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Last month I have received several requests on how to start an “Intermittent Fast Diet” (IF) of which I found to be thought-provoking as I mindfully went into flashback mode with the mention of “Fast”.  I can vividly remember actually “Fasting” (abstaining from food and liquids) for 24-hours as part of an annual religious observance.  I do not know the effect it had on my siblings, however at the end of the “Fast” I could barely walk to the table to “break the Fast”.

The act of “Fasting” has been around for generations, however the idea of using it as a popular form of weight loss started only 6 years ago by a BBC journalist Dr. Michael Mosley.  When we consider the Intermittent Fast it is just a term for a group of diets or eating patterns that cycle between a period of “Fasting” and non-fasting over a defined period.  The two most popular forms of (IF) is (a.) Whole-day Fast and (b.) Time restricted Feeding.

Whole- Day fasting is a 24-hour period of abstaining from food followed by a 24-hour of eating (Eat-Stop-Eat) pattern.  This is the strictest form of (IF) and not widely used or recommended.  There are variations to the Whole Day Fast such as the “5:2 Diet”.  The diet is easier to follow and designed to allow you to follow your normal meal patterns for five days per week and the other two days you are restricted to eat only 500-600 calories, these are considered your “Fast Days” thus we get the term 5:2 Diet.

Time restricted Feeding (TRF) is the most popular and widely used form of the IF.  This variation involves eating only during a certain number of hours each day.  The most widely used form of the TRF is call the 16/8 Method.  This fasting pattern allows you to fast for 16 hours each day and only eat during the remaining 8 hours on the same time schedule every day.  So, how does this work?  Each day eat your last meal at 8:00 p.m., the next morning “Skip Breakfast” do not eat anything until 12 noon, notice from 8:00 p.m. to 12 noon = 16 hours fast. Now from 12 noon to 8:00 p.m. you can resume your normal meal pattern this is your 8 – hour eating window, thus we get the term 16/8 method.

Research performed on “fat rats” have shown IF improved weight lost, blood pressure, cholesterol and blood sugars, however these results are limited to animal studies.  Human studies have shown that (IF) is safe and effective, however, no more effective than any other diets offering calorie restrictions as noted in a 2017 study found in JAMA Internal Medicine.  The study also reported that the dropout rate was higher among the (IF) group.  Fasting can be difficult,  some of the side effects are weakness and hunger, headaches, fainting, and dehydration.  It is not recommended for people with diabetes, a history of eating disorders like anorexia and bulimia, and if pregnant or breastfeeding.

As a clinician I recommend choosing a diet plan for which you will be able to follow throughout your life, making sound Life Style Modifications to improve overall health.  Consider a study conducted by the U.S. News and World’s Report in 2017, the study evaluated and ranked 40 diets.  For the diet to be top rated it had to be safe, easy to follow, nutritious, effective for weight loss, and effective in preventing diabetes and heart disease.  Study results indicated that the DASH Diet and Mediterranean Diet tied for first place.  Take caution, the Keto diet and the Dukan diet tied for last place.

If you are considering Intermittent fasting, consult your health care provider. Keep in mind it is always best to limit the hours of the day when you eat, make it early in the day between 7:00 a.m. to 3:00 p.m., or 10:00 a.m. to 6:00 p.m., do not eat in the evening before bed time.  Avoid snacking or eating at nighttime and consider following the Mediterranean or DASH Diet during your non-fasting meal hours as you- Hashtag that Intermittent Fast.