So what is Intermittent Fasting (IF) all about? The new buzz in the town?
To start with, Intermittent Fasting (IF) is a real thing. Intermittent fasting was always there for 1000s of years in Dharmic and few other cultures. Hindus go on fasting on few auspicious days from sunrise to sunset or until they see the moonrise. Jains eat their dinner before sunset and wait till sunrise before their next meal. Muslims fast during their holy month of Ramadan from dawn to sunset. Jews fast on their auspicious days such as Yom Kippur. Our ancestors had always understood the benefits of IF and attached religious significance to it as our ancestors diligently followed religious codes.
The missing piece was the scientific basis behind the Intermittent Fasting which might have got lost due to the knowledge not being transferred appropriately over centuries. I should thank my friend, Hemanth Krishnan, who introduced me into IF and provided the insight into the scientific basis behind IF. Disclaimer – Most of the information is something I got from him as he is my guru in this space while I am a practitioner.
Humans by evolution were hunters who hunted for their food just like other animals. Food is not expected to be available for them everyday. So their bodies adapted over period to sustain themselves when the food is scarce and use food reserves in their body. Food reserves are stored when there are periods of abundance of food. So what are these food reserves which can be used by humans during the days when food is not available? These are the fat deposits in our body.
Over a period of time, humans learnt the art of agriculture and developed settlements and civilizations and started storing grains and other food which they cultivated. The days when they went without food reduced and the fat reserves never had a chance to be used.
Intermittent fasting is adhering to the evolution process i.e. create periods to deny food to the body so the body uses the fat reserves.
This can be anything from going without food for 16 hours in a day or eat just 500 calories 2 days a week or go without food for 24 hours in a week.
So how does the different food groups are used digested by the body?
Carbohydrates including sugar are digested and converted into glucose by the body in the first 2 hours. Insulin is secreted which is a sign for body cells to absorb the glucose in the bloodstream for energy needs.
Protein is digested for 2-4 hours and used up by the body for energy. Fat is digested for 4-8 hours. After the 8th hour, as the glucose in the blood gets low, the body signals the liver to dump the glucose stored in it to into the bloodstream to be used up by body cells as energy. This energy source is used for the next 2 ½ hours. After this glucose is depleted, body starts to get the glycogen from the body cells including the muscles and convert it into glucose and release it into the bloodstream. This energy sustains the body especially the brain for the next 2 hours. Once all these sources are depleted, the body turns to fat deposits and start to use them through a combination of processes such as lipolysis & gluconeogenesis where glucose is supplied to the brain while fatty acid cells are used up for muscle cells through fat oxidation.
There is a separate process called Ketosis (basis for Keto diets) where brain start to use ketones from the fat reserves. Sustained fasting beyond 20 hours and low carbohydrate diets will trigger this ketosis process. (can be measured by test strips to test ketones in the urine)
Questions can be raised what if body starts to use up body cells glycogen stores including muscle glycogen, wouldn’t the muscles get depleted? That is where the body is intelligent enough to secrete Human Growth Hormone (HGH) to preserve the muscle cells. HGH is an anti-aging hormone (have covered this hormone in https://randomvoyager.com/exercise/). Studies has showed HGH in the body increases significantly. Do note that the HGH depletes as one ages or is obese. This increase in HGH will help. Another benefit which happens is the body starts to destroy the bad cells like starting stage cancer cells through a process called autophagy. Cancer cells need lot of glucose unlike regular cells.
In summary, these are the benefits with Intermittent fasting –
- Weight loss 2. Insulin resistance 3. Cancer prevention through autophagy 4. HGH boost
My Experience with Intermittent Fasting
I started with 15+ hours of fasting per day. I.e. eat my dinner by 6 pm and have my breakfast after 9 am the next day which gives a gap of 15+ hours. Then I extended it to 16+ hours but did not go beyond 18 hours in the past 9 months of practising the IF. After 2 months of starting IF, I started my weight training to 2 hours after my dinner. I had consistently used the body composition monitor to measure the lean muscle weight so as I was careful not to lose muscle mass as weight training needs protein to start healing itself and giving rise to muscle increase. Though I did not gain muscle significantly I did not lose muscle and my strength increased as I could progressively increase my weights for different exercises. For example, I started deadlift in Nov 2018 at around 95 pounds but my July 2019 I was able to do deadlift with 225 pounds. (5-6 reps x 3 sets). Personally I consider IF as the primary weapon in the weight loss process.
So what is allowed to drink during IF?
One can drink anything which does not have calories in it e.g. black coffee, black tea. I drink water with lemon juice+Himalayan rock salt for rehydrating myself.
Caution – I would advise Diabetic patients to consult with their Physician before they start IF and also consistently monitor their blood glucose levels.
https://randomvoyager.com/weightloss/ – Beach Body with six pack at 47 years of age? Is It doable?
https://randomvoyager.com/diet/ – The diet plan I worked for weight loss