Fasting Mimicking Diet

There are many approaches to fasting. This article is going to focus on Fasting Mimicking because it has been extremely well researched, has tremendous research about it’s benefits, is well tolerated by most people, and is easy to implement.

Fasting has been a traditional practice in religious traditions for thousands of years, with a history of spiritual and health benefits. Our hunter-gatherer ancestors frequently fasted in times of food scarcity and ate abundantly when food was available. 

In modern culture, most of us rarely fast and are in a constant “fed” state as food is always available. Although it still shocks me when read the number of people who die from malnutrition or suffer from food insecurity each year on the planet…. more on that another day.

Those of us fortunate enough to think that eating all of the time is one of the pleasures that living in this time provides probably aren’t fully aware of what it means for our health. 

Fasting has gained a lot of attention in recent years for the health and anti-aging benefits it offers. There are many different fasting practices and fasting schedules being studied. These include calorie restriction, intermittent fasting, water fasting and others. 

The fasting mimicking diet is another way to fast, with impressive research behind it, that may be a gentler and easier option for those looking for health benefits, without the discomfort and life disruption associated with other types of fasting. 

Keep reading to learn more about the fasting mimicking diet, including:

  • What is the fasting mimicking diet?
  • Health benefits of mimicked fasting
  • Who is this diet for and who should avoid it? 
  • Tips for implementing a fasting mimicking diet practice

What Is The Fasting Mimicking Diet?  

The fasting mimicking diet is a 5-day mimicked fast where you follow a plant-based and calorie- restricted diet. Daily meals and snacks consist of vegetables, nuts, seeds, olives, fruits, dark chocolate and legumes, along with teas and supplements.

These foods provide around 750-1100 calories per day, or about 40-50 percent of the average daily intake for most people. 

Day one you get the most calories, around 1100, but then it drops to around 750 to 800 calories per day. Protein and carbohydrates are lower in FMD than a typical diet, while the percentage of fat consumed is higher. 

The fasting mimicking diet allows you to eat whole foods, while the body transitions into a fasting state. In this way, it is much easier, and safer, to comply with a mimicked fast than to water fast, for example, where you literally only consume water. 

Typically, the fasting mimicking diet is practiced for five days each month for three to six months and then once per quarter for maintenance, although this is often adjusted to each individual’s needs, goals and schedule. 

The fasting mimicking diet, known as FMD, was developed by Dr. Valter Longo, director of the Longevity Institute at the University of Southern California.

Dr. Longo is a premier researcher in the field of anti-aging who came to understand how cells sense food. Through his research he discovered that when you under feed the body in a certain way, you achieve the physiological benefits of fasting.

While you could craft your own fasting mimicking diet with the nutrition parameters found in the research, Dr. Longo’s company ProLon® provides the five days of food, beverages and supplements that fits the precise criteria to mimic a fast. 

Here is an example day from the ProLon® Fasting Mimicking Diet:

  • Breakfast: A nut bar
  • Lunch: Tomato soup (just add water)
  • Snack: Kale crackers or olives
  • Dinner: Minestrone soup (just add water)
  • Dessert: Dark chocolate crisp bar

Beverages include herbal teas such as mint and hibiscus. Supplements include algal oil, vitamins and minerals from vegetables and a glycerol-based beverage. 

Health Benefits Of Fasting 

To understand the health benefits of fasting, it is first helpful to understand a little bit about the biochemistry of the fed and fasting states in the body. We are in the fed state after a meal when food is being absorbed.

In the fed state blood sugar and insulin rise and the body actively uses the fat, protein and carbohydrates in the meal for fuel, storage and other body projects. This is also the time when cells grow and divide. 

In contrast, the body shifts to a fasting state overnight or when you haven’t eaten in many hours. This is the time when the body relies on stored fuel for energy and glucose and insulin levels return to a lower baseline.

As time in the fasting state continues the body is able to do many projects that aren’t possible in the fed state, including detoxification

In the fasting state autophagy increases, which is the body’s cellular clean-up crew, responsible for removing waste from the cell and repairing damage.

In addition, the body transitions into ketosis (as it would through a ketogenic diet) and becomes more efficient at burning stored fat as fuel. By day five in a fasted state, it’s even possible to generate new stem cells! 

Fasting allows us to tap into these biological processes that we don’t access when we are in a constant fed state. 

Several mechanisms for these benefits have been proposed, including:

  • With lower insulin, mTOR (mammalian target of rapamycin) decreases, turning down the signal for cells to grow and divide. 
  • AMPK (5’ AMP-activated protein kinase) increases signaling for autophagy and cellular repair. 
  • IGF-1 (insulin-like growth factor-1) decreases, which slows the aging process.
  • BDNF (brain-derived neurotropic factor) increases, allowing for increased brain regeneration and plasticity. 

The fasting mimicking diet was tested in mice at first, and then tested in humans with quite impressive results.

In a recent human trial from 2021, women with obesity received either a five-day fasting mimicking diet or their typical diet with a calorie deficit of 500 calories each day as a control. The study found that the women following the fasting mimicking diet improved insulin resistance and appetite regulating hormones.

You might expect fasting to produce weight loss through muscle loss, but in actuality the fasting mimicking diet preserves muscle mass while allowing the body to release fat. This is a huge benefit!

Here are some of the possible benefits of the fasting mimicking diet: 

  • Supports the immune system
  • Improves insulin sensitivity 
  • Reduces oxidative damage
  • Decreases inflammation
  • Improves energy metabolism
  • Balances the microbiome 
  • Improves sleep
  • Improves memory and cognition
  • Increases fat loss
  • Increases autophagy
  • Regenerates stem cells
  • Improves stress response
  • Reduces blood pressure

Given these physiological benefits and high safety of the diet, the fasting mimicking diet has clinical application for the following:

  • Autoimmune diseases
  • Metabolic syndrome and Type 2 Diabetes
  • Cancer
  • Heart disease
  • Neurodegenerative disease, including Parkinson’s and Alzheimer’s
  • Hypertension
  • Longevity 

Who Is The Fasting Mimicking Diet For/Not For?

The fasting mimicking diet is likely safe for people with the diagnoses listed above; however, it’s always good to work with your doctor for monitoring and personalized care through the process.

If you take medication, you may have to work with your doctor to adjust medications during the fast or support your health in other ways. 

The fasting mimicking diet is also for healthy people who want to optimize their healthspan and slow the aging process. 

There are some people who should not fast because of health factors or life stage. These include:

  • Women who are pregnant or lactating
  • Children and adolescents
  • Those with an active infection, such as a cold, flu or COVID-19
  • Those who are underweight, have chronic malnutrition or anorexia 
  • Those dependent upon insulin for diabetes
  • Those recovering from and illness or injury
  • Those with advanced disease such as kidney, liver or heart disease

Tips For Your Fasting Mimicking Diet

When you’ve decided to embark on your first fasting mimicking diet, and have approval from your doctor, here are some things to consider:

1. Use the ProLon meal kit for your fasting mimicking diet. This will make life easier as each meal, snack and beverage throughout the day is packaged and ready to go. All you’ll need to do is add water to some of the meals. When fasting, preparing food or being around a lot of food may be challenging for you, so make it easy on yourself by outsourcing the food prep. 

2. Prepare for your fast by eating a high quality Paleo diet. You’ll have an easier transition to the fasting mimicking diet and experience less discomfort if you are already eating whole foods and not reliant on high sugar and highly processed items. It may also be helpful to wean off of caffeine prior to your fast. 

3. Each fast is different. Even if you are seasoned at fasting protocols, each time you fast you may have a different experience. Feeling low energy and increased hunger are normal reactions, especially in the first couple days of the fast. As the fast goes on, however, many people will experience an increase in energy and clarity while hunger pangs subside. 

4. Time your fast to your schedule. Some people like to start a fast on a weekend or vacation where they are able to take extra time for rest as needed. 

5. Avoid strenuous exercise. Gentle movement such as walking, stretching and foam rolling might feel good to you during a fast, but don’t push it with anything more intense. Wait until after your fast to resume your regular routine. 

6. Practice self-care. Your fast might be a good time to schedule a digital detox, remove yourself from stressful situations and increase meditation, journaling, time in nature and other forms of self-care. While the fasting mimicking diet certainly has many physical benefits, why not harness the mental and spiritual benefits as well?

7. Get support. Do the fasting mimicking diet with a group or plan for regular check-ins with your coach or provider through the process. It’s more fun together and you’ll have support through the hard moments. 

If you’ve been curious about fasting, the fasting mimicking diet is a great place to start. It’s a gentle option where you get the satisfaction of still eating some food, but the cellular and system-wide benefits of a five-day fast.

The fasting mimicking diet is easy, convenient, with a high safety profile and a growing body of research behind it. If you try it, please let us know!

 

References

  1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3946160/ 
  2. https://pubmed.ncbi.nlm.nih.gov/33420673/ 
  3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5862044/
  4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5357144/ 
  5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6816332/