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All You Need to Know About Fasting

(Meal Plan)

What is fasting?

Fasting is the ancient voluntary withholding of food for spiritual, health, or other reasons. It has been used for thousands of years by virtually every culture and major religion in the world.


What happens when fasting?

Fasting results in our body using its energy stores; first stored carbohydrates and then ultimately, stored fat.


Why would anyone fast for health reasons?

Abstaining from food for controlled, intermittent periods of time is taking advantage of this metabolic mechanism for an intentional benefit. It is well established that losing excess body weight in the form of fat, especially around the abdominal area (a.k.a visceral fat), is associated with a significantly lower risk of chronic diseases linked to the metabolic syndrome.


How does someone fast intermittently?

There are different types of intermittent fasting methods. A good start is the 16:8 method, which is fasting for 16 hours (includes sleep) and resuming meals for the remaining 8 hours. This could mean you sleep from 12:00 am - 8:00 am, then have your first meal at noon. The 16:8 method can be done on weekends only, weekdays only, or every day. An individual can progress to more intensive fasting methods over time, such as fasting for an entire 24 - 36 hours each week or for 2 days every week. 


Although an intensive fast is more effective for change within the body, it may not always be the best option or even necessary. Everyone has different comfort levels, barriers, and stress levels that may interfere with the process. Hastily fasting without preparation and guidance can result in an unpleasant and unsuccessful experience. Set yourself up for success. For support and guidance please contact Dr. Jason Fung's and Megan Ramos’ clinic.


How long does someone fast intermittently?

Intermittent fasting for health reasons is a temporary intensive dietary intervention. Fasting may be required for a few weeks or up to several months - every person is different. However, after the intervention is over, fasting on a less intensive scale can be a regular part of your life. It can be done every day, every week or every month. 


 What are the potential risks?

If you have type 1 diabetes, have a medical history of diabetic ketoacidosis, have congestive heart failure, are on dialysis or are experiencing kidney failure you should not fast. It is dangerous and highly discouraged. 

Another risk is constipation, but this can be managed with dietary changes.


How do I prepare to fast?

The Pre-Fasting Protocol below (1) minimizes any shock you may experience during a fast (i.e headaches, hunger pangs) because it will ease you into a more restrictive eating pattern, and (2) maximizes the effectiveness of the fast because this protocol will give your body time to use its stored carbohydrates before the fast. That way, as you begin your fast, stored carbohydrates will be depleted and your body will begin to use its stored fat.

To prepare your body, eat a diet high in fat, low in carbohydrate, and adequate in protein (aka ketogenic diet) for 3-7 days. Then begin a stricter high-fat diet for 3 days.


If you have any of the conditions below, please use CAUTION when following a low carbohydrate diet:

If you have type 2 diabetes:

  • and use insulin, you will need to test your blood sugar frequently and adjust the insulin significantly (may need lower by 30-50%). Taking too much insulin when you are eating little carbohydrates will bring your blood glucose to extremely low levels and you may experience ketoacidosis - a life-threatening condition. You must get your doctor to help you adjust your insulin properly before fasting. 
  • and use metformin ONLY - there is no risk.


If you have type 1 diabetes:

  • a low carbohydrate diet is dangerous and not recommended. Instead, a moderate carbohydrate diet is recommended (approximately 50 g/day), so you avoid getting too close to ketoacidosis (blood ketones >1.5 mmol/L).


If you have high blood pressure:

  • and use medication to control it, you will need to adjust the dosages carefully. Taking too much blood pressure medication when you are on a low carbohydrate diet will make you feel very weak, dizzy and you may faint. You must get your doctor to help you adjust your medication properly before fasting.


If you are breastfeeding:

  • you require more carbohydrates than the average person. A low carbohydrate diet is dangerous and not recommended. Instead, a moderate carbohydrate diet is recommended (approximately 50 g/day), so you avoid getting too close to ketoacidosis.
  • Alternatively, you can wait till you are done breastfeeding to start a low carbohydrate diet safely.


The following guidelines are from Dr. Jason Fung's Intensive Dietary Management Program (IDMP) in Toronto.

Pre-Fasting Protocol

For 3-7 days, refrain from:

  • All sweeteners, natural or artificial, including stevia
  • All starchy vegetables, including potatoes/potato starch, yams, beets, turnips, parsnips, and corn.
  • All grains (including quinoa and all types of rice) and products containing flours made from those grains made from grains (almond and coconut flours are okay to consume)
  • All fruits except for avocados, olives, tomatoes, cucumbers and bell peppers
  • Refined sugar: all candies, pastries, chocolates (85%+ cocoa is okay to consume)
  • Soda, diet soda and all juices, even no sugar added juices

  • All alcoholic beverages including dry wine


Then for 3 days, eat only the following:

Food Amount
Eggs unlimited
Bacon unlimited
Salmon unlimited
Sardines  unlimited

Olive oil, coconut oil, MCT oil, avocado oil, macadamia oil

Butter unlimited
Ghee unlimited
Avocado unlimited
Olives unlimited
Bone Broth unlimited
Leafy Greens unlimited
Tea unlimited
Coffee 3-6 cups
All Herbs and Spices unlimited



  • Eat when hungry until satisfied as often as necessary

  • No dairy or nuts

  • You may use up to 3 tbsp of heavy cream for your tea or coffee

We've created a meal plan following this exact protocol to get you ready!


Intermittent fasting in combination with a high-fat, low-carbohydrate diet can be an intensive nutrition therapy for the purpose of losing excess fat and normalizing the body's metabolic processes by instilling more balance.


Studies show beneficial effects of the ketogenic diet relevant to metabolic health, cardiovascular health and gastrointestinal health, such as weight loss (Bazzano, et al., 2014; Shai, et al., 2008), lowering insulin resistance by lowering insulin levels (Noakes, et al., 2006; Hernandez, et al., 2010; Samaha, et al., 2003; Volek, et al., 2009), normalizing fasting blood sugar levels, normalizing blood pressure, normalizing blood lipids (Santos, et al., 2012), decreasing heartburn and bloating (Pointer, et al., 2016).


These studies show a potential for reversal of type 2 diabetes (Daly et al., 2006; Westman et al., 2008; Noakes et al., 2006) and polycystic ovary syndrome (Mavropoulos, et al., 2005; Gower, et al., 2013; Goss, et al., 2014; McGrice & Porter, 2017) , and improved markers of metabolic syndrome (Hession , et al., 2009). 



Do not weigh yourself. It is not an accurate reflection of fat loss. Weight is affected by water, lean muscle and bone mass, which fluctuates. Everyone is different; some people experience rapid weight loss while others lose weight gradually, meanwhile some people plateau sooner and others plateau later. 


Focusing on weight will not be constructive to the process in any way. It will only create stress and distraction, which will make fasting very challenging.


The focus of fasting for health reasons is on body composition and waist size. If change occurs too slowly in these areas or a plateau has been reached, fasting methods will require adjustment.




                       Preparing for the Fast



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Daly, M. E., Paisey, R., Millward, B. A., Eccles, C., Williams, K., Hammersley, S., MacLeod, K. M., & Gale, T. J. (2006). Short-term effects of severe dietary carbohydrate-restriction advice in type 2 diabetes--a randomized controlled trial. Diabetic Medicine : A Journal of the British Diabetic Association, 23(1), 15-20. doi:10.1111/j.1464-5491.2005.01760.x

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Eenfeldt, A. (2017). A low-carb diet for beginners. Lose Weight Using Intermittent Fasting. Retrieved October 13, 2017, from

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Fung, J. (2017). Blog. Retrieved October 11, 2017, from

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Hession, M., Rolland, C., Kulkarni, U., Wise, A., & Broom, J. (2009). Systematic review of randomized controlled trials of low‐carbohydrate vs. low‐fat/low‐calorie diets in the management of obesity and its comorbidities. Obesity reviews10(1), 36-50.

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