by Sherif

Editor's note: this article is 5 years old, written long before existed but it's still relevant and will be revised. At this time, I was already pursuing post-graduate doctoral studies, so I had my research helmet on. One of the most interesting concepts around fasting is that it unlocks benefits hidden in our DNA. Like X-Men, certain conditions create proteins and alter our physiology to make us smarter, live longer and just plain more resilient. Hope to look at heat-shock proteins and saunas next!


  1. Fat in the swinging 60s

  2. Epic progress! Lose fat by eating more (?) 

  3. Fasting for athletes 

  4. David vs Goliath

  5. Research rant  

The 9th century Persian scholar Sahl al-Tustari was asked about a man who ate once a day, and he replied, “This is the way of the prophets.” Asked about someone who eats twice a day, he said, “This is the way of the righteous.” Finally, he was asked about someone who eats three meals a day, and he replied, “Build for him a trough!”  

I.Fat in the swinging 60s

It seems that the old solutions are always making a comeback. And for every topic there’s a story of how we’ve gone astray from a more intuitive, natural, and ultimately more correct way.  

Remember the decade “of irresponsible excess and flamboyance… the swinging sixties?” Sexual taboos were relaxing, and racism against blacks was taking the back seat on the bus, finally. Husbands, say so long to your wives, let them fix your tie and give you a kiss before you go to work or Vietnam. Wives, well, you know how to make a home don’tcha? Well aware that his TV audience was mostly women, Jack Lalanne would often demonstrate ridiculous physical feats like one-handed superman pushups and then jokingly say to the camera “but don’t try that yourself! Wait for your husband to come home and then tell him to do it.” 

Regarding happiness in the 1960s, Jack Lalanne’s theory is that “people have gotten so far away from the natural way they should be living, that they have lost the ability to be happy.” Jack was their Oprah, except he didn’t get fat. “Do you know that the average person has no conception of what this wonderful body that the good lord above has given us is, what it’s made of, and what to eat to keep it in repair? . . . Go down to your supermarket, and just watch the people as they buy groceries . . . You’ll see that the healthy, happy, handsome people have the natural foods in their cart. And the people completely out of condition, miserable and unhappy, look in their carts and see how many man-processed, high calorie foods they have in their shopping bags!” Jack Lalanne says (video 1 below). 

Or he might talk about the “sugarholics” who can’t hold their sugar. There are “millions and millions of them. As you go around the school yard… see how many of these children are soft with weak muscles... Their bodies are being made of this sugar they’re eating so they look soft and weak!” (video 2 below) 

II. Epic progress! Lose fat by eating more (?) 

My first impression at the above excerpts is “what processed foods did you think you had back then Jack?” My second thought is that if you subtract the Beatles, that jump suit and give Jack a cell phone, he could be today’s nutrition and fat loss spokesman, 50 years later. Where’s the innovation and the epic progress? Thirdly, someone could get sued for hurting someone’s feelings, speaking that bluntly. 

For too much of the information we’re given, especially regarding fitness, we’re offered the same trends in cycles. There’s a rush of elation at the transition from autumn to winter, or winter to spring, but we just encounter the same 4 seasons again each year with just enough time between to forget how the snowflake falls.  

Now people ask paradoxically “what can I eat to lose weight?”  We all fall for it. And while grazing has been the focus for health in recent years, an unhealthy, life consuming pattern of eating, where too much time is allotted to the task of eating up to 5/6 meals in a day, there is a new trend emerging; a tradition of the stuff of warriors, kings, saints and prophets.  

III. Fasting for athletes

The first time I became academically interested in fasting was during a 4th year  class I took while completing my specialization in neuroscience at UofT. The rampant eating of meals in body building circles hadn’t become popular yet, and I was learning about fasting as the only plausible way science has shown to prolong life (you could also try living in very cold temperatures, but that’s not plausible). In my mind fasting=longer life. The research read that “restricting food intake to a level below that which would be consumed voluntarily results in a decrease in the rate of aging and an increase in average and maximum life span.”  Fasting is also turning out to be a sort of magic bullet for disease, much like exercise. In addition to “[reducing] cancer formation and kidney disease [ fasting is relevant in neuroscience because it] increases the resistance of neurons to dysfunction and degeneration in experimental models of Alzheimer’s and Parkinson’s diseases as well as stroke” (Anson et al, 2003).  

In addition to “[reducing] cancer formation and kidney disease [ fasting is relevant in neuroscience because it] increases the resistance of neurons to dysfunction and degeneration in experimental models of Alzheimer’s and Parkinson’s diseases as well as stroke” (Anson et al, 2003).  

When you look at the research done with rats, it’s as if anything you do to these poor critters can be made more tolerable and result in longer life with fasting. Whether you give a rat Alzheimer’s, Parkinson’s, Huntington’s, Epilepsy, Diabetes or Myocardial Infarctions (heart attacks), the rats that fast live longer and better. For example, “after 100 days of MI [heart attack], there were only 4 deaths among 32 rats in the intermittently fasted group versus 24 deaths among 31 normally fed rats” (Katare et al, 2009). 

“after 100 days of MI [heart attack], there were only 4 deaths among 32 rats in the intermittently fasted group versus 24 deaths among 31 normally fed rats” (Katare et al, 2009). 

Why should an athlete care about fasting?  

  • The first limiting factor in the achievement of goals, fitness or other, is life. Fasting prolongs life. 
  • The next limiting factor in any of our endeavours is having a healthy brain functioning in a manner that allows the remembrance and initiation of plans to achieve goals. Old men still achieve great things. However, one cannot achieve a goal they cannot remember. Fasting protects against Alzheimer’s and stroke. 
  • Parkinson’s and Huntington’s are diseases that adversely affect the motor system. Since disease and health are like two extremes on the same continuum, protection could mean enhancement.  
  • Where skills are required, the ability to remember them leads to better execution of them. Fasting protects against diseases that cause memory loss like Alzheimer’s. 
  • Competition is stressful. Fasting protects against stress. 
  • Fasting with exercise creates the loss of fat, making those that fast leaner with less toxins that could be contributing to obesity (toxins accumulate in fat), but this will have to be discussed in another post. 

The next question is just what kind of fasting will yield the benefits? Some research points towards intermittent fasting, or alternate day fasting, sometimes referred to as EODF (every other day feeding); 

For example, Anson and colleagues note that there is something unique to the intermittent fasting versus just decreasing food intake overall that resulted in the benefits. There’s something in the period of starvation followed by a small window of overeating (breaking the fast) that causes the protective effects which “do not occur when meals are more frequent.” From Anson’s 2003 abstract, “intermittent fasting resulted in beneficial effects that met or exceeded those of caloric restriction [overall dieting] including reduced serum glucose and insulin levels and increased resistance of neurons in the brain to excitotoxic stress.” Even if in the long run the rats fasting every other day eat the same amount as those that eat as they please, the fasting rats still benefit, or in the researchers’ words “intermittent fasting  therefore has beneficial effects on glucose regulation and neuronal resistance to injury in these mice that are independent of caloric intake.” 

The HOW is debatable though, but there are a few decent explanations. Mattson (2005) notes that intermittent fasting stimulates the production of brain derived neurotrophic factor (BDNF), which “plays roles in feeding, learning and memory, locomotion, stress responses, and affective behaviors.” In short BDNF is a sign of being smart and able to handle stress, though it’s unclear whether the intelligence and steadfastness come before or after the BDNF. “BDNF [makes you smart by] promoting neuronal differentiation and survival, synaptogenesis, and synaptic plasticity [and] BDNF expression in the hippocampus [where memories are made] increases in response to cognitive stimulation and EODF.” Make more BDNF playing Sudoku and fasting! Conversely, where there’s chronic uncontrollable stress, you find decreased BDNF. Also, there’s decreased BDNF levels with Alzheimer’s, Parkinson’s, and Huntington’s diseases. 

IV. David vs Goliath

David, “a man of fine feature and short height with blue eyes, and a ruddy complexion,” is the original example for the person wondering “can the small ever defeat the large?”   

Regarding the prophet David, the prophet Muhammad said that “the best prayer to God is the prayer of David, and the best fasting to God is the fasting of David; he slept for the first half of the night, woke up for one-third of it to pray, and then slept for the remaining one-sixth. David fasted every other day, and whenever he met his enemy, he never backed off.”  

Regarding food, Muhammad also tells us that “the best food a man could eat is that earned by him, and the prophet of God David ate from what he earned from his own hard work.” Really, the majority of those eating 5 or 6 meals struggle to make all that food while functioning productively in society: mothers, fathers, siblings, spouses, convenient school/work meals and family jams sustain the grazing. There are many benefits to being independent in the kitchen. And who’s washing all those dishes? 

I’ve heard boxing coaches say “a little hungry is better than a little full” before a match and a Judo coach told me that a bit of fruit is all you need before practice. I’ve personally found that mammal meat really slows me down before most tasks. There could be psychological and biological factors that enhance performance while working on less, like an ancestral drive to figure out how to capture that animal, or heightened senses. People say that the hungriest fighter wins the match. While fasting might not be for everyone, it has multitudes of physical benefits and can be a liberating experience from the urge to constantly buy and consume. In the very least, it worked for David. 

Check the References for an excerpt of the original underdog’s battle with Goliath, from Ibn Kathir’s Stories of the Prophets. 

V. Research Rant

When it comes to the research adding to what we know, the quest for truth can be complicated by the constant pressure to publish new, significant results.  People do not want to hear (or pay for) the story of how we looked in the wrong direction, and so researchers try hard to avoid telling that story.  Conversely, companies are willing to pay for significant results to be published in the most positive light, like in that study I read about chocolate expanding blood vessels and improving circulation. It took me a while to realize that it was funded by Hershey’s, which may not make the results false, but explains the exaggeration.  

And since authors need to get paid to live, often frugally, the looking glasses become constricted. Do we focus too much on what can’t implement? “I think I see something!” exclaims the researcher, staring at some part of another part. We’re the great experts of parts. We isolate: components of our food become pills and powders, we exercise one muscle without regard for the other, we work and study in cubicles, and live ignoring our neighbours. Forget the polymaths. Now a PhD might not know how to cook, while an engineer can’t differentiate a liver from a spleen. We could use a science of connecting disciplines. 


David vs Goliath, excerpted from Ibn Kathir’s Stories of the Prophets

When the two armies faced each other, Goliath challenged any soldier from King Saul's army to single combat, as was the custom of battle in those days. Goliath also wanted to show off his strength. The men were terrorized, and no one had enough courage to volunteer. The king offered the hand of his pretty daughter in marriage to the man who would fight Goliath, but even this tempting offer did not change the deadly silence among his soldiers. 

Then, to everyone's surprise, a youth stepped forward. A roar of laughter echoed from the enemy's side, and even Saul's men shook their heads. 

The young man was David (Dawud), from the city of Bethlehem. His elderly father had chosen three of his sons to join Saul's army. He had instructed the youngest one, David, not to take part in the fighting but to help the army in other ways and to report to his father daily on what was happening on the war front. 

Although Saul was very impressed by the youth's courage, he said: "I admire your courage, but you are no match for that mighty warrior. Let the strong men come forward." David, however, had already decided and was willing to meet the challenge. Proudly, he told the king that only the day before he had killed a lion which had threatened his father's sheep, and on another occasion he had killed a bear. He asked Saul not to judge him by his appearance, for he feared no man or wild beast. Saul, surprised by young David's brave stance, agreed: "My brave soldier, if you are willing, then may God guard you and grant you strength!" 

The king dressed David in battle armor and handed him a sword, but David was not used to wearing battle dress. He felt uncomfortable in it, and it obstructed his movements. He removed the armor, then collected a few pebbles and filled his leather pouch with them. He slung it over his shoulder next to his sling. With his wooden staff in hand, he began to walk towards the enemy. Saul was worried and asked him how on earth, with a sling and a couple of stones was he going to defend himself against the giant? David replied: "God Who protected me from the claws of the bear and the fangs of the lion will certainly protect me from this brute!"