Five Days on ProLon’s “Fasting Mimicking Diet”

Several of you have asked about the ProLon FMD diet I tried, and specifically how I felt during and after. FMD stands for Fasting Mimicking Diet, so it’s not truly a fast. It’s a five day program created by Dr. Valter Longo, director of the Longevity Institute at USC and author of The Longevity Diet. After years of scientific research on the benefits of fasting, he found that certain nutrients in exact quantities trick the body into a fasting state. Longo developed a packaged five-day plan with these ingredients so people could reap the benefits of fasting without hunger or negative side effects. The FMD gives the body the stem cell-based rejuvenation of a five day fast while getting to eat real food.

The main goal of the FMD is cellular renewal by triggering “stem cell-based regeneration and autophagy (the clean up of aging & damaged cells)” which promotes stem cell-based renewal.  While weight loss is also likely when fasting/consuming limited calories, the ingredients in the FMD target vascular fat surrounding the organs while protecting lean body mass. Many report significant slimming in the abdomen area because of this. Enhanced focus and better metabolic health are additional pluses from following the program as well. To learn more about FMD, the website explains the program and scientific support thoroughly, much better than I can here.

So, how did I feel during the FMD 5-Day Fast?

Because I was ready and very motivated after committing to the five days in January, day one wasn’t too difficult. Following the protocol was a novelty so I expected, but never got overwhelmed, with hunger. Caffeine isn’t allowed and I missed my morning almond milk latte which perhaps contributed to the mild headache throughout the day. Day one primes the body to transition to a fasting state. Along with two packaged soups, I ate the provided L-Bars, Kale Crackers, and olives (approximately 1100 calories). Everything was pretty tasty.

On day two, I still felt a bit of excitement around the program and the headache subsided. I felt pretty normal with a few minor hunger pangs that were satiated with the supplied food. Components – soup, L-Bars, etc. – were very similar to day one, and an “L-drink” providing energy and nutritional support, was introduced to the program. I sipped it along with massive amounts of herbal tea throughout the day. The body switches to fat burning mode and autophagy begins. From here on in, the caloric intake is reduced to 750.

Day three was challenging and also the day with the least amount of food. No olives today and they were sorely missed. I love the L-Bar’s but could only have one. I was hungry and drank endless amounts of water, herbal tea and the L-Drink to fool my stomach into thinking it was full. The Kale Crackers were savored with every minuscule bite to maximize the pleasure of crunch. Today the body goes into cellular recycling and ketosis.

By day four, I was very hungry. Looking at the menu ahead with soups and olives, I planned carefully when I would eat them. I could have easily devoured everything by noon, but stretched it out strategically. I was never quite satisfied this entire day. I was cold and had very low energy for the first time in the program.  Knowing there was only one more day ahead kept me determined, but it was an overall tough day. I went to bed hoping desperately I’d feel better in the morning. Autophagy continues and stem cell-based regeneration ramps up.

I woke up thrilled it was nearing the end and proud I’d made it to day five, without any glitches. All the aches from the previous day vanished and I felt great. By far, it was the easiest day with hunger pangs gone. I wasn’t even tempted by the food and smells of the market when I shopped to re-stock the kitchen. Stem cell-based regeneration continues to enhance cellular renewal and the body.

Day six is the transition day and it’s recommended to eat light starting with liquids or soups. I  decided to make Kitchari using the recipe from Pamela Salzman’s book Kitchen Matters. Pamela, who I follow on Instagram/blog, does the FMD several times a year and suggests kitchari as an easy to digest meal when re-introducing food to the diet. Frankly, I wasn’t hungry, but ate a little before heading out for the day. I felt great with energy, a small appetite and a clear mind. I skipped coffee and didn’t miss it at all. Stem cell-based rejuvenation continues for up to 5 days once the FMD is completed return to a regular healthy meal plan.

A week later, I’m feeling great and have returned to normal eating. I’m working on following Dr. Longo’s longevity diet which is predominantly pescatarian/vegan. I’m planning on repeating the FMD again within the next couple of months and then use it as a metabolic maintenance program once or twice a year.

Things I’d suggest if you do the FMD:

1. Ween off caffeine several days before the start
2. Clear your social calendar for 5-6 days
3. Keep a light workload and count on down time
4. Have something ready to eat for transition day 6
5. No strenuous exercise

I’m planning on repeating the FMD again within the next couple of months and then use it as a metabolic maintenance program once or twice a year.

More information on the program is available here.

The information and opinions expressed are my own. I am not a healthcare professional and you should always consult your physician, doctor, or healthcare provider before beginning any weight loss, nutrition or exercise program.

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