There’s been a lot of talk lately about different fasting diets. Fasting, although it’s been practiced for centuries, is now becoming more mainstream. You may have seen a related article in the Wall Street Journal just few weeks ago.

As with anything that is popular, we sometimes jump to our own conclusions without properly researching the subject. This was definitely us a few years ago on the topic of fasting. As fitness professionals, we were taught, and strongly believed that you should eat several small meals/day; keep your blood sugar steady and keep your metabolism high; if you restrict calories your fat cells would learn to store calories as fat, etc. These were all things we told our clients, and what we practiced ourselves as well, because at the time it made perfect sense based on physiology and science and the information we had. The thought of going more than three hours without food was unheard of in our gym!

The beauty of our field is that it is constantly changing and new research is being done all of the time. What we’ve realized, the more we know, the more we know that we know so little! It’s part of what we love about what we do; we get to learn all of the time, but we also have to be open to change and be willing to put ourselves out there to say, “maybe what we thought before wasn’t quite right.” That’s hard when you are supposed to be the “expert”.

A few years ago, we started really researching this “trend” and became more and more intrigued as there was so much evidence to support fasting for health and longevity. There are different ways to fast, and not a lot of research to claim one is better than the other. People choose how to fast usually based on what is easiest for their lifestyle:

  • Intermittent Fasting:
    • Alternate day fast: Eating normally for 5 days, but two non-consecutive days/week, calories are restricted to less than 500 for woman and 600 for men.
    • Time restricted eating: Eating within a certain window, usually 8-12 hours. For example, stop eating at 7pm, fast until 9am = 14 hour fast with a 10 hour eating window.
  • Fast Mimicking Diet (FMD)/The Prolon Diet: Developed by researcher and Director of The Longevity Institute at USC, Dr. Valter Longo: 5 day fast 2-3x/year. During the 5 days, you eat specific foods, adding up to 770-1100 calories/day to mimic a water-only fast.

Dr. Valter Longo was one of the keynote speakers last month at the A4M Annual World Congress, a medical conference we attended in Las Vegas, for the second year in a row. The goal of A4M is to deliver innovative, cutting-edge scientific education focused on longevity, and prolonging the human lifespan. One of the main topics at this year’s conference was on fasting, with several doctors and researchers touting this as a viable tool for living a longer and healthier life. The research is very compelling and the potential benefits are exciting:

  1. Autophagy: The body’s system of cleaning out dead or damaged cells from the inside; promotes healthier mitochondria, which creates the energy for us to live and thrive.
  2. Lowers inflammation: Inflammation is a major driver of many diseases and health issues.
  3. Stimulates the immune system
  4. Stimulates stem cell production
  5. Increases cognitive function
  6. Improves insulin sensitivity
  7. Resets hormones and circadian rhythms
  8. Gives the gastrointestinal tract a chance to “rest”; helps to improve the gut microbiome
  9. In cancer patients, promotes a good environment for chemotherapy to work more effectively.
  10. Decreases body weight and abdominal fat.

Let us be clear, these are all potential benefits that are still being studied and researched, and much more is needed to draw concrete conclusions. However, the work done so far is very promising. Rather than focusing on disease prevention, this area of science is looking at health and longevity. Fasting has been done for centuries and there is a lot of research as well as anecdotal evidence that shows it could help with many of the chronic health issues we are facing today. If you’d like more information, below are just a few of the researchers we have been following, and some articles that might be of interest:

  • Dr. Rhonda Patrick’s podcast has been one of our favorite resources on fasting. She’s brilliant and has interviewed some of the top researchers on the subject: https://www.foundmyfitness.com/

*Disclaimer: The information in this blog is for informational purposes only. Please always consult your doctor before considering any new diet, supplementation, or other changes to your normal nutrition and exercise routine.