More on Intermittent Fasting

In my post of January 10, I wrote about a coincidence in which I'd gotten an email from my sister asking for my thoughts on intermittent fasting, and the same day Amy's nephew shared with us his success with intermittent fasting.  This prompted me to spend more time investigating it, since there was evidence that intermittent fasting is helpful with Alzheimer's disease.  (In Beating the Dementia Monster, we promote a daily 12-hour intermittent fast.)

But the coincidences keep on coming.

We returned home from spending Christmas with Amy's family in Hawaii, and I returned to my gym here.  My routine is to spend 50 minutes a day on the treadmill watching YouTube videos on various subjects.  These often relate to my interest in how to deal with Alzheimer's disease.  I often rely on YouTube to serve up what it thinks I'll like, and it seemed to perceive that I was interested in Intermittent fasting.

The other day, I was presented with a video on intermittent fasting that cited a recent article in The New England Journal of Medicine about intermittent fasting, "Effects of Intermittent Fasting on Health, Aging, and Disease."  I made a note to find the article when I got home.

Well, I got home and I was piddling around the house when the doorbell rang.  It was my neighbor, a retired physician (and reviewer for Beating the Dementia Monster).  He had in his hand a paper copy of the NEJM article that he had torn from his paper copy of the journal.  Quite a coincidence, but this article seems to be getting a lot of attention.

I am continuing work on the second edition of Beating the Dementia Monster, and I thought it well to address intermittent fasting.  Here is a preview of what I intend to say:

Intermittent fasting can take several forms.  A daily fast of 12, 16, or 20 hours every day is one possibility.  For the 16 and 20-hour fasts, this means forgetting breakfast and perhaps delaying lunch.  (Don't worry -- medical research has totally destroyed the idea that breakfast is the most important meal of the day.)  Some see the 16-hour fast as a stepping stone to the 20-hour fast.  With the 20-hour fast, you will then do all of your eating during a four-hour window every day.  Another approach is to eat normally five days a week but to only consume 500 calories each of two days per week.  For example, you might eat normally on Sunday, Tuesday, Wednesday, Friday and Saturday, but eat only 500 calories of food on Monday and Thursday.  Sound hard?  People I know who do this tell me that it gets easy after a couple of weeks.

But what’s this about?  An article appeared in the December 2019 issue of The New England Journal of Medicine that described intermittent fasting and what is being learned about it.  The article was entitled “Effects of Intermittent Fasting on Health, Aging, and Disease.”  It says that the practice of intermittent fasting improves glucose regulation, increases resistance to oxidative and metabolic stress, and suppresses inflammation.  Inflammation and oxidation are major factors in the development of Alzheimer’s disease.  Fasting elicits these effects as responses from cells in the body.

Intermittent fasting shares some traits with the increasingly popular (fad?) keto diet, about which I have no comment.  Both strategies lead to a condition called ketosis.  The article notes that glucose and fatty acids are the main sources of energy for the cells.  It goes on to say that, after meals, glucose is used for energy, and fat is stored as triglycerides.  During fasting, triglycerides are broken down to fatty acids and glycerol.  The liver converts fatty acids to “ketone bodies,” which, in the absence of glucose, provide a major source of energy for many tissues, especially the brain.  This is ketosis.  The ketone bodies also give you bad breath.

In the keto diet (if faithfully adhered to—a challenge), the body remains in ketosis.  However, during intermittent fasting, the body undergoes “metabolic switching” in which the body shifts in and out of ketosis.  It shifts back and forth between relying on glucose and fat for energy.

What are the benefits of being in ketosis?  According to the article, ketone bodies serve not only as fuel for the cells, but they also signal cells and organs to perform a variety of functions involved in health and aging.  Earlier theories about fasting focused on restricting calories for weight loss, but recent research points to a whole suite of other positive effects from not eating.  The article discussed positive effects for obesity and diabetes, cardiovascular disease, cancer, neurodegenerative disorders (like Alzheimer’s disease), asthma, multiple sclerosis, arthritis, and healing from traumatic injury.

Too good to be true?  I don’t know, but the 12-hour fast has been part of my regimen from the beginning.  I am currently experimenting with more aggressive fasts, and the research seems compelling.