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Intermittent Fasting vs Calorie Restriction

January 28, 2020

Intermittent Fasting, in a nutshell, is when a person cycles between periods of eating and not eating. The two most popular methods are: 

  • 16:8 Diet (you eat during an 8-hour window and fast for the remaining 16 hours)
  • 5:2 Diet (two days out of the week you eat 600 calories or less). 

Intermittent Fasting usually (but not always) results in a calorie deficit.

Traditional calorie restriction is just that - deliberating reducing the number of calories you consume. In order to do this, some people log food. Some people have a cut-off time for eating - so they implement something like a "no food after 7pm" policy. Others remove all sugary drinks. There are countless ways to cut calories, and different methods work for different people.

Mouse in a lab dishWHICH ONE IS BETTER?

There's a lot of research to support the benefits of intermittent fasting. HOWEVER, the majority of this research has been conducted on animals, not humans. MICE, specifically.


The largest study ON HUMANS to date was conducted by the German Cancer Research Center (DKFZ).  Ruth Schübel and her team at DKFZ examined 150 overweight and obese study participants for a FULL YEAR. At the start of the study, the participants were randomly classified into three groups: 

  • The first group of 50 participants followed a conventional calorie restriction diet that reduced daily calorie intake by 20 percent. 
  • The second group of 50 followed 5:2 intermittent fasting plan that also saved 20 percent of calorie intake over the whole week. 
  • The remaining 50 comprised the control group. They followed no specific diet plan but were advised, like all other participants, to eat a well-balanced diet. 

Following the actual dieting phase, the investigators documented the participants' weight and health status for an additional 38 weeks. (Hats off to Schübel and her team for doing such a thorough study).


They found that improvements in health status were THE SAME WITH BOTH conventional calorie restriction and intermittent fasting.

  • Both groups lost body weight and visceral fat and reduced extra fat in the liver.
  • Those who reduced their body weight by only five percent lost about 20 percent of dangerous visceral fat and more than a third of the fat in the liver -- REGARDLESS OF WHICH DIETARY METHOD THEY USED.
  • There were no differences between the two dieting methods in any metabolic values, biomarkers, or gene activities.


Plain and simple, WEIGHT LOSS IMPROVES OVERALL HEALTH. Period. Assuming a well-balanced diet, the dietary method is really up to you. If it’s easier for you to restrict calories two days a week, go that route. If you love data, grab your phone and log your food every day.

In short, do what works for you!



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