by Donald Ellsworth, M.D.
I love…fasting! You may not have heard love and fasting put together before but if you try it, you are likely to love it. Calorie reduction, not eating for part of the day or even several days, may sound extreme; however, keep in mind that water-only fasting has been done for safely for a millennium. Recently, numerous studies have been published showing fasting to be one of our best tools for staying healthy and even reversing disease. Fasting truly can be the fastest route to better health, fasting can improve your brain, heart, blood pressure, blood sugar, arthritis, inflammation, mood, autoimmune problems, migraines, allergies, cravings and more. Even outcomes of cancer therapy are improved with fasting.
People often skip this powerful “fountain of youth” because they assume it’s too hard. You will find options for water fasting as well as eating reduced calories that can be used in conjunction with many eating strategies including plant based, paleo and ketogenic. Despite the safety of limited fasting, prior to fasting I recommend you have a discussion with your medical provider.
Fasting Produces Cellular House Cleaning (Autophagy), Repair and Growth of New Cells
Why does fasting make such a profound effect on our health and likely our longevity? Fasting, as well as caloric restriction, promotes the ultimate cellular detoxification process referred to as ‘autophagy.’ Autophagy involves removing cellular debris which enables our body to work more efficiently, essentially acting “younger.” Incredibly, fasting not only cleans out our cellular debris but it also stimulates our stem cells to gear up and start rebuilding and repairing our body (i.e muscle, brain, immune systems). Finally, fasting also teaches our body to use fat for fuel, turning fat into ketones (ketosis).
Suggestions on How to Start Fasting/Caloric Restriction
Step 1: Intermittent Fasting (also known as time restricted eating)
Contrary to conventional wisdom, eating throughout the day often contributes to over-eating and disease. Restricting eating hours to a 10 hour window or less can dramatically improve health. Men and individuals with significant health issues may benefit from a shorter eating window of 6-8 hours. Generally, one should practice intermittent fasting only 5 days a week in order to ensure adequate overall nutrient intake and to prevent your body from adapting.
When should you be eating? While some studies show benefits with eating breakfast, this does not work for everyone. Other issues to consider are the timing of your eating – when your family eats together and when you are naturally hungry. You should avoid eating after 6-7 PM. Intermittent fasting/time restricted eating allows the body to start clearing your stores of sugar, start burning fat (i.e. making ketones) which results in lower glucose, triglycerides, inflammation and weight. Eating during hours of the day also allows our distended stomachs to return to a smaller size which helps normalize our super-sized American appetites.
Step 2: Occasionally, Eat Just Once a Day
This is an advanced version of the above intermittent fasting – you may want to do this 1x/week. When you eat only 1x/day it is really important to eat nutritionally dense foods like healthy fats (avocado) and the “G-BOMBS” that Dr. Joel Fuhrman refers to: Greens, Beans, Onions, Mushrooms, Berries and Seeds.
Step 3: Water Fast for 24 Hours
If you do well with intermittent fasting for 18 hours, just add 6 more and try to do this regularly, i.e. every 1-2 weeks. Water is the ideal drink but if you regularly consume caffeinated drinks, drinking a small amount can prevent a headache. You can also have a serving of herbal tea or Yerba Mate with Stevia if desired. Remember not to use juices, creamers or amino acid supplements as the goal is to actually be fasting.
Step 4: Short Term Fasting for 2-4 Days (again, we recommend you discuss with your medical provider)
If you did well with a 1 day fast, you are ready to try going 2-4 days in a row for more potential benefits. While fasting, it helps to exercise daily to stimulate fat burning and preserve muscle mass. By regularly fasting, your body’s stem cells become activated which helps regenerate and rejuvenate your body (more muscle fibers and improved brain function). I recommend you limit fasting to no more than 4 days per month. Interestingly, many find it is just as easy to fast 4 days as 2 because as you burn fat and make ketones, your appetite drops dramatically and energy often increases. Women usually go into ketosis after 2 days, men after 3 days. The 3-4 day fast can be repeated every 1-4 months. Note that fasting results in sodium and potassium loss, use water with sea salt to balance, see the final thoughts below.
Not ready for short term fasting?
You may want to consider the caloric restriction options below:
Calorie Restriction Options
Option 1) Calorie restriction several times a week: Studies have shown when calories are dropped every other day, health improves. In the studies, men eat 600/women 500 calories every other day. The non-calorie restricted days do not have any specific limits as how much is eaten or when, yet weight drops and labs improve. Benefits can even be seen if calories are restricted to just 2x/week, the so called 5:2 plan.
Option 2) The “Fasting Mimicking Diet” (FMD) is a well-researched, convenient, albeit, pricey plan which involves consuming specific reduced calorie meals packaged and sold through www.prolonfmd.com. The 5 day FMD can be done every 1-4 months.
Who Should NOT Fast?
A few groups should not fast, most are obvious: individuals with an eating disorder (anorexic or bulimic), children < 18, pregnant/nursing women, those who are underweight, the extremely frail, i.e. uncontrolled heart failure, severe kidney or liver disease. Also, those with certain metabolic disease like porphyria, and disorders of fatty acid metabolism. Individuals with type 1 diabetes generally should not fast as they need very strict supervision and monitoring. Those with type 2 diabetes can fast but if taking medications to lower blood sugar, these medications typically should be reduced or not taken while doing a water fast – please discuss this with your provider.
Fasting is a very powerful wellness tool and that most reasonably healthy, non-pregnant adults can do. Limit your 24 hour fasting to a maximum of 4 days/month (either in a row or spread out). You should generally feel well during a fast. During a 3-4 day fast, you generally would stay on your hormones and hold off on taking vitamins, unless you know stopping a vitamin will cause issues for you to stop (i.e. getting constipated off of magnesium, fatigue off of B vitamins). Adding some sea salt to replace some of the electrolytes you can lose during fasting can help you address headaches or energy slumps (1/4 tsp. to glass of water as needed or 1 tsp. to 1 gallon of water). If you have cramping, add potassium 99 mg 2 caps 2-3x/day. The extra energy you have doing a fast might make sleep a bit off, so extra magnesium or melatonin can help. If you lose too much weight, experience weakness or lightheadedness that does not respond to drinking more water with sea salt, you would want to add food back in. For more information see: “Fasting and Eating for Health” by Joel Fuhrman (note that Dr. Fuhrman includes information on more extended fasting beyond the scope of this article).
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