Intermittent Fasting / Time-Restricted Eating


Definition: intermittent fasting or time-restricted eating is an umbrella term for diets that cycle between periods of fasting (no eating) and periods of non-fasting (eating)


 It's okay to eat like this...as long as it's early in the day ( image source )

It's okay to eat like this...as long as it's early in the day (image source)

I’ve been experimenting with intermittent fasting for several months now.  

I first heard about it when I was in grad school.  One of my clinical instructors quoted a study that showed the only proven way to prolong life was through fasting.

Recently, I’ve been seeing more and more studies, blogs, and people talking about intermittent fasting.  My friends Seth Oberst and Jeff Ford have both told me about the profound benefits of this “diet”.  So like all health interventions, I thought I’d take a look at the best study out there…an experiment on myself.

At first I was skipping breakfast and only eating from 12pm-8pm.  

This was terrible.  It really threw my system off.  I didn’t feel great.  I didn’t have any energy.  And I gained weight.  

But I was responsible for a big part of this failure.  By the time I got home from work around 5:30 I was starving.  I started eating a ton of pre-dinner snacks as I was cooking dinner.  Then I’d over serve myself for dinner and finish it.  I was essentially eating most of my calories between 5-8pm.

 This was basically how I ate when I came home from work after fasting (image source)

This was basically how I ate when I came home from work after fasting (image source)

Then I read some studies on the circadian cycle and how important it is when it comes to diet and weight loss.  So I started trying to simply cut down the hours of eating per day.  I started to trim the hours back from the latest meal.  I tried to make my last meal earlier in the day.

An 8 hour cycle isn’t socially possible as a physical therapist.  I can’t eat my breakfast eggs while working on someone’s shoulder.  Well, maybe if it was a breakfast burrito, but that wouldn’t be good for business.

So instead I try to eat my last meal before 7pm.  It usually ends up being a 10-11 hour feeding time.  I also try to prepare a shake a couple times a week and skip dinner to cut the feeding time down even more.

With this type of early time-restricted feeding I’ve had a lot more success.  It allows me to reap the benefits without sacrificing my social life or developing orthorexia nervosa.  I feel better, have lost some weight, and have more energy.

And another important benefit…it makes day-drinking much more acceptable!

Some of the General Benefits of Time-Restricted Feeding

  • Weight loss
  • Improved health
  • Decreased morbidity
  • Increased mortality
  • More freedom in our diets

The last benefit is worth pondering.  By using time-restricted feeding as the global focus, it allows for individual variability in the details.  In other words, it doesn’t limit specific foods or cause a purge from prolonged suppression.  It allows people to use whatever diet works for them (paleo, vegetarian, ketogenic, etc.) in a more efficient manner.

Some of the More Specific Benefits

  • Increased human growth hormone
  • Improved insulin sensitivity
  • Better cellular repair
  • Improved gene function
  • Increased metabolic rate
  • Reduced inflammation/inflammatory markers
  • Reduced LDL cholesterol/ blood triglycerides//blood sugar/insulin resistance
  • Increased BDNF
  • Increased rate of nerve cell growth
  • Improved resistance to oxidative stress

Some of the Research

Rhonda Patrick shared a great review of some of the studies on time-restricted eating:

  • Eating within an 11-hour window was associated with a decreased breast cancer risk and reduction in recurrence by as much as 36%.

  • Earlier meal timing associates with improved effectiveness of weight-loss therapy in overweight and obese patients.

  • For each 3-hour increase in nighttime fasting duration was linked to a 20% lower odds of elevated glycated hemoglobin (HbA1C), which is a more long-term marker of blood glucose levels.

  • For each 10% increase in the proportion of calories consumed after 5pm there was a 3% increase in the inflammatory biomarker c-reactive protein otherwise known as CRP.

  • Eating one additional meal during the day (instead of the evening) was associated with an 8% decrease in CRP.

  • Eating within a 12-hour window improved sleep and increased weight loss in normal weight people.

What to Do

We don't have to do a 30-day cleanse, avoid grains, order a full cow, or spend a ton of money on juices.  We just have to limit the hours we eat.

For successful behavior changes to occur we should focus on small actions.  Gain momentum with easy, attainable goals.

It's much better to have some success with the small things rather than failing while trying for a bigger change.

Here are 3 different small strategies to help adopt a time-restricted eating pattern:

  1. Try to eat your last meal an hour earlier
  2. Skip dinner and drink a shake on the way home from work once or twice a week
  3. Eat a bigger breakfast and lunch

Like all changes, it will be a little uncomfortable and take some effort.  But as you've just read, the benefits are worth it.

Summary

Intermittent Fasting/Time-Restricted Eating can prevent heart disease, cancer, obesity, metabolic syndrome, diabetes, and neurodegenerative diseases (alzheimer’s).  

It can not only improve the quality of our lives, but prolong it as well. 

Think about how many lives could be saved, how much quality of life would improve, and how much money our country could conserve if everyone understood and implemented this…


For more information please check out this article