single pill, so you should be okay to have your vitamins.

However, there are also some intermittent fasters who believe that 1 calorie is enough to break a fast. If you eat or drink anything that isn’t water while intermittent fasting, you could end up breaking the fasting state and losing all progress. If you’re partaking in this form of intermittent fasting, then a vitamin will most certainly break your fast.

There are many different factors that go into whether or not taking vitamins will break your fast. From the vitamin itself to your beliefs on intermittent fasting, there is no concrete answer. Just make sure to check the ingredients before taking the vitamin to know for sure if it will cross your intermittent fasting threshold.

Don’t forget to check our recommended fasting apps here to make your intermittent fasting journey easier.


  • Can I take vitamins during intermittent fasting?

It depends on the type of vitamin. Generally, taking vitamins that contain calories can break your fast, while taking calorie-free vitamins is unlikely to significantly impact your fasting results.

  • Which vitamins are calorie-free?

Most B vitamins, vitamin C, and vitamin D are calorie-free and, therefore, can be taken during intermittent fasting without breaking your fast.

  • Which vitamins are not calorie-free?

Fat-soluble vitamins such as A, E, and K, as well as some supplements like multivitamins and omega-3 supplements, may contain calories and can break your fast.

  • Can I take medication during intermittent fasting?

Taking medication during intermittent fasting is generally okay, but you should consult your doctor to determine the best course of action.

  • Can taking vitamins during intermittent fasting affect weight loss?

It depends on the type of vitamin and the number of calories it contains. Calorie-free vitamins are unlikely to affect weight loss, while vitamins that contain calories can impact your calorie intake and potentially hinder weight loss.

Andrew Brewer

Andrew Brewer

Andrew Brewer started to give people the guidance that he never received when he was first starting. His goal is to make your goals achievable and to offer you only the best fasting apps that the internet has to offer. You're not on your own - Andrew and the entire family of reviewers at are here with you every step of the way!