Fasting & Ketosis Glass of water

Fasting & Ketosis

Grandma had it right

Back in the good-old days when families used to sit down to eat their meals together, people would eat breakfast at 8am and dinner by 6pm and then not eat again until breakfast the next day.  The word “break-fast” refers to this natural evening cycle of going without food.  This 12 to 14 hour period of not eating each day was a very important factor that contributed to maintaining a relatively trim population of Americans.  Today, people are eating and snacking constantly, some eating six to ten times a day.  They never give their bodies a break from eating and digesting until they are asleep and even then, some get up to grab a midnight snack!

Health Benefits of Fasting

Taking a break from food naturally cuts down the amount of food eaten in 24 hours and gives the body a chance to heal itself.  When the body is not concentrating its energy on digestion a wonderful process known as autophagy begins. The amazing body starts to get rid of toxins and old, damaged cells, and replaces them with new healthy cells. Literally meaning “self-eating,” autophagy is the consumption and recycling of the body’s own tissue for health and rejuvenation. Ten other amazing health benefits from fasting include:

  • Weight-loss/fat loss
  • Lower blood sugar
  • Lower blood cholesterol
  • Lower blood insulin
  • Improved mental clarity
  • Improved concentration
  • Increased energy
  • Reduced inflammation
  • Potentially lengthened lifespan
  • Reversing type 2 diabetes! Jason Fung, MD, author of The Diabetes Code, has helped over a thousand patients overcome obesity and type 2 diabetes using fasting.

Fasting & Ketosis

Biologically, you don’t enter a true fast until after 30 hours because the cells are still being fueled by the glucose in the last meal you ate. When starting the keto diet, you can enter ketosis quickly by fasting for 36 hours. This can be achieved by starting your fast after dinner at 8pm, not eating the following day, then breaking your fast at 8am the next morning.  This will stop your carbohydrate/sugar cravings and jump start you into your diet by putting you right into ketosis!

Intermittent Fasting

If you don’t want to jump right into a 36 hour fast, implementing a daily 12-16 hour fast, called “intermittent fasting” or “reduced-scheduled eating,” has a great impact on health and weight-loss.  Here is an example of how you would do it.  Stop eating after dinner by 8pm, then don’t eat until at least 8am. Try to stretch this out until noon or even 2 or 4pm.
Different intermittent schedules are described as follows:

  • 12/12 – 12 hours fasting and 12 hours eating – best for weight maintenance
  • 16/8 – 16 hours fasting and 8 hours eating – commonly used in the keto diet
  • 20/4 – 20 hours of fasting and 4 hours of eating – an even more aggressive approach

Many people eating the keto diet try to do a 16/8 every day. Some people do a 24 hour fast twice a week.  This can be achieved by starting after dinner, skipping breakfast and lunch the next day, then eating dinner again at the same time you ate dinner the night before.

You Can Do It!

We have been told that breakfast is the most important meal of the day and to never skip it, but the truth is, you should totally skip it! Of course, you know your health limitations, but try to stretch your fasting period as long as you can.  Drinking liquids with added fat may help you go longer before eating.  You might try organic green tea or coffee with coconut oil in it and sweetened with stevia instead of sugar.  Bone broth is another liquid that is full of fat and salts that could help you stretch your fasting period.  While drinking just water is the best way to fast, these liquids are super healthy alternatives that will satiate you and give you energy.  Also, if you get headaches or dizziness, take extra salt in your water.  If your stomach gurgles, take mineral water.  For sore muscles, cramps and constipation, take magnesium.

Amazing Health Benefits of Extended Fasts

Some say there is no need to fast longer than 16 hours, but research done at the University of Southern California has confirmed that longer fasts can unlock greater healing potential in the body.  In an interview with Blue Zones called “Fasting for Longevity, 9 questions for Dr. Valter D. Longo,” Dr. Longo talks about his study on yeast and mice, then conducting a human clinical trial to observe the health effects of fasting.  In the yeast, fasting increased longevity.  With the mouse study, Dr. Longo said, “When fasting was done only twice a month for four days these mice lived longer and had about half of the cancers. When they did develop cancer, they developed it later in life. Cognitive performance improved, they had less inflammation, and they lost fat specifically in the abdomen.”
In the human study, Dr. Longo implemented a fasting-mimicking diet or FMD.  In an article by CNBC called, “Fasting: A trending food idea and new frontier in longevity science,” Dr. Longo reports that the results showed a reduction in body weight and body fat and a reduction in IGF-1 hormone, which accelerates aging and disease. The clinical trial also showed a decrease in C-reactive protein, a marker for inflammation, which is associated with diseases, from heart disease to cancer. At the end of each FMD period, blood glucose levels were 40% lower, a finding that researchers say may show that fasting can help with diabetes and other degenerative diseases.  Another amazing find in this study revealed that fasting for 3 to 5 days increased production of stem cells, or undifferentiated simple cells in the body that are able to regenerate into any one of various kinds of cells.  These stem cells promote healing and anti-aging.
Dr. Longo suggests that a healthy individual who exercises, is the perfect weight and eats a healthy diet may need to fast this way twice a year. Somebody that has high fasting glucose, high blood pressure, is over-weight or obese, or has a high risk of cancer in the family, probably needs to do it once a month (see “Fasting for Longevity, 9 questions for Dr. Valter D. Longo”.)  However, if you want to water fast for 5 days, I strongly encourage you to know your body and its limits or even do so under medical supervision. See “My 5 ½ Day Fast
Dr. Longo sells a packaged 5-day diet of foods that mimic fasting called Prolon. This regiment achieves the same results as water fasting, but can be done without medical supervision and is easier to do than going completely without food.  It costs around $300 a week. The foods are low in calories, sugars and protein but high in unsaturated fats. Included are plant-based energy bars, soups, a variety of snacks like olives, drinks like hibiscus tea and supplements like plant-based omega-3 fatty-acid oils and vitamin powders.  The total daily caloric intake is 770 to 1100 calories.  His website is

Don't Worry-You Won't Lose Muscle

Fasting is not starving.  This ancient practice is the voluntary avoidance of food for a beneficial outcome.  Our bodies have been adapted to go through periods of feast and famine.  Fasting helps us achieve a healthy weight while maintaining muscle mass.  Dr. Jason Fung, MD, author of The Complete Guide to Fasting said, “One of the main worries of fasting is the loss of lean body mass, or muscle. Many studies have been done on this and these fears are largely misplaced. In one study, fasting every other day did not produce any loss of lean body mass over 22 days, even as body weight steadily decreases.”  Typical adult Americans are packing around 30 to 60 days of stored energy in the form of fat on their bodies.  Think of fasting as eating up all those stored meals you are carrying around with you every day! It is important to remember that the body takes great care to package body fat in a readily available form so that when it doesn’t have food it can easily burn it for fuel.  It will not turn to eating its own muscle when it has so much fat to burn first.

6 Tips to Remember

  • Stay hydrated while fasting especially for extended fasts. Drinking lots of water can help curb the hunger and if you are suffering from a chronic disease you may be very motivated to heal.
  • Continue taking your vitamins and minerals to keep up your micro-nutrient levels.
  • Ease back into eating food again, especially for extended fasts because your body needs to adjust to digesting food again. Start with bone broth, then add in small amounts of easily digested foods like cooked vegetables before moving to heavier foods like meat.
  • Avoid binging when coming off a fast or you may get a belly-ache.
  • Replenish your electrolytes (sodium, potassium and magnesium) to support the body and get your bowels moving again.
  • If you are under 18, pregnant, nursing or under-weight, you should not fast. If you are taking medications, only fast under a doctor’s supervision.

The ancient, lost art of fasting is making a come-back as more and more people unlocking its healing and weight-loss potential.

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