Photo by Oladimeji Ajegbile

Are you eating your main meal after 6 pm? You should read this.

There are three types of intermittent fasting: whole-day fasting, alternate-day fasting, and time-restricted eating.  These types of diets are not calorie restricted.  In other words, you are not counting calories or eliminating certain foods from your diet.  These are “eating plans” and not diets so if you are considering one, understand this is not a weight-loss scheme and that is a good thing! 

Collectively, these eating plans are based on a natural biological process called the circadian rhythm.  Animals fall into one of two types of circadian rhythms – nocturnal and diurnal.  Coyote are nocturnal which means they sleep during the day and are active at night.  Humans are diurnal which means they sleep during the night and are active during the day.  The theory is that humans who are not following their natural diurnal rhythm gain more body fat and have higher rates of chronic disease.  These eating plans take advantage of our natural diurnal biological clocks.

There is good research that shows these diets decrease insulin and improve insulin sensitivity, lower blood pressure, cholesterol, oxidative stress and body fat.  Intermittent fasting does produce a reduction in food intake, so they all reduce calorie intake – but it is not as noticeable as when you restrict your calories at meals.   These diets, when adhered to over a few weeks, also appear to lessen hunger.  

The 3 types are:

  1. Whole day fasting which involves eating no more than 500 calories 2x per week.  The 500 calories is just enough to prevent muscle atrophy and help the body release its fat stores to provide energy.  On the other days you eat whatever you whatever and whenever you want. 
  2. Alternate day fasting involves eating no more than 500 calories every other day and eating normally on alternative days. 
  3. Intermittent fasting restricts eating to a certain time period – anywhere from 4 to 8 hours window like 8 to 4 or 10 to 6 PM.  Eating early in the day aligns with human’s natural circadian rhythms in metabolism.  Intermittent fasting is similar to the way people used to eat – 8 am breakfast, 12 noon lunch, and dinner by 6 pm – roughly 10 hours with no snacking – so this isn’t a new concept.  Most people report doing best on this type of intermittent fasting because there is no calorie restrictive days. 

Personally, I think the idea is to stop the incessant snacking between meals, stop eating after 6 pm, and get to bed before the hunger monster attacks around 11 PM!