Fasting in mood disorders: neurobiology and effectiveness. A review of the literature

Written By Claire C

This article reviews past literature related to the biological mechanisms that are activated during periods of fasting.  It specifically focuses on the potential positive effects of fasting on mood.  

Published in October 2013 in the journal Psychiatry Research.  Access the original article here: Fasting in mood disorders: neurobiology and effectiveness. A review of the literature

A brief summary:

What were they interested in? The authors were interested in looking in the literature to understand if fasting was associated with improved mood or reduction in depression or anxiety symptoms.

What did they do? The authors note that looking for studies that specifically linked fasting with “mood” or “depression” was too limiting; therefore, they focused their efforts searching for literature and studies that show fasting’s effects on neuro-biological mechanism that have been linked to enhanced mood and improvement in depression and anxiety.

What did they find? Given the lack of controlled, high quality studies specifically linking fasting and mood, there isn’t a firm statement such as “fasting improves your mood” that can be drawn. However, there were several studies that suggested that fasting significantly enhanced brain pathways responsible for feelings of well-being.

What direction could be next? It isn’t know whether fasting affects these biological pathways in a long-term (persistent) way, or whether it is a short-term (transient) effect. A specific study that focusing SPECIFICALLY on fasting and its effects on mood could be used to answer this question. Until then, we have indications of effect, but not firm conclusions.


History of Fasting and Mood:

  • Until recent times, humanity was used to large fluctuations in the availability of food
    • This often led to periods of over-feeding and starvation 
  • Periodic fasting is still practiced around the world, although mostly for cultural or religious reasons 
  • Hippocrates offered fasting as a treatment of acute and chronic diseases 
  • Therapeutic fasting has been considered a safe medical practice for more than a century 
  • Deliberate fasting has been observed to increase mental alertness, sense of calm, and positive mood
    • Mood alleviation may be related to an adaptive response promoting a search for food 

Methods of This Study on Fasting and Mood:

  • Checked scientific databases for articles related to fasting’s effects
    • Then selected 92 relevant articles for review 
  • Important background: what is a review article?
    • Research articles (primary sources) report the methods and results of an original study performed by the authors
    • Review articles (secondary sources) synthesize and analyze research already conducted in primary sources, but don’t original research of its own

Mechanisms of Mood Improvement During Fasting:

  • Long periods of fasting activate pathways in a similar way to a biological stressor
    • Activates the hypothalamic-pituitary-adrenal axis (HPA)
  • Mechanisms of this activation may include
    • Reduced cerebral glucose
    • Reduced insulin and leptin levels
      • Changes in leptin levels has already been identified as a signal of biological adaptation to starvation, and is associated with mood disorders
    • Sensation of hunger
  • Previous studies have also shown that fasting increases the availability of serotonin
  • Release of endorphins found after fasting
  • May be due to improved sleep caused by fasting 
  • Production of ketone bodies 

Proposed Benefits of the Relationship Between Fasting and Mood:

  • Improvement in sleep quality
  • Improved mood
  • Improved concentration
  • Decrease in migraine symptoms 
  • Decrease in pain sensation 

Limitations to Keep in Mind:

  • Need to perform randomized controlled clinical trials 
  • Findings are promising, but a direct relationship cannot be determined without meta-analysis
    • Not possible given the heterogeneity of available studies 
    • Heterogeneity: variability in the methods and population used in the study that make it difficult to make direct comparisons of studies’ results 
  • Unclear if mood improvement is sustained over time or if it is a temporary effect 

Other Fasting Flamingo Resources You May Enjoy:

  • Why fasting bolsters brain power
    • In this TED Talk, Mark Mattson, who currently serves as the Chief of Laboratory Neuroscience at the National Institute of Aging, discusses how intermittent fasting is good for your brain.  He discusses both anecdotal and evolutionary evidence that fasting improves mental efficiency.
  • The Fasting Talk, Breathe, and Distract Method
    • In this article, fellow intermittent faster and author Mimi discusses one of her favorite strategies for getting through a tough fast. Mimi, who has already lost over 70 pounds through fasting, believes that the fasting lifestyle can be easy and fun, and we here at The Fasting Flamingo agree!
  • Eat, Fast, Feast
    • Why did most Christians stop fasting?  And, is this ancient practice something the church should consider resurrecting? Dr. Jay W. Richards explores these interesting questions in his book as well as some of his own journey with fasting and a ketogenic diet.

Do you have content that fits with this blog and would like to share it?

All Topics

fasting flamingo

Read more content like this

Fasting Safely – Here’s what to know

Fasting Safely – Here’s what to know

In this article, Dr. Jason Fung discusses some of the most important things to keep in mind in order to fast in the safest way possible. He discusses some of the most common dangers associated with improper fasting and gives advice on how to prevent these. Most importantly, he discusses the importance of fasting with knowledge and experience and the power of easing into fasting. If you ever feel concerned about your own fasting practices, remember we’re here to help and provide you with advice and resources to make sure you have a positive experience with fasting!

read more
Eat, Fast, Feast

Eat, Fast, Feast

Eat, Fast, Feast – Heal Your Body While Feeding Your Soul – A Christian Guide to Fasting :: Why did most Christians stop fasting? And, is this ancient practice something your should consider adopting to strengthen your connection to God?

read more
The Joy of Fasting – Rumi Poem

The Joy of Fasting – Rumi Poem

There’s hidden sweetness in the stomach’s emptiness.
We are lutes, no more, no less.
If the soundbox
is stuffed full of anything, no music.
If the brain and belly are burning clean
with fasting, every moment a new song comes out of the fire.
The fog clears, and new energy makes you
 run up the steps in front of you.

read more
My favorite Intermittent Fasting Books – The 37 Best & Most Useful

My favorite Intermittent Fasting Books – The 37 Best & Most Useful

In the early 1900s there were a number of book published on fasting, but then there were very few new books on fasting or intermittent fasting until 2002 when Ori Hofmekler came out with The Warrior Diet. Then and starting in 2016 Intermittent Fasting books started popping up everywhere…

read more

Share this post with a friend

fasting flamingo

Leave a message


Submit a Comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.