Fasting is one of the most popular diet trends right now. Whether it’s 16:8 intermittent fasting, 24-hour fasts once a week, or simply eating with the sun, many people are looking to use fasting for improved health.
Now, people fast to improve their health, both physically and mentally.
And in this article, I’m going to cover how fasting impacts mental health. You’ll see how, as with most things, there isn’t a one-size-fits-all protocol.
Fasting can have benefits for mental health, but it can also have drawbacks. As such, you’ll see how to do fasting (if at all) if you want to improve your mental well-being and reduce anxiety, stress, and depression.
Fasting Overview
Fasting simply refers to a period of time without eating. During this time, the body relies on stored fuel sources for energy. Additionally, certain cellular repair processes can happen due to autophagy and other mechanisms.
If the fast is long enough, the brain and body begin to rely primarily on fatty acids rather than glucose. Although the body may also break down stored glycogen to be used as well.
Obviously, the longer the fast, the greater the physical demands are on the body.
Potential Benefits of Fasting on Mental Health
Fasting can have certain benefits for mental health, but not in all individuals.
Mental Clarity
One of the first potential benefits is improved mental clarity. Some people may find that switching over to fatty acids for fuel instead of glucose provides more sustained energy as opposed to the ups and downs of using glucose for fuel. This could also lead to less brain fog in some people.
Decreased Inflammation
Time-restricted feeding also may induce antioxidant and anti-inflammatory effects, mainly by switching over from glucose to ketones (fatty acids) for fuel. This may decrease inflammation in the brain and in the gut, which is important since it reestablishes the health of the gut-brain axis.
These effects may lead to reduced anxiety, depression, and other mental health problems.
Better Sleep
Also, fasting can potentially improve sleep, especially if you have your last meal a few hours before bedtime. Doing so allows the body to get into deeper sleep more quickly. And this may lead to improved mental health, energy, and alertness the next day.
Drawbacks of Fasting for Mental Health
Despite the potential benefits, there are also a number of drawbacks to fasting on mental health, especially if the fasts are prolonged (over 14ish hours).
Increased Cortisol
For one, fasting increases cortisol levels because this hormone is needed to mobilize stored energy for fuel. Since you’re not eating anything, the body has to get fuel from somewhere.
Yet, cortisol is a major stress hormone. And while it’s certainly needed, one might experience overly high cortisol levels, especially if they regularly experience anxiety or depression (since these states also increase cortisol levels).
And this may lead to increased irritability, poor mood, and trouble sleeping, which in turn can create a vicious cycle.
Higher Psychological Stress
Another point to consider is that fasting in and of itself is psychologically stressful too, not just physically stressful. You may experience increased hunger, strong cravings, and mental fatigue, especially if you try to fast for too long.
All of this further increases stress levels and may even increase brain inflammation, which can worsen mood over time.
Unhealthy Thought Patterns
Lastly, fasting may increase the risk of developing an obsessive or otherwise unhealthy relationship with food. If you already experience anxiety, depression, and other mental health issues, it is likely that you’re more prone to developing negative thought patterns in general.
Thus, when fasting, you may start to develop overly rigid and regimented thought patterns and habits regarding when you eat. And you may become overly critical if you don’t adhere to your prescribed pattern.
This obviously isn’t good for staying mentally well and at ease!
How to Implement Fasting for Mental Health
Overall, due to the potential drawbacks, I argue that most individuals with mental health problems shouldn’t undergo long fasting periods.
From what I’ve seen, most people can still implement some form of time-restricted feeding, but typically no more than 16 hours.
And, in fact, for most people with anxiety or depression, sticking to a simple 12 hours on/12 hours off schedule seems best, especially at the start. This is because, while research has shown benefits of fasting for anxiety, depression, and other mental issues, the overall picture is still unclear.
And importantly, they typically haven’t used actual clinical patients, so people with clinical depression and anxiety are likely more sensitive to the negative effects of fasting as opposed to those with just subclinical mental issues.
As a result, eating in this way still allows a nice gap of time (12 hours) for the body to clear out waste and repair itself. But at the same time, it’s not too long that it increases the risk of cortisol elevation, excess hunger, and negative psychological states.
How to Implement
To implement this best, it’s important to eat during the day and not too late at night.
I’ve seen many people do fasting where they skip breakfast and then eat all their meals later on in the day. But this isn’t best, especially if you have mental health problems!
Instead, eat mainly during the daylight hours, such as from 7am to 7pm; 8am to 8pm (you get the idea). This aligns with the body’s circadian rhythm and ensures you don’t disrupt sleep from eating too late at night.
Conclusion
Fasting can be beneficial for mental health. And even for those with clinical anxiety and depression, some form of time-restricted feeding seems generally positive.
However, there are potential drawbacks, especially if one starts getting into particularly longer fasts of 16+ hours. This includes increased stress, worsened sleep, fatigue, and irritability.
Now, if you don’t have clinical mental health issues but just suffer from occasional anxiety, stress, and low mood, it may be okay to try out longer fasting periods.
But for those with clinical anxiety, depression, insomnia, etc. it’s best to stick to roughly a 12-hour eating window and thus a 12-hour fasting window too. From there, you can see how it affects you and make any changes based on how you feel.
And if you need any help implementing a fasting period for your mental health; and/or are looking for other natural ways to improve mental health, please check out my mental health consultation services.
References
- Fasting Interventions for Stress, Anxiety and Depressive Symptoms: A Systematic Review and Meta-Analysis- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8624477/
- The Effect of Fasting on Human Metabolism and Psychological Health- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8754590/
