Video | The Study | Reasons Fasting Works | Improve Results | Takeaway

Is your plan for weight loss and better health failing to get off the ground? Are you tired of counting calories? Then, consider counting time instead. 

A 6-month study published in JAMA found that intermittent fasting was more effective for weight loss than calorie restriction, and participants assigned to the fasting group had an easier time sticking with the program. This blog post shares the simple strategy the study participants followed so you can do the same. 

Stop Counting Calories, Count Hours Instead! [Video]

In this video, you’ll learn…

• The results of the six-month study testing fasting vs. calorie restriction.
• Three reasons why fasting works.
• Three way to improve your results.

The Study

I am a proponent of intermittent fasting and wrote a book on fasting a few years back.

It is always nice to see new research comparing fasting to other methods of health and weight control that cover a period of time. 

A study published on Jama Network Open was conducted for six months, so there was time to show results and evaluate how easy or hard it was for participants to stick with the eating change. 

The study included 75 participants with obesity and type 2 diabetes. They were split into three groups. One group followed a daily fasting routine, one restricted their daily calorie intake, and the other group acted as a control group.

The fasting group could eat anything they wanted but compressed their food intake into an 8-hour eating window between the hours of noon and 8 PM. The second group reduced their daily calorie intake by 25%. And the control group did not change their diet at all (1).

The Study Results

After six months, participants in the fasting group experienced greater weight loss and compliance with the program compared to the calorie restriction group. 

Specifically, the fasting participants lost 3.56% of their body weight compared to the controls. That means a 200-pound person would lose about 7 pounds over six months. I am sure that result underwhelms some of you. I will share ways to boost the result in a moment. 

However, keep in mind that the participants didn’t change their food choices. They only compressed their eating window to 8 hours to get that result. Before we look at weight loss boosters that you can add, let’s take a moment to appreciate why this worked. 

Reasons Fasting Works 

#1: Natural Calorie Restriction

The study authors noted that “Participants in the [time-restricted eating] TRE group found it easier to adhere to their intervention and achieved greater overall energy restriction compared with the [calorie restriction] CR group.”

To state that plainly, the fasting participants, who could self-select foods and eat freely during 8 hours of their day, ended up restricting their calories more than the participants who put calorie restriction as their top goal. 

The takeaway here is that fasting leads to natural calorie restriction. 

The fasting participants naturally, without specific intent, reduced their daily energy intake by 313 calories. The calorie restriction group averaged a reduction of 197 calories per day. 

A possible explanation for this is that it is easier to count hours than to count calories, making the fasting participants more consistent in their efforts. 

#2: Metabolism Boost

Fasting can also support your metabolism. When you fast, your body has the time and rest it needs to create chemical and hormonal advantages that boost metabolism.

Your metabolism is the sum total of all the chemical processes going on inside your body. Certain regulators of metabolism, such as norepinephrine and growth hormone (GH), are increased through fasting (2) (3).

#3: Sync Your Circadian Rhythm

Not only does fasting help your body keep metabolically important hormones high, but it also allows you to work with your body’s natural metabolic rhythm. 

When you are intermittently fasting, and your eating window is open, you will be consuming calories (aka energy) at a time when your body is best equipped to handle them. The human body is designed to be active during daylight hours and to sleep at night. We refer to this daily cycle as your circadian rhythm. 

By shortening the number of hours during which you consume food, you work with your body’s natural rhythm and become a more efficient metabolic machine. During your fasting period, you give your digestive system a rest, which resets the hormones that impact your weight.

How to Improve Results 

As I mentioned, fasting participants lost an average of 3.56% of their body weight over the six-month study period. Are there ways to improve your results with fasting? Yes. 

Eat a Low-Carb Diet

If there is one culprit that we can point our finger at in the upward trend of obesity, it’s the overloading of refined carbohydrates in our diet.

A low-carb diet is an effective way to stabilize your blood sugar and insulin levels and control hunger. This combination makes it easier to fast and creates an internal state that favors fat loss.

If you need somewhere to start, view my blog post “3-Day Eating Plan to Start or Restart Low Carb Dieting.” It will get you up and running quickly. 

Stop Eating 3 Hours Before Bed

The study participants finished eating for the day at 8 PM. For those of us who are early risers, 8 o’clock comes close to bedtime. 

In the evening hours, your circadian clock influences the production of hormones that prepare you for sleep. Eating too close to bedtime can work against this hormonal shift, keeping your blood sugar and insulin elevated and blocking fat burning overnight. To encourage fat loss, stop eating a minimum of 3 hours before bed.

Shorten Your Eating Window

Everyone’s metabolism is different. The study participants followed a 16:8 fasting schedule, meaning they consumed all of their calories within an 8-hour period and fasted the remaining 16 hours of the day. You may be able to boost your results by reducing your eating window by one to four hours. In other words, consume all your calories within a four- to seven-hour eating window daily.

But keep in mind that the participants fasted daily for six months. While the hours you fast can vary a bit from day to day, commit to fasting daily for the best results.

Takeaway

At the start of the post, I promised to share the simple strategy the study participants followed so you can do the same. Let me recap the instructions that the participants in the fasting group received. 

Those in the fasting group ate whatever they wanted between noon and 8 PM. That also means they fasted from 8 PM to noon the following day. 

During the 8-hour eating window, participants were not required to monitor their calorie intake. During the 16-hour fasting period, participants were encouraged to drink water and permitted to consume non-caloric drinks, so they did not put cream in their morning coffee.

For that degree of effort, they lost an average of 7 pounds in six months [based on a 200 lb. person]. If that pace works for you, then great. If you want to encourage your body to lose faster, combine the daily 16:8 fast with a low-carb diet and stop eating three hours before bed, which may require you to shorten your eating window or shift it to earlier in the day.

Thank you for reading and have a wonderful week!

References:

(1) Pavlou, Vasiliki, et al. “Effect of time-restricted eating on weight loss in adults with type 2 diabetes: a randomized clinical trial.” JAMA network open 6.10 (2023): e2339337-e2339337.

(2) Zauner, Christian, et al. “Resting energy expenditure in short-term starvation is increased as a result of an increase in serum norepinephrine.” The American journal of clinical nutrition 71.6 (2000): 1511-1515.

(3) Ho, Klan Y., et al. “Fasting enhances growth hormone secretion and amplifies the complex rhythms of growth hormone secretion in man.” The Journal of clinical investigation 81.4 (1988): 968-975.

About the Author

Becky Gillaspy, DC, is the author of The Intermittent Fasting Guide and Cookbook and Zero Sugar / One Month. She graduated Summa Cum Laude with research honors from Palmer College of Chiropractic in 1991.