5 Day Fast Mimicking Diet Plan

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Fasting has been a trending topic in health for a while now. It has long been associated with numerous benefits ranging from weight loss to extending lifespan.

If you look up fasting, you will find many different fasting methods, including water fasting and intermittent fasting.

There is a new type of fasting on the scene, and it is known as the Fast Mimicking Diet. This slowly trending fasting method relies on cutting down calories during its set fasting period.

This article will break down the what, how, and why of the Fasting Mimicking Diet trend. If you are interested, you can follow the five-day fast-mimicking diet plan and enjoy all the benefits.

What Is A Fast Mimicking Diet?

Dr. Valter Longo, originally from Italy, is the creator behind the fast mimicking diet or “FMD”. He is a stem cell biologist and biogerontologist who has been researching how fasting impacts aging, diseases, and cellular protection. He holds the view that fasting has a potential role in maintaining a healthy and long lifespan.

The Fasting Mimicking Diet is a part of “The Longevity Diet”, a book written by Dr. Valter Longo. You can check out the entire plan from his book that you can purchase on Amazon or other good book stores.

The fast mimicking diet is put forth as a low-calorie diet plan over a 4 or 5 days, 3 to 4 times a year, that is incorporated in “The Longevity Diet” all year round plan.

Dr. Longo formulated a specific diet that will help improve autophagy within the boy’s cells. This diet stretches across five days.

His idea behind the calorie-restricted diet plan is that one can gain similar benefits associated with water-only fasts, minus the risks.

In essence, it is a way to feed your body the necessary nutrients while tricking it into thinking that it is in fasting mode.

What To Eat On A Fasting Mimicking Diet?

You can eat meals and snacks while keeping the calorie restriction in mind. The calorie intake is designed to give you the best benefits over the stretch of the diet. Typically, this intake is calculated as 1,090 kcal on day one and 725 kcal over the next four days.

The diet aims to feed a person about 34% to 54% of regular calorie intake.

The meals within the fast mimicking diet plan include low-protein and low-sugar foods. However, these are not just random foods.

The diet is formulated to include specific nutrients that will help improve autophagy. The diet is Vegan with lectin-light, nutritious whole foods. 

You can choose to follow this diet once a month, or every three months or two to three times a year, depending on the results you are looking for.

Who Is the Fast Mimicking Diet Designed For?

The fast mimicking diet is well-suited for overweight individuals who wish to shed body fat. It is also designed for those struggling with chronic health problems (post-approval from your qualified Medical Practitioner). Additionally, it is suitable for people who wish to gain from its various benefits and improve their health and lifespan.

However, certain individuals should not follow the fast mimicking diet. This includes children, lactating or pregnant women, people with eating disorders. Always check you don't have a condition that may be aggravated by calorie restriction.

If you intend to follow the fast mimicking diet plan, you must first ensure you are clear to do so. If there are any lingering doubts, we can only emphasis again, get advice from a medical professional before proceeding.

Benefits Of Fast Mimicking Diet

There are some potential benefits that fast mimicking diets offer. These benefits were observed in a small study conducted by Dr. Valter Longo.

Reduced Inflammation:

Studies have indicated following a fasting mimicking diet resulted in reduced inflammation markers, including proinflammatory cytokines. It was also able to suppress autoimmunity and increase levels of corticosterone.

Weight Loss:

In the FMD study conducted by Dr. Longo, it was noted that the participants in the fasting group were able to reduce more belly fat and weight compared to the participants in the control group.

There is evidence backing weight loss associated with calorie-restrictive diets.

Reduced Blood Sugar: 

The same study by Dr. Longo also indicated that participants with high levels of blood sugar experienced lower blood sugar numbers after the fasting period. This indicates that FMD has the potential for a positive impact on diabetes.

The study also observed the regeneration of β-cells (cells in the pancreas that synthesize insulin).

Improved Cognitive Function:

It could also potentially slow down neurodegenerative diseases like Alzheimer's and dementia. Animal studies indicated that fasting increased nerve cell generation and improved brain function.

Improved Cardiovascular Health:

Participants in Dr. Longo’s study also showed improved levels of cholesterol and blood pressure. These participants initially started off with higher levels of both markers.

Delayed Aging:

Dr. Longo’s research was mainly to study the anti-aging process and slow it down. Studies have shown that following short-term calorie-restricted diets lead to enhanced autophagy in mice.

Since autophagy is associated with slowing down the process of aging, FMD could potentially help in increasing the longevity and healthspan of humans.

Improved Cancer Treatment And Prevention:

A certain study has indicated the effectiveness of FMD in improving the efficacy of chemotherapy treatments. The research indicates fasting could help manage some forms of cancers.

Additionally, animal studies have shown it may even help prevent cancer with lower incidences of cancer in the mice.

Water Fasting Rewards:

Water fasting is not for everyone. It comes with a series of potential risks like dehydration, fatigue, electrolyte imbalances, etc. However, a fast-mimicking diet plan can potentially offer you all the benefits of water fasting without the same risks.

These are only considered potential benefits. There is a need to do extensive, long-term human studies to gain conclusive results regarding the advantages of the fast mimicking diet.

A Five Day Fast Mimicking Diet Plan

If you are planning on designing your own fast-mimicking diet plan, you should keep these numbers in mind.

On the first day, you should include 56% fat, 34% carbs, and 10% protein. For the rest of the days, your meals should consist of 47% carbs, 44% fat, and 9% protein.

5 Day Fast Mimicking Diet Plan

You may have black tea and coffee without any sugar or cream.

Here are some ideas for a five-day fast-mimicking diet plan. You will have to adjust the quantities appropriately to match the required calorie intake.

Day One Menu

Day one starts off with extra calories. You can start off your day with a nutty snack bar, no sugar and a cup of tea (also no sugar or creamer). Your lunch may include a soup with some healthy crackers. Alternatively, you can cook a veggie hash.

If you like to snack in between, keep it light. Munch on some olives to keep you till dinner. Your dinner can be another bowl of soup. Alternatively, you can try a bowl of broccoli and lentils.

Remember—whatever meal you decide to incorporate into your diet plan, it should have the appropriate amount of calories and nutrients to qualify as a fast-mimicking diet.

Day Two To Five Menu

The next four days have a further reduced calorie intake. You can incorporate a hummus and a raw veggie platter, some green salad, and soup into your second day. Munch on some olives or baby carrots for a snack.

If you prefer, you can keep the same meal plan for the rest of the days. If you want variation, you can try other things; all while maintaining the right calorie intake.

Soups and breakfast bars packed with nuts are easy meal plans. You can try various soups with kale or seed crackers to liven up the meals.

Additionally, you should also ensure to hydrate properly. Make sure you are drinking adequate amounts of water for optimal hydration each day.

You may also want to take some supplements. However, it is highly recommended you talk to a professional before starting any supplements.

Downsides Of 5 Day Fast Mimicking Diet Plan

While there are lots of advantages to the fast mimicking diet, there are also some potential downsides.


Fasting is not meant for everyone. While the fast mimicking diet seems easier than water fasting, it can be quite taxing for some people. It requires willpower and discipline to adhere to the five-day meal plan.

At the end of the diet plan, some people tend to feel fatigued, whereas others face no problems whatsoever. If you are interested in the diet plan, you should take this factor into consideration. Will this diet plan affect your routine? If yes, then you should consider doing it during a slow week.

Not Suitable For Everyone

As mentioned earlier, this diet program is not recommended for certain groups of people. Anyone who is pregnant, breastfeeding, struggling with eating disorders, and/or malnourished should not attempt to follow this diet.

Additionally, if you are selecting a pre-packaged diet meal kit, you should be wary of the ingredients if you have allergies.


If you are subscribing to a pre-packaged meal kit, then each FMD cycle will be costly for you. These costs will rack up if you want to be consistent with the diet plan.

5 Day Fast Mimicking Diet Plan: The Bottom Line

Healthy individuals may benefit from following the five-day fast mimicking diet plan. FMD banks on self-discipline since it requires you to follow a very specific calorie-restricted diet over a stretch of five days.

part of the 5 Day Fast Mimicking Diet Plan

Research has shed some light on the potential benefits of the fast-mimicking diet. However, you should note that following the plan one time will allow you to reap any benefits. This diet is recommended initially, once every month for every three months.

You can create your own meal plan following the specific rules of FMD if you are well-versed in nutrition and calorie intake.

There are also certain FMD meal plans readily available online. One such meal is the ProLon meal. This is a prepackaged five-day meal kit for those interested in trying the fast mimicking diet.

You should also remember that the Fasting Mimicking Diet is just a small part of a larger more inclusive anti-aging plan created by Dr Longo from his research and in his latest book:
The Longevity Diet, Slow Aging, Fight Disease, Optimize Weight.

However, before you begin any type of fasting, make sure to consult your doctor to get the green light.

Rosemary Richards