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Everything You Need To Know About The 12-Hour Fast

Intermittent fasting consists of many different methods, from full-day fasts to alternate-day plans, along with the popular method of fasting for 12 hours.

If you’re thinking about starting a 12-hour fast, there’s a lot more to know than just the fact you need to abstain from food for 12 hours a day.

We’ll be covering all aspects of a 12-hour fast, its benefits, and some intermittent fasting rules that you should follow.

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What is a 12-Hour Fast?

When it comes to fasting for weight loss and additional health benefits, there’s a reason why a 12-hour or 12:12 method exists. It requires fasting for half your day and then having an eating window inside the remaining 12 hours.

Not only is it a very flexible eating method, but fasting for 12 hours is also one of the best ways to lose weight, thanks to the calorie deficit that pushes your body through a metabolic switch to burn fat cells at the highest possible rate.

Ketosis, the process of burning stored fat reserves, starts when the body goes without food for a period of 10-12 hours. That’s when ketones are released and your metabolism goes from using sugar to burning fat for fuel.

Thus, restricting calories and fasting for 12 hours is one of the best ways to reduce your body weight and experience the other benefits of intermittent fasting.

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5 Health Benefits When Doing a 12-Hour Fast

Many people are drawn to intermittent fasting because of the various health benefits that are associated with such a diet, on top of the weight loss factor.

In general, intermittent fasting lowers insulin resistance, inflammation, and the risk of heart disease. Plus, someone who fasts can heighten energy production, gut health, and athletic performance— but let’s look at a few more.

1. Helps with weight loss

As previously mentioned, going without food for 12 hours pushes your body to produce ketones and shift into fat-burning, as one of the integral stages of fasting and weight loss.

In addition to a lower daily caloric intake, this fasting period allows the body to switch from burning blood sugar or glycogen, and use fat stores as an energy source instead.

As you might expect, this process is one of the best ways to burn fat away permanently, instead of just targeting water weight, and many dieters can see a real difference in weight loss quite quickly with intermittent fasting.

2. Improves brain health

Tapping into the energy stored in fat reserves is a great way to boost mental clarity and even assist with mental health issues.

Additionally, the physical health of your brain is enhanced by fasting, leading to lower rates of cognitive decline and even reducing brain damage after a stroke.

3. Reduces inflammation in the body

Another of the 12-hour fast benefits is its ability to reduce inflammation, which is a core cause of a variety of diseases, including cardiovascular problems, diabetes, and even cancer.

In particular, studies have shown that a period of fasting and time-restricted feeding with healthy foods on a balanced diet plan actually decreases inflammation in the body.

The calorie restriction associated with fasting promotes better immune responses to inflammatory and autoimmune diseases, both preventing and reversing such illnesses, as well as fixing related hormone issues.

4. Extends lifespan

Extending life should always be a side effect of healthy living and a good diet; intermittent fasting certainly has that advantage.

But is a 12-hour fast enough to gain these benefits? The answer is yes, it absolutely is! Studies show that fasting for long periods is sufficient to enhance circadian autophagy, lengthening life expectancy.

From bettering your muscle mass and metabolism with improved workouts tapping into high-fat energy levels to battling vitamin deficiencies by eating balanced and nutritional food groups, intermittent fasting helps nearly every process in your body.

5. Enhances body detoxification

Because the metabolic system is so important for the entire body, boosting its effectiveness by intermittent fasting is not only good for weight loss but also for organ health and cellular repair for both skin and muscle cells.

By reducing oxidative stress, intermittent fasting removes the same mechanisms that hinder your metabolism and allows for better digestive system health, natural antioxidant protection, and heals gut imbalances.

12-Hour Fast Rules You Should Know About

Let’s discuss exactly what fasting for 12 hours would look like, and how you could structure your schedule around it, as well as some rules to follow.

The 12:12 method is one of the easiest for beginners and those with a busy schedule, as the majority of your fasting window is spent sleeping. Then, on non-fasting days, you can enjoy a meal without calorie restrictions.

For example, to fast for 12 hours twice a week, you would set two days for restriction, such as Tuesday and Friday.

On those days, you could start the feeding window and eat breakfast at around 8 or 9 a.m., with your last meal at that time in the evening. Then, you fast from 8 or 9 p.m. to the next morning, in increments of 12 hours.

To make the process even easier, download the DoFasting app that lets you set up timers for both eating and fasting windows for all IF methods, including 12:12. Thousands of recipes for healthy meals, calorie and water tracking, and a plethora of articles to answer any of your questions!

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Can You Lose Weight by Following a 12-Hour Fast?

In short— yes! Fasting for 12 hours is a great way to convert your metabolism to fat oxidation which in turn helps you lose weight, feel more energetic, and continue burning fat to maintain the weight you already lost.

And because of the calorie deficit, any physical activity you do will just enhance weight loss, when paired with healthy eating plans like a keto diet. The 12:12 fast is a win-win option for many people.

How Long to Fast To See Weight Loss Results?

Safe weight loss generally results in one to two pounds per week, and many dieters see results within a month and a half. At that rate, six weeks equates to around ten pounds of fat loss, which is an entire wardrobe size down!

Of course, fast initial changes are primarily water weight, but once the fat-burning kicks in, you will notice inches disappearing from your waistline.

4 Drinks That Don’t Break a Fast

During the fasting period, you are not allowed solid foods, as the calorie content would push your metabolism out of ketosis. However, there are plenty of other calorie-free drinks that you can enjoy during a fasting window, including the following drinks.

1. Water

Not only is water important for digestion, but it also keeps the hunger pangs at bay by helping you feel full even when fasting.

Plus, because dehydration is a common side effect of intermittent fasting, it’s important to drink water regularly. And, because it has no calories, it doesn’t break your fast!

2. Coffee

Not only does coffee give you plenty of energy, but it’s also a natural appetite suppressant.

However, you can only have black coffee to avoid breaking a fast— adding creamer, sugar, or stevia has enough calories to affect your metabolic process and push you out of fat burning.

3. Tea

Drinking black tea without milk or sugar is also acceptable during intermittent fasting. In fact, several green teas have antioxidants that help burn calories, including tea leaves like jasmine and oolong.

4. Lemon Water

Lemon water is a great refresher, and, as long as you only use pure lemon juice, it does not have enough calories to break a fast. However, stay away from store-bought lemon drinks that have enough sugar and added calories to affect ketosis.

What Can You Eat During the 12-Hour Fast?

During fasting plans, you should always eat a healthy diet with well-balanced meals, including complex and whole grains, lean protein sources, healthy fats, and a variety of fruits, berries, and vegetables.

Items that are highly processed, or full of sugar, trans-fat, or refined starches are not conducive to a healthy diet, particularly when fueling up for fasting 12 hours.

Plus, these foods also can lead to a higher risk of inflammation issues like heart disease and diabetes, which effectively nullifies the benefits of fasting in the first place!

The Best Foods for Breaking a 12-Hour Fast

After your fasting time is over, reintroducing the right foods is crucial to maintaining your success. Avoid eating processed foods or refined sugars, and try not to eat a large meal directly after fasting.

Some of the best options to break a fast include foods that are protein-rich, fresh, and have either complex carbohydrates or fats, such as:

  • Light foods like yogurt, eggs, and smoothies.
  • Salads with lean protein, like fish or chicken.
  • Soup with bone broth, protein, and fibrous vegetables.
  • Whole-grain toast with nut butter or smoked salmon.

What Are the Drawbacks of Intermittent Fasting?

Some people can experience certain side effects of intermittent fasting, which include headaches, fatigue, trouble falling or staying asleep, and nausea. These downsides are short-term, however, and should disappear as the body gets used to IF. the benefits of fasting do outweigh the challenges.

However, certain groups of people should not fast without the advice of a medical healthcare professional, including the following:

  • A history of eating disorders
  • Below 18 years old
  • Breastfeeding or pregnant
  • Diabetics
  • Sleep problems or insomnia
  • Taking certain prescription medications
  • Underlying health conditions

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Amid the various intermittent fasting plans available to dieters, fasting for 12 hours is an effective way to lose weight and enjoy the bonus health effects.

Not only does it kick-start weight loss and boosts the metabolism, but fasting for that long is surprisingly easy to accomplish!

And by following some easy intermittent fasting rules, you too can benefit from better well-being and ultimate weight loss success.


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antika eşya November 18, 2022

Thanks for your article. I have continually seen that the majority of people are desirous to lose weight as they wish to look slim plus attractive. Nonetheless, they do not often realize that there are additional benefits for you to losing weight also. Doctors declare that obese people are afflicted with a variety of diseases that can be directly attributed to their particular excess weight. Thankfully that people who’re overweight in addition to suffering from several diseases are able to reduce the severity of the illnesses by way of losing weight. It is easy to see a progressive but marked improvement in health if even a small amount of weight loss is accomplished.

DoFasting November 22, 2022

We are glad you found it interesting. We see that the majority of people have a goal of weight loss while practicing intermittent fasting, but it can have many other benefits, such as better sleep and overall mood, skin health improvements, reduced risk of diabetes and heart disease, and others.

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DoFasting November 11, 2022

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This is an evidence-based article that includes scientific citations. DoFasting’s professional writers and editors prepared the content, which a team of medical experts verified to be accurate.

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