3581366564_fb537e81a4_zAn elephant’s brain, at around a whopping 7,500 grams, makes our little 1,400 gram brain seem puny.  The animal’s brain represents 1/550 of its total body weight while a human brain is about 1/40 of the total body weight.  In other words,  a human brain represents about 2.5% of the body weight while the huge grey guy’s brain is about .18 % of its body weight .  That big brain is not so impressive now, huh?

While only representing a small percentage of our body weight, our brain uses 22% of the body’s energy expenditure even while at rest!  Bottom line is: it takes an awful lot of calories to keep the human brain running.  Thankfully, having such a large and powerful brain has allowed humans to develop the skills to provide a pretty constant food supply for it most of the time.

Our capability to evolve as a species was largely dependent on our ability to provide food for our brain on a regular basis.  Imagine early humans migrating across the land, competing for survival among animals with smaller brains, but bigger teeth, sharper claws and much greater speed.

Our early ancestors had one advantage over the other animals that even our closest primate relatives didn’t have.  We developed the unique ability to feed our brains with an alternative power supply other than direct food at frequent intervals.  Some believe this to be the reason Homo Sapiens survived and the Neanderthals disappeared even though they had larger brains.

Superfuel For Your Brain

Normally, our brain is energized by steady stream of glucose  delivered from glycogen, which is stored glucose primarily found in the liver and muscles. A regular supply of glucose is provided by breaking down muscle when necessary, not exactly a good thing for a hunter gatherer who may have to travel miles searching for food and go days in between substantial sustenance.  After about three days without food, the liver starts to use body fat to create chemicals known as ketones which is a highly efficient fuel source for the brain and would’ve allowed our ancestors to continue hunting and functioning even when food was scarce.  Ketones aren’t just fuel.  They are superfuel.

In their book, Power Up Your Brain, David Perlmutter and Alberto Villaldo write:

Perhaps the most important dietary consideration related to optimizing the brain, enhancing neurogenesis, and providing a fertile environment for the process of neuroplasticity, so necessary for building new neural networks, is calorie reduction.

For this reason, in the book, they advocate reducing caloric intake and/or intermittent fasting. Fasting shifts the brain from using glucose as a fuel and turns on this alternate process.  Fasting even reduces brain cell suicide (apoptosis), reduces brain inflammation, enhances detoxification, reduces free radical production and increases mitochrondrial replication and ability to generate energy. In the book, they go on to say:

Fasting is powerful medicine well beyond anything even remotely considered by modern pharmaceutical science. Indeed, the concept that dietary choices are healing is embodied in this famous quotation from the father of Western Medicine, the ancient Greek physician Hippocrates: “Let food be your medicine and medicine be your food.”

They define fasting as the abstinence of all food for a defined period of time at regular intervals. They do allow water and prescribe fasting in one day increments as outlined in the “Power Up Your Brain Program” in their book.  Of course, they also stress that it is important to check with your  physician before engaging in a fasting program. Reducing caloric intake on a daily basis will achieve the same desired effect they advise. Recent studies are also showing that fasting is beneficial in other ways as well.

image source: https://www.flickr.com/photos/arnolouise/


    • Debbie Hampton Reply

      Yes, there are so many reasons to not over indulge in food. It seems it is good all around for us!

  1. Ande Waggener Reply

    Fascinating post, Debbie! I knew that fasting has a powerful impact on mental clarity but didn’t know why. Makes total sense. Many years ago, I did a 3 month juice fast, mostly as a spiritual/inner growth thing. My mind was so clear during those three months! Unfortunately, that long without food triggered old binge responses and it was part of what catapulted me to my current state, but I can attest to the power of fasting … in shorter spurts! 😉

    • Debbie Hampton Reply

      I can see how it would do that…especially with a 3 month juice fast. I found this information fascinating. I had never heard of ketones before.

      I naturally tend to not want to eat much. For me, it is kind of like a chore. I actually went on a gain weight diet two summers ago. I love being able to have this info in my hip pocket. However, I cannot seem to even make it through the one day fast they recommend.

      The bottom line is we have to have a healthy relationship with food physically and mentally.

  2. Debbie Hampton Reply

    It seems the wise men of some ancient traditions knew this all along, huh? How in the heck did they know? Our relationship with food as a society has gotten so skewed and out of whack.

    This may sound kind of extreme to some, but I feel it is right on target to fast. Food should be for sustenance. We tend to use it for everything but that. Most of us are fortunate enough to not even know what hunger is, but that is a double edged sword.

    Thanks for sharing the site. No, I had not heard of it before. Interesting. Sad to see the dog and cat so far down on the list.

  3. Debbie,
    This comparison between the elephant and human brain is fascinating. You really have a gift for boiling down complex ideas and making them easily understandable.

    It seems that calorie restriction is a good idea all around. In addition to benefiting the brain it is also said to increase longevity. Fasting can be very beneficial for many people, in particular the hearty types. I don’t find it a helpful protocol for people who are deficient. I tend to resonate with approaches that identify our different constitutions (like Chinese Medicine and Ayurveda) and treat accordingly. I believe that fasting can be used more effectively if you know your basic constitution.

    Thanks for this interesting look at food and the brain.

    • Debbie Hampton Reply

      Thanks! I just simplify the information and relay it in terms that I can understand. I have to “water it down” for myself, and I do not want to make it complicated, complex reading. I do not like that myself. My goal is to educate people without them knowing they are being educated.

      I agree with you that each person has to be sensitive to their own basic constitution and know what works best for them. It is so smart of you to be aware of and follow that which works for your body. If one does not heed their own body’s wisdom, it is way too easy to get swayed by every food fad that comes along. I really prescribe to the eating healthy and less, but the fasting not so much!

  4. Debbie,
    This was fascinating. I know limiting caloric intake has many benefits in prolonging life due to the reduction of inflamation which is the root of many diseases, but I had no idea it was so beneficial for the brain.
    Wow! Thank you so much for sharing this knowledge with us.

    • Debbie Hampton Reply

      Thank you for stopping by and for your thoughts, Angela. The benefits of listening to our bodies’ own wisdom and getting back to what is innately good for us, which is not the basis of most of our modern lifestyles, goes on and on it seems.

  5. Great info. The brain also use about 25% of the body’s available oxygen supply. Breathing properly, staying relaxed and calm, and water can ensure the brain sufficient oxygen to work effectively. Keep ’em coming.

  6. Raji Lukkoor Reply

    wow. Great information. It gave me real perspective on why fasting is such an important part of the Indian fabric. Thanks.

    • Debbie Hampton Reply

      Wonderful, Raji. Like a lot of ancient practices, science validates what people already somehow knew.

Write A Comment

Pin It on Pinterest