What Is Dirty Fasting and Is It Effective?

Dirty fasting

Don’t be concerned about the term dirty; while it may appear to be a negative connotation, it is not. Dirty fasting is a new practice adopted by certain people who engage in intermittent fasting.

In this post, we’ll go over the fundamentals of dirty fasting, including how it works and how effective it is.

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What is dirty fasting?

There is no unified definition of dirty fasting, and the term is not used in the medical community.

Dirty fasting is a modern term for a type of intermittent fasting in which you can consume some calories during a fasting window.

Normally, only beverages with zero or very few calories – such as water, black coffee or tea, and unsweetened herbal tea – are consumed during fasting hours, which has become known as “clean” fasting.

So dirty fasting is in contrast to traditional fasting or “clean” fasting which bans all foods and calorie-containing beverages during the fasting window.

An exception to this is modified alternate-day fasting, in which you consume a minimal quantity of calories on “fasting” days, often 500 or so.

People who practice dirty fasting will often consume up to 100 calories throughout their fasting window. This may be adding a little creamer to your coffee or sipping on some delicious bone broth. Maybe you put zero-calorie sweeteners in your tea or drink zero-calorie soda.

There is no human clinical research on the health benefits of dirty fasting, but some people who practice it claim that the method provides similar benefits to clean fasting.

Proponents of dirty fasting say that consuming a portion of calories does not technically break a fast and that this form of fasting makes it easier to stick to a fasting regimen.

Pouring milk in black coffee

What can you consume during a dirty fasting window?

Here is a list of foods that you can have during a dirty fasting window. Add them to beverages for flavor if you want to try dirty fasting.

  • 1 tbsp. coffee creamer – 20 calories, 1.7g carbs (source)
  • 1 tbsp. whole milk – 9 calories, 0.7g carbs
  • 2 tbsp. almond milk – 7.3 calories, 1g carbs
  • 1 tbsp. agave syrup – 60 calories, 16g carbs
  • 1 tbsp. honey – 64 calories, 17g carbs
  • 1 tbsp. maple syrup – 52 calories, 13g carbs
  • 1 pack stevia (pure) – 0 calories, 0g carbs
  • 1 pack splenda (sucralose) – 3 calories, 0.9g carbs
  • 1 tbsp (14 grams) grass-fed butter – 100 calories, 0g carbs
  • 1 tsp MCT oil – 38 calories, 0g carbs, 100% fat
  • 1 cup bone broth – 40 calories, 0.6g carbs
  • water + juice of 1 lemon – 14 calories, 0g carbs

In summary, dirty fasting allows diet drinks, sweeteners, and other additions to tea and coffee as long as the total number of calories consumed does not exceed 100.

Is dirty fasting effective?

If losing weight is your goal, dirty fasting can help. This is simply because you are likely to consume considerably fewer calories while dirty fasting than you would during a usual day of eating without time restrictions.

Many people, however, practice intermittent fasting for the additional benefits it provides, such as promoting autophagy, reducing insulin resistance and blood sugar levels, and so on. (source)

When you practice dirty fasting, you consume a minimal amount of calories during your fasting periods.

Experts agree that consuming 100 calories reduces autophagy to absolute baseline levels. As a result, the majority of the rejuvenating benefits of fasting are negated by this calorie intake.

Autophagy is the body’s way of cleaning out damaged cells in order to regenerate newer healthier cells. You can find additional information about autophagy here.

There is no evidence that dirty fasting is as successful as traditional intermittent fasting methods which involve total calorie restriction during fasting periods in achieving these potential benefits.

If you drink your coffee with milk or have a cup of bone broth during your fasting window, you are technically breaking your fast, despite the fact that you are consuming a minimal quantity of calories.

Although most experts agree that having zero calories is the best method to ensure that a person is actually fasting, zero-calorie beverages such as black coffee and unsweetened tea are unlikely to break a fast.

More on what to drink on IF without breaking your fast here.

Dirty fasting may not have the same impact as clean fasting. Again, there has been no research focused on dirty fasting.

It may be beneficial for weight loss, although persons who practice dirty fasting may not technically be in a fasted state during fasting windows. This is especially true if they are taking more calories than they realize, which means they will miss out on the other benefits of fasting, especially autophagy.

The only way to ensure that you’re in a fasted state is to abstain from all calories during a fasting window. As a result, dirty fasting may not produce similar results as clean fasting.

Dirty vs. clean fasting

Dirty fasting may be a good approach to get started with intermittent fasting, and when you’re ready, you can switch to the cleaner method.

By following the dirty method, you can approach the eating window with less anxiety. You may even be able to finish extra hours of fasting as a result of the additions you add to your coffee and other beverages.

Depending on how you feel on any given day, you can use a combination of “clean” and “dirty” fasting. The most important factor to consider is that the path you choose is one that you are comfortable with and can stick to.

Because there is no research to back up the dirty fasting approach, it is recommended to choose an intermittent fasting method that is supported by research.

The only way to be sure that you’re in a fasted state is to consume no calories during your fasting period. This is what it’s called clean fasting – you consume only water, black coffee, and unsweetened tea during your fasting window.

The negligible number of calories in beverages like black coffee and herbal teas, according to most experts, won’t break your fast.

Always get the advice of a professional before making any dietary changes. A certified dietitian can advise you on whether intermittent fasting is the best option for your specific needs and health goals.

The takeaway

The most important thing to understand about dirty fasting is that it includes consuming a small number of calories throughout fasting windows. The number of calories consumed during non-eating hours distinguishes between clean and dirty fasting. Clean fasting is when you consume no calories during the fasting period.

Proponents of dirty fasting say that this method makes it easier to stick to fasting regimens. However, there is no scientific evidence to back up this claim. Technically, you can break your fast if you consume calories, no matter how small the number.

It is entirely up to you whether you will try dirty or clean fasting. But, before you do that, do some research to learn about the fundamentals of fasting, intermittent fasting methods, and the potential side effects of intermittent fasting.

Every individual is unique. So, while one eating style may be beneficial to one person, it may not be beneficial to another.

Before making any dietary changes, it is always recommended to consult with a licensed nutritionist or your doctor.

Dirty fasting: What is it and how it works

Disclaimer: All the information on this website is for educational purposes only. Nothing on this website should be considered as health or medical advice. Always consult with a doctor or trusted health professional before following any dietary, nutritional, or herbal recommendations.

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