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If you want to gain all the benefits of fasting while still eating food, then you should seriously consider the ProLon Fasting Mimicking Diet (FMD), which was created by Prof. Valter D. Longo. This exciting revolutionary program is a 5-day diet that mimics a fast but includes certain foods that promote the same benefits as fasting.
FMD is a plant-based, whole foods diet that provides macro and micronutrients in precise quantities and combinations that nourish you while being able to “fast” without the hunger.
There are several well documented benefits to fasting, but most people cannot do a water only fast since it is mentally and physically challenging not to eat food for several days in a row. Since starving can cause low energy and sleepiness, making it difficult to function, the FMD helps mitigate these negative effects by including specific nutrients.
The Fasting Mimicking Diet contains between 750-1150 calories per day and consists of proprietary energy bars, snacks, vegetable-based soups, beverages, and supplements that are purchased through ProLon. It’s a low carbohydrate and low protein diet with healthy fats consisting of MCT oil, nuts, and olives.
The Cost of the Diet…and of Not Doing the Diet!
ProLon provide five days-worth of food so you don’t have to shop or plan out your diet. The cost is reasonable if you consider it’s almost a week’s worth of food, and you won’t be eating out or buying any other food during those five days.
When using the FMD, you are also supporting a great non-profit organization. ProLon gives back 60% of their profits to the non-profit Create Cures, which was founded by Prof. Longo. Create Cures has a mission to promote projects aimed at identifying integrative low-cost therapies for the prevention and treatment of major diseases such as Alzheimer’s Disease, cardiovascular disease, Multiple Sclerosis, Crohn’s Disease, and diabetes. This may benefit us all one day!
The Fasting Mimicking Diet has now been tested independently in over 32 human trials conducted in 18 different university research centers. These studies show how beneficial this scientifically designed “fast” is and how it can benefit you and your health. Considering the reasonable cost and all that you have to gain from the added health improvements, the FMD is definitely a worthwhile investment for people struggling with chronic illness (and the high cost of medications and doctor visits).
Benefits of Fasting
- Help maintain healthy levels of fasting blood glucose, cholesterol, and blood pressure, as well as C-reactive protein, triglycerides, and stem cells
- Reduce excess fat while maintaining lean body mass
- Trim your waistline with focused weight loss from visceral fat in the abdomen
- Promote stem cell-based rejuvenation and renewal
- Trigger apoptosis and autophagy in your body for clean-up of old and damaged tissue
- Gain focus and mental clarity
- Enjoy softer, smoother skin
- Improved energy
- Optimize health span using nutrition – live a longer healthier life!
The Biochemistry Behind the Fasting Mimicking Diet

This isn’t a diet that you can replicate yourself, at least yet. The foods that are included in the Fasting Mimicking Diet were scientifically formulated based on decades of research and selected specifically to mimic the effects of a five-day water fast. These foods do not trigger cellular nutrition sensing pathways but will provide optimal nourishment during the 5-day diet.
Regular diets activate key pro-aging pathways like growth hormone, insulin, and insulin like growth factor 1 (IGF-1). These hormone-signaling pathways sense that you have consumed adequate amounts of carbohydrates and proteins, which causes the body to activate genes that accelerate certain growth pathways. Subsequently these pathways block regeneration/rejuvenation as well as speed up the aging process.
The FMD foods allow your body to trigger protective measures which the body developed over a long period of time as part of natural selection during periods of food scarcity. This switches the body to thrive under these conditions by optimizing its performance through cell rejuvenation. It’s amazing how we can hack into these ancient protective mechanisms in our modern day lives to experience the benefits of fasting!
The clinically tested Fasting Mimicking technology not only promotes autophagy (cellular house cleaning) but also promotes similar stem cell regeneration as would a 5-day water fast, but with FMD you can EAT REAL FOOD. Stem-cell based rejuvenation will continue up to 2-3 days after you complete the ProLon Fasting Mimicking Diet. In individuals who already have high markers, this leads to long-term reduction in IGF-1, glucose, and markers of aging and inflammation. In other words, if you do not need help in this area, no significant changes will occur with those markers when going on FMD, and it won’t be harmful. You may still experience weight loss and other benefits of fasting.
The Fasting Mimicking Diet is recommended for those who:
- Are already healthy but want to optimize health and wellness
- Want the benefits of fasting, without the starvation and hangry feeling
- Are concerned with age-related diseases or want to fight the effects of aging
- Are looking for visible loss of abdominal fat
- Have elevated health markers for chronic conditions
- Have cancer (medical supervision is recommended)
Transitioning Back to a Regular Diet
Transitioning back to your regular diet is easy, and you can maintain many of the fasting-related benefits. For the first day after the diet, it’s best to start back slowly with soups, juices, smoothies, and very light meals. Most importantly, do not binge during this time. Take it slow. This is a great time to ditch the soft drinks and processed foods if you were partaking in those prior to the FMD. These foods may not agree with you right after the diet, and hopefully you have lost your taste for these types of food and drink.
After a one-day transition, you can return to your normal diet. Pay attention to your actual hunger cues and try not to overeat. You’ve gone through a reset of sorts, so take advantage of this opportunity to change some habits. Try to preserve your benefits of fasting by taking a new healthy approach to eating.
Promising Pre-Clinical Studies Using the Fasting Mimicking Diet
Researchers are currently studying those undergoing chemotherapy, and if the FMD enhances the antitumor activity of cytotoxic chemotherapy, while protecting healthy cells. In animal studies, FMD was as effective as fasting in sensitizing tumors to chemotherapy. The results of the human trials should hopefully be released soon and according to Dr. Longo in an interview I heard recently, the results are very promising.
Animal studies demonstrated that the use of periodic cycles of FMD caused β-cell regeneration in the pancreas which restores insulin generation in islets, reversing type 1 diabetes and type 2 diabetes in mouse models.
Studies in mice also showed that the Fasting Mimicking Diet is effective in ameliorating demyelination and symptoms in a Multiple Sclerosis (MS) mouse model.
I’m very curious to see the results of clinical studies in these areas. I will be updating this blog article when the results are released.
Cautions
Trying to replicate these results doing your own water fast or DIY Fasting Mimicking Diet can be dangerous. If interested in trying water fasting, please do your own research and see a qualified health professional. For the FMD, if you have any health conditions or are on medication, you should seek approval and supervision from a healthcare professional. ProLon requires you to fill out a brief questionnaire when signing up. Please be honest about your health conditions and medications for your own safety.
Those who should not participate in the FMD are:
- Children under 18 years of age
- Pregnant or nursing women
- Individuals who are allergic to nuts, celeriac/celery, oats, sesame (see nutrition statement for complete contents)
- Underweight individuals
- Individuals diagnosed with a serious medical condition or disease, unless approved by an appropriate healthcare provider
- Individuals who, in the opinion of a healthcare provider should not fast or using fasting products for fasting purposes
- Individuals with a known, suspected, or diagnosed eating disorder, unless otherwise determined by an appropriate healthcare provider
- Individuals with a history of cancer, diabetes type 1 or 2, congestive heart failure, or syncope (fainting) unless approved by an appropriate healthcare professional.
- Individuals who have special dietary needs that are incompatible with the ProLon® meal plan
- Individuals over the age of 70 unless approved by an appropriate healthcare provider.
What to Expect During the Diet

You may experience hunger during the diet, but this generally subsides by day 3 or 4. While heavy exercise is not recommended, Dr. Longo says walking is acceptable as long as you have enough energy. You can download the ProLon phone app to help you throughout the diet.
Those who have used the Fasting Mimicking Diet have reported increased energy, rapid fat loss, decreased abdominal fat, improvement of metabolic markers, and softer healthier skin – all the benefits of fasting while eating real food!
As a nutritionist, I always like to tell clients to focus on primary food which is anything that satisfies us but is non-edible, like learning, reading, sleep, joy, adventure, affection, helping others, laughter, pets, satisfying jobs, sex, and friendships. This is different for everyone, so take this time to hone in on your primary foods.
On-Going Maintenance to Preserve the Benefits of Fasting
The recommendation is to repeat the 5-day fasting /25-day refeeding cycle for three to four times in a row for the maximum benefit. For healthy or low risk individuals, the recommendation is to repeat the diet 2-4 times per year. For high-risk individuals, the recommendation is to repeat the diet 3-12 times per year, depending on your health conditions.
Dr. Longo recommends the Longevity Diet for an every-day diet after FMD. I’ve read Dr. Longo’s book, The Longevity Diet, which ultimately led me to do more research on the FMD. This diet is basically a pescatarian diet, with elements of a traditional Mediterranean diet including ancestral foods. The Longevity Diet is predominately plant-based but includes fish 2-3 times per week for the omega-3 and B12 content. Protein content should not be excessive, as seen with the Standard American Diet. As with most healthy eating plans, saturated fats and sugar are greatly minimized.
If you are overweight, Dr. Longo recommends only 2 meals per day and a light snack, and he also supports a 12-hour eating window. If you are interested in learning more about eating for longevity, I encourage you to read The Longevity Diet book written by Valter Longo, PhD.
Ready to try FMD and gain all the benefits of fasting while eating delicious food?
If you would like to experience the benefits of fasting without depriving yourself of food, I highly recommend the Fasting Mimicking Diet. Finally, there is a way to make fasting more enjoyable!
To get started, you can purchase the single ProLon Box which includes 5 days worth of plant-based soups, bars, drinks, snacks, teas, and supplement formula tablets.
If you are ready to make a serious commitment to improving metabolic health and cellular rejuvenation, you can order the Prolon Professional Four-box Bundle which includes four complete rounds which also is more economical per box.
You can view special pricing and purchase any of the Prolon products mentioned above using my provider link for ProlonLife.
I would love to hear about your personal experiences with the Fasting Mimicking Diet and if you experienced the health benefits of fasting over time.
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Medical Disclaimer
The above statements have not been evaluated by the Food and Drug Administration. The products mentioned are not intended to diagnose, treat, cure or prevent any disease. Check with your doctor or nutritionist before starting a new supplement program.
The Functional Nutritionist maintains this website for education, information, and communication purposes. Nothing on this website should be construed as a solicitation or promotion for any products, or for the use of any product in a particular way that goes against the laws and regulations of the country where the user is located.
Sources
Wei M, Brandhorst S, Shelehchi M et al. Fasting-mimicking diet and markers/risk factors for aging, diabetes, cancer, and cardiovascular disease. Sci Transl Med. 2017;9(377):eaai8700. doi:10.1126/scitranslmed.aai8700.
Cheng C, Villani V, Buono R et al. Fasting-Mimicking Diet Promotes Ngn3-Driven β-Cell Regeneration to Reverse Diabetes. Cell. 2017;168(5):775-788.e12. doi:10.1016/j.cell.2017.01.040.
Safety, Feasibility and Metabolic Effects of the Fasting Mimicking Diet (FMD) in Cancer Patients – Full Text View – ClinicalTrials.gov. Clinicaltrialsgov. 2018. Available at: https://clinicaltrials.gov/ct2/show/NCT03340935. Accessed July 1, 2018.
Choi IY, Piccio L, Childress P, et al. Diet mimicking fasting promotes regeneration and reduces autoimmunity and multiple sclerosis symptoms. Cell reports. 2016;15(10):2136-2146. doi:10.1016/j.celrep.2016.05.009.
Di Biase S, Lee C, Brandhorst S, et al. Fasting mimicking diet reduces HO-1 to promote T cell-mediated tumor cytotoxicity. Cancer cell. 2016;30(1):136-146. doi:10.1016/j.ccell.2016.06.005.
