Alternate Day Fasting

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Alternate day fasting means that you fast one day and then the next day you eat whatever you want, a feast day. So, a given week may contain 3 fast  days and 4 feast days  next will have 4 fast days and three feast days. By alternately fasting and feasting one can restrict their caloric intake over time.  If you take in fewer calories than you expend by exercise you lose weight.  If you are overweight, this will improve your health. The fasting can consist of either a total fast where you consume only fluids like water that have no caloric value or a very low calorie meal of less than 500 calories.  The effects are supposed to be very similar.

I certainly want to do both f those things.  I am 6’1” tall and 50 years old. When I started on 8/5/2017, I was overweight at 218 lbs with a BMI of 28.8.(according to the NIH)  My goal weight is 189 for a BMI of 24.9 which is at the very high end of normal.

The last time I had a normal BMI was back in 1993.  I had been out of college for three years and was young and single in San Francisco.  Since then, my weight has gradually crept up.  Although I have been generally active and exercise 5 days a week, nothing that I have done in the intervening 27 years has led to a continuous period at my goal weight. Yesterday, I turned 50.  As you get older, a number of things that just mildly bothered you become constant nagging issues.  One thing is my knees.  I did a trail run last year in December and through the process of 5 practice run and one race on the trail I managed to permanently damage my knees. I feel pain whenever I walk down stairs or run and my knees make a loud crunching sound whenever I go down stairs. I’m doing strength exercises to help take the pressure off of my knees.  I fear this is not going to be enough to regain my ability to run. My hope is that by reducing my weight by 30 pounds, I will make running a lot less painful.

Before I started alternate day fasting, I had a physical exam from my doctor.  Although generally in good health, there were a couple of test results which were troublesome.  My fasting glucose was higher than the normal range and my liver enzymes were also out of normal. Both of these are probably related to my being chronically overweight.  I hope that by reducing my weight I will be able to bring both of these health indicators back into the normal range.

What is an alternate day fast?

You can get an overview of alternate day fasting from the every other day diet website.  The author, Krista Varady, Ph.D has been researching alternate day fasting awhile and has authored a book about it. You may not need to buy a book about it. Basically, you eat one day, you fast the next and so on.  You can sum up the concept in one sentence. Reviews on Amazon seems to say as much.

Another doctor Jason Fung, MD. Is also a huge proponent and has written his own book.  Apparently this book is a bit meatier on the science of why and how intermittent fasting can improve your body function.  I’m going to read this one at some point.

Why An alternate day fast?

I have had some success in restricting my calories and watching my macronutrients before.  It has proven very hard for me. It is only by exercising a great deal, that I was able to moderate my eating enough to be in caloric deficit.  The core of my exercise consisted of commuting to work by bicycle. This was a round-trip totalling 15 miles over some significant hills.  When I stopped commuting because of a job change, my weight went up quickly.  In addition to needing a lot of exercise, restricting calories daily took an enormous amount of mental attention.  I had to keep a journal of everything I ate.  I had to watch for when I was approaching my daily calorie limits. Automation like myfitnesspal made the logging somewhat easier.  Constantly directing my attention to exactly what and how much I was eating was a burden.  Plus, it didn’t work.  I would make some progress, but it was unsustainable. I have never been able to get back into the normal BMI range or get my weight below 200 lbs. for more than a month over the last 30 years.

Alternate day fasting suggest something different.  I only have to pay attention to my eating on fast days.  The feast days are care-free.

Week One update.

I have completed my first week of alternate day fasting and these are my results:

I lost 4.6 lbs. This seems like a lot and can’t possibly all be body mass. Some of the loss has to be water and the absence of digesting food.  Although on fast days I certainly ate a lot of salty food and religiously drank water.  Time will tell.  My caloric intake on those days was as follows:

The first day of fasting I miscalculated how much food I was eating so I went over 500 calories.  ( I ate two stoned wheat crackers instead of the one I should have).

The first two fast days were difficult.  I have been conditioned for decades to eat several times a day. I am currently working from home as well so I am right next to the refrigerator. I have in the past eaten out of boredom and those habits were in full effect the first two days.  Breaking the fast the second day, I ate more than usual. On the fourth day, a feast day, I had lunch meetings downtown at a restaurant at noon.  Later, my friends took me out for a three course meal downtown along with cocktails and wine, so I ate more than my usual of that rich and caloric food. In fact, I exercised a bit of restraint because I knew that I would likely be overcompensating for the fast days. The third fast day was easier, and today, the last fast day I decided I wasn’t going to eat anything and see if that had any effect on how I felt or the weight.  I ended up eating some tuna because I got too hungry.

Overall, I am pretty happy with the experience and the results.   Although fasting is not fun, it isn’t an incapacitating experience either. I am fairly optimistic that I can maintain this pattern for at least 4 weeks.