How to fast


We all fast.  An overnight fast terminates with a breakfast.  Fasting has always been a part of the human species.  We are all supposed to feast and fast.  When food was available, we had a feast, and when it was not available, we fasted for days at a time.  If we could not survive this fast, we would not have survived as a species.  The fasting did not weaken the organism because that would have facilitated the demise of that person.

On the contrary, it appeared to give the organism added benefits to survive, and even emerge as a more resilient organism.  We notice this in the animal species too, fasting appears to lengthen life span and induce other beneficial metabolic changes.  When animals are sick, they do not eat.  This fasting is also noted to benefit that animal by changing its physiology.  Even Hippocrates is quoted as saying that if you feed the patient, you feed the illness.  Fasting has been advocated as a means of treatment of multiple diseases including inflammatory conditions, inflammatory bowel disease, dementia, psychiatric illnesses, infections, hyperlipidemia, and diabetes mellitus, to name a few.

Today, we eat very differently from our ancestors. Our genetic material has not caught up to our current feeding frenzy eating every 2 hours.  We cannot evoke the physiology of fasting in our bodies if we are constantly in the fed state.  It is almost like having daytime all the time with no nighttime.  We now know that eating is followed by inflammation in our body.  Profound changes occur within the microbiota in our gut lining, inflammatory cells in the gut, hormonal production by various organs at every meal. Episodes of rest should follow these changes.

Eating frequently results in psychological addiction to the act of eating.  Rather than eating only when one is hungry, eating is initiated by the social circumstances; the time of the day, the company, and the environment amongst other things.

Further, certain food constituents are known to have addictive properties. These include sugar as the biggest culprit, resulting from the stimulation of the pleasure Center in the brain, very similar to the pleasure received from narcotics.  Hence, abstinence from sugar can result in withdrawal symptoms that are often very powerful. Therefore, we can see that changing the frequency of eating and the circumstances around meals, can be quite a challenge.  It is for this reason that I have outlined a method to initiate this intermittent fasting program.  I have asked the patients to become mindful of the symptoms that they are experiencing before eating. Are they eating because they are hungry, or are they eating because of habit, time of the day, social cues, or withdrawal symptoms? This in itself can be quite challenging.

Firstly, for the first 1-2 weeks, we must stop eating all sugars, processed foods, and eat mostly whole foods with an emphasis on whole plants.

Then, I encourage patients to skip meals. This is done randomly.  If you not hungry, skip the meal.  Notice how you feel.  Notice that there was no adverse effect from skipping a meal.  These should be random for the first week and one should be occasionally skipping dinner, lunch, or breakfast. This leads to the next step.

After this two-week introduction, choose 1-2 days a week where you choose to skip 2 meals in succession. This results in a 24 hour fast.  During the subsequent meal, I encourage my whole food predominantly plant-based diet, with no restrictions in calories.  That meal should be very satisfying.  Once you feel comfortable with this, you should try to have only one meal a day.  It is important not to snack in between meals.  Remember that every snack stimulates insulin and changes your physiology.  Any time you eat something you are changing your hormonal physiology.  You should drink plenty of water.  6-8 glasses of water is recommended per day.  Soft drinks must be avoided.  Caffeinated drinks are allowed in small quantities such as tea and coffee.  Sometimes some patients feel very tired and fatigued during this fast.  In the beginning, this could be a withdrawal from sugar.  Later on, it is probably related to dehydration and electrolyte loss.  If the blood pressure is low, rehydration and electrolyte replacement is needed with a small pinch of salt in a glass of water.  If you are taking medications, you should be monitoring your blood pressure and your blood sugar anyway.  You should call the office with any questions.

What about medications? One should discuss this very carefully with your physician/provider.  Antihypertensive medications, anticoagulants, psychotropic drugs, antianginal medications, are all allowed.  However, diabetes is a unique situation.  Insulin taken during a fast can result in low blood sugar levels.  If you are taking insulin, you have to discuss the program with your physician.  In general, my recommendation has been to reduce the insulin intake by 50% on the day of the fast and to take your blood sugar readings frequently during the day to make sure that you are not developing hypoglycemia.  Document the results and present them to your provider.  I usually allow Metformin to be continued, but typically discontinue all sulfonylureas agents.