Interesting new insight on intermittent fasting

I've been a bit distracted and so haven't posted in a while.  I do hope everyone had a wonderful Christmas, Hanukkah, or whatever you celebrate.  This is a season of light and hope.

I have come across news on intermittent fasting that I thought was interesting.  It has to do with the gut-brain axis.  We've written before about the influence of the gut-brain axis on brain health.  Somehow, there is a two-way communication between microbes in the gut (bacteria and archaea) that regulates brain function.  Meaning that healthy gut = healthy brain.  Or something like that.

When we discussed intermittent fasting in Beating the Dementia Monster, it was credited by the sources I referenced with raising the level of brain-derived neurotrophic factor (BDNF) in the body.  BDNF not only repairs damaged brain cells, but it also prompts stem cells in the hippocampus to form new neurons.  BDNF is generated during sustained aerobic exercise, and so exercise is the most powerful tool in the Dementia Toolkit.

But, after reading an article in the New England Journal of Medicine, I was prompted to began a 20 hour/day (sort of) fasting protocol in 2020.  Intermittent fasting is not recommended for the elderly, because many of us have trouble maintaining an adequate weight.  But I am currently five pounds over where I want to be, and fasting appears to have been beneficial to me.  So I continue.

For the past year and a half or so, my memory and cognition have been tested weekly by researchers from the University of Washington's Alzheimer's Disease Research Center.  While I don't have access to their protocols for analyzing the data, I have no trouble telling that I'm doing just fine.  I've also found that I score best late in the morning, after some coffee, after the gym, but before eating anything.

So how do fasting, the gut-brain axis, and brain health intersect?  There was recent research from China published in the journal Frontiers in Cellular and Infection Microbiology finding an association between weight loss due to intermittent fasting and brain health.  The researchers correlated intermittent fasting, improvements in the health of gut microbiome (all those little things swimming around inside your gut), and brain health.  Long story short, intermittent fasting is good for the health of the gut microbiome, so the gut microbes do a better job of regulating brain activity.

Here's an article about the study from Newsweek -- a little easier reading than the journal article.  Most people do intermittent fasting for weight loss, so that's the context for the study.  But there are other reasons to fast, so I don't think the association with weight loss in either the Newsweek or journal articles are central to the phenomenon.  If you do all the things to support your gut, it will help your brain.  This Healthline article lists 10 things you can do to support your gut biome.  Notables include eating fiber, eating fermented foods (I eat kimchee and yogurt every day), eating whole grains, etc.

How does the gut-brain axis work?  It's pretty mysterious to me, but this passage from the Wikipedia article is interesting: 

"Chemicals released in the gut by the microbiome can vastly influence the development of the brain, starting from birth.  A review from 2015 states that the microbiome influences the central nervous system by 'regulating brain chemistry and influencing neuro-endocrine systems associated with stress response, anxiety and memory function.' The gut, sometimes referred to as the 'second brain,' may use the same type of neural network as the central nervous system, suggesting why it could have a role in brain function and mental health."  

Your body is truly amazing.