Can You Take Vitamins While Fasting? Do Vitamins Break a Fast?

Can You Take Vitamins While Fasting? Do Vitamins Break a Fast?
Dr. Mario Ost

Dr. Mario Ost | Author

Dr. Mario Ost is a renowned nutrition scientist, researcher and lecturer, deeply invested in enhancing our basic understanding on mitochondrial fitness, muscle health, and endocrine organ crosstalk in sports, aging and metabolic diseases. He's a founder of a young athlete health academy and serves as a scientific advisor at Fastic, focusing on personalized nutrition concepts, fasting-mimicking food-components (autophagy-inducers) and benefits of exercise for metabolic homeostasis and healthy aging. As a devoted father and pioneer, Dr. Ost is shaping a future where elite athletes achieve peak performance and obese patients regain their metabolic and muscle health through an evidence-based approach on personalized training and nutrient timing.

Vitamins can’t break a fast. It depends on the kind of vitamin supplements, as some have additives and sugars that can interfere with your fast. Also, some vitamins are best taken with food, so those vitamins should be avoided while fasting. Keep in mind, that a healthy, well-balanced plant-forward diet that covers your individual daily energy requirements provides all vitamins and micronutrients in optimal doses. Food first! 

A Quick Word on Vitamin Supplements

Vitamins are micronutrients that are essential for a variety of body functions. They help keep your organs healthy, strengthen your immune system, and are even essential for energy metabolism. 

While you can get them through food, under certain circumstances it might be beneficial to supplement them to avoid deficiencies. For instance, if you live in a cold, dark climate with very few sunny days, you will most likely benefit from a Vitamin D supplementation. So, taking a supplement will help ensure you have enough. 

There are six main vitamins: A, B, C, D, E, and K. There are many B vitamins, such as folate (Vit B9), thiamine (Vit. B1), biotin (Vit. B7), and cobalamin (Vit. B12). 

Vitamin supplements are either water-soluble or fat-soluble

  • Water soluble vitamins include B vitamins and C. These can dissolve in water and can be taken without eating food first.

  • Fat-soluble vitamins include A, D, E, and K. These are taken with foods containing fat so your body can absorb them. 

Although you can supplement vitamins, it’s best to get them through healthy foods. If you want to learn which foods are best for intermittent fasting, the Fastic app can answer all your questions. 

can you take vitamins while fasting

Can Vitamin Gummies Break Your Fast?

Gummy vitamins often contain sugar and other ingredients that can result in an insulin response and break a fast. Regardless of the type of vitamin you’re taking, if the gummies contain sugar, they should be avoided during a fast. 

While gummies are easy to consume, they are generally high in sugar and low in nutrients and fibers. Therefore, they should be avoided, especially if you’re trying to lose weight. 

Can Fat-Soluble Vitamins Break Your Fast?

Fat-soluble vitamins may not break your fast if they contain low or no carbohydrates. However, fat-soluble vitamins should be consumed during the eating window, as these are supposed to be taken after a meal. 

You see, fat-soluble vitamins are best absorbed with a little fat. So if you take them on an empty stomach in your fasted state, your body won’t readily absorb them. 

Take fat-soluble vitamins A, D, E, and K with food, ideally after your main meal of the day. 

What About Water-Soluble Vitamins?

Water-soluble vitamins can be absorbed with or without food. So you can take them while you’re intermittent fasting. 

That said, it’s important to pay attention to the contents of the vitamin supplements. Gummies and chewables may contain ingredients that can potentially break your fast. You don't want to activate your insulin response if you’re intermittent fasting for weight loss or any other benefit, for that matter. 

Can You Take Multivitamins While Intermittent Fasting?

Multivitamins can be taken during a fast, as they’re typically very low in calories. However, it depends on the type of multivitamins. That’s because some multivitamins may contain both water and fat-soluble vitamins. In such a case, taking them during your eating window would be better so the food can help dissolve the fat-soluble vitamins and optimize their absorption. 

Pay attention to what vitamins the multivitamin supplement offers and whether it contains additives like sugar. Gummy and chewable multivitamins should be avoided during intermittent fasting, as they contain carbs that may interfere with your fast. 

What Is the Best Time to Take Vitamin Supplements?

The best time to take vitamins depends on what vitamin you’re taking. Water-soluble vitamins can be taken at any time, as they only require water to be absorbed by the body. So you can even take them on an empty stomach. 

Fat-soluble vitamins and multivitamins are best taken after a meal. Ensure that your meal contains some healthy fat components to help break down and absorb these vitamins. 

Some vitamin supplements like vitamin B12 should ideally be taken in the morning. These vitamin supplements support energy metabolism, so taking them in the morning will help boost your energy levels during the day. 

Many of us struggle to take supplements on time or don’t take them regularly. The Fastic app, designed to make intermittent fasting easier, can be used to set reminders for taking supplements like multivitamins. 

Take Your Vitamins with Care

Most vitamins can be taken any time of the day, even in a fasted state. However, it all comes down to the supplements' actual vitamins and other nutrients. Taking water-soluble vitamins during a fast may help increase your energy. 

Keep in mind that your body can only absorb a finite amount of vitamins, especially water-soluble ones. Any excess vitamins will be flushed out with the urine. 

Disclaimer: It’s advised to speak with a health professional before beginning intermittent fasting or a diet program. There may be side effects for people with certain medical conditions.


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