New Research Findings On the Best Fasting Length for Fat Loss (12 vs 36 vs 72 Hours)

Check out the new findings on scientific studies about how long and how frequently you should be fasting if your goal is fat loss.

BOXROX has previously written about the differences between prolonged fasting and intermittent fasting. And now, there is a little bit more light on the debate of whether one is better than the other, as Thomas DeLauer explains.

Thomas DeLauer is a celebrity trainer and health author. His YouTube Channel has 3 million subscribers and he has been on the cover of numerous international magazines.

Check out below the findings of the research and what you should keep in mind when fasting for fat loss.

New Research Findings on Best Fasting Length for Fat Loss

DeLauer says that the ultimate for fat loss is maintaining your metabolism high. “It should be priority number one.” Other subcategories of that priority would include maintaining muscle, adequate protein intake and other fitness goals you might have.

“We want to avoid anything that dramatically slows down our metabolism,” Delauer says.

With that in mind, he talks about a few studies conducted over the years, and one fairly recently, that analysed different types of fasting: 12 hours, 36 hours, and 72 hours fasting periods. The studies he mentions can be found here, here, here, and here.

One paper found out that restricting your feeding window to 36 hours actually increased the basal metabolic rate (the rate of energy expenditure) of a person. On the other hand, 12 hour fasting period lower the BMR a little, while the 72 hour fasting period saw practically no change in the metabolic rate compared to the 36 hours.

Cross-referencing with other studies that looked more into continuous caloric restriction, it was found that restricting calories too often for too long can slow down the metabolism, which is the opposite of what you want if you are looking to lose body fat.

On the other hand, more infrequent, longer fasts will actually increase metabolism, so the thing is about finding the sweet spot of fasting long and frequent enough for fat loss to occur without slowing down metabolism.

What this all means is that, if you are fasting daily and putting yourself in a caloric restriction phase, it takes about 2 to 3 weeks for your metabolism to slow down.

However, if you use fasting to shock your body, you can increase your metabolism. “If you were to fast maybe two days per week, like a 24-hour fast or one day a 36-hour fast, you can actually increase metabolic rate,” DeLauer says, explaining that it is not a chronic caloric restriction.

The idea is not that you do 24 hours fast or 36 hours fast weekly to lose weight, but if you are doing daily some kind of intermittent fasting such as the 16:8, you have about 2 weeks before you need to take a break from your fasting or reduce the fasting days.

Check out DeLauer’s video below for more detailed information on the subject.

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Intermittent Fasting Mistakes That Make You Gain Weight

There are a few fasting tactics a person can approach. The most common are:

16/8 – fast for 16 hours, eating window for 8 hours every day.
Warrior diet – fast for 20 hours, eating window for 4 hours every day.
OMAD – one meal per day only.
Alternate day fasting – fast for 24 hours, eating window for the following 24 hours, repeat.
5:2 diet – fast for 2 days, eating window for the following 5 days. The 2-day fast window does not have to be consecutive back-to-back.

Some of the benefits of intermittent fasting include:

Weight loss: Intermittent fasting can help individuals lose weight by reducing the number of calories they consume. By limiting the hours during which you can eat, you naturally consume fewer calories.
Improved insulin sensitivity: IF can help improve insulin sensitivity, which is important for maintaining healthy blood sugar levels.
Reduced inflammation: Studies suggest that IF may help reduce inflammation in the body, which is linked to a number of chronic health conditions.
Improved heart health: Some studies have found that IF may help reduce the risk of heart disease by lowering blood pressure, improving cholesterol levels, and reducing oxidative stress.
Increased longevity: Some animal studies suggest that intermittent fasting may help increase lifespan, although more research is needed in humans to confirm this.

What Happens To Your Body If You Eat Only One Meal a Day for 30 Days?

To burn fat, you need to create a calorie deficit by burning more calories than you consume. Here are some strategies that can help you burn fat:

Exercise regularly: Cardiovascular exercise, such as running, cycling, or swimming, can help you burn calories and increase your metabolism. Aim for at least 30 minutes of moderate-intensity exercise most days of the week.
Add strength training: Building muscle can help you burn more calories at rest, as muscle tissue requires more energy to maintain than fat tissue. Incorporate strength training exercises, such as weight lifting or bodyweight exercises, into your routine.
Increase physical activity: Look for ways to increase your overall physical activity throughout the day, such as taking the stairs instead of the elevator, parking farther away from your destination, or taking a walk during your lunch break.
Eat a balanced, low-calorie diet: Focus on whole, unprocessed foods like fruits, vegetables, lean proteins, and whole grains. Avoid sugary, high-fat, and processed foods.
Drink plenty of water: Staying hydrated can help you feel fuller and prevent overeating.
Get enough sleep: Lack of sleep can disrupt hormones that regulate appetite and metabolism, leading to weight gain. Aim for 7-8 hours of sleep per night.

Remember that sustainable fat loss takes time and effort. Focus on making healthy lifestyle changes that you can stick to long-term rather than quick-fix solutions.

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