The effect of Intermittent Fasting on the brain, or Fixing My Head

This is the written version of my speech on Intermittent Fasting I prepared for my Toastmasters Club.

I know it is hard to see it when I am up here- at my most animated, full of energy and nerves, but I suffer from depression- and have done so for the vast majority of my adult life. In my last speech- and Verity would have heard it at the Westlake club- I opened up about my mental health, with the aim of de-stigmatising depression- and found doing so gave me such a sense of relief, of total acceptance of where I am mentally, but also- most importantly- a huge amount of hope that I will be able to improve on the status quo.  That the traditional fixes that I have been relying on up until now- i.e. medication, exercise, healthy eating may not be the only avenues worth exploring.

Today, I thought I would share a recent- and in my opinion- potentially completely life-changing practice I am experimenting with-

Intermittent Fasting

Yes, I see your eyes rolling- you are thinking oh golly, what an anti-climax!  All we need is another speech about another new-fangled diet!  SIGH!

But wait. Hear me out.  I am not really interested in fasting for weight loss.  Although I do believe that it does work for that.

What I am wanting to share with you today, is the potentially very important effect fasting can have on the brain. More specifically, the effect fasting is having on MY BRAIN.

I am going to firstly run you through WHY intermittent fasting could be good for the brain- the science bit; and then touch on HOW to fast- or at least, the fasting method that is working for me.

WHY fast?  It makes a lot of sense, in terms of our evolution, to assume that our ancestors would have experienced hunger a lot more frequently that we do nowadays.  No fridge, no shops, no conveniences like a toaster would have meant you would probably have aimed to have one proper meal a day.  Perhaps eating as regularly as we do nowadays is not quite what our bodies were designed for.

I stumbled on a youtube video of Prof Mark Mattson, where he is advocating intermittent fasting as an extremely effective enhancer of brain capacity, performance and probably most important for me at this stage- its positive impact on mental health issues.  He looks specifically at the positive effect it has on degenerative conditions, such as Alzheimers and Parkinsons.

But I am wanting to take this a step further today, and suggest that- certainly in my case- I am experiencing a marked reduction in symptoms of depression intermittent fasting.

What happens in the body, when you fast, is that all the glucose supplies that are stored in the liver and blood eventually become depleted and the body then switches to the burning of ketone bodies.  This is very desirable for weight loss, because we are essentially tapping into our fat stores and burning that stored energy.  But what is the impact on the brain?

This is where it gets interesting.  Prof Mark Mattson suggests that perhaps ketosis is for the brain what exercise is for the muscles- in other words, it triggers neuronal repair and growth.  He has been able to show in rats that intermittent fasting results in brain stem cells forming new nerve cells- this is known as neurogenisis- in the hippocampus of the brain.

Interestingly, the hippocampus is the area of the brain associated with learning and memory, as well as mood and emotion.  It is the part of the brain that a brain scan will show the first signs of damage from diseases such as Alzheimers- where memory loss is the first indication of the disease.  Another effect of Intermittent Fasting that has been noticed in the hippocampus, is that it increases the levels of what is known as brain-derived neurotrophic factor, or BDNF.  BDNF is best described as FERTILISER for neurogenisis.  Depression is strongly linked with low levels of BDNF in the brain.  So, it seems logical that the effect I am feeling on my mood since I have started Intermittent Fasting a few times a week, could well be as a result of the improved levels of BDNF in my brain.


In the wild, you can imagine that this mechanism was very useful.  Picture Cam the Cavewoman.  If I have not eaten for a while, being more alert, more aware with enhanced cognitive abilities triggered by ketosis, would make me more likely to have a successful hunt, or develop a new way of digging for roots, or doing whatever it takes to get my next meal.


So now the HOW of intermittent fasting.  The 16/8 method I am playing with, means, essentially, that on most days, I skip breakfast and only eat at about 1pm.  By doing this I am “fasting” for 16 out of 24 hours and only eating within an 8 hour window each day.  I also believe in eating healthy, real foods, but have always been fairly good with that- I don’t have a very sweet tooth- so that has not changed.  Those are the – very simple- mechanics of the “diet”.  I often exercise in that fasting time period, and I don’t restrict my fluids at all- drinking water, tea and coffee, but with very little milk.

In conclusion, Intermittent fasting is not new.  People have been fasting for mental clarity, spiritual enlightenment or simply because they hadn’t had a successful hunt since the dawn of human existence.  It seems to me that perhaps  my brain- and possibly yours- functions far better if it has to use ketones as fuel from time to time- thereby stimulating increased levels of BDNF, that brain fertilizer and creating new nerve cells in the important hippocampus section of the brain.

Thank you.

The very act of eating can be exhausting; it takes a lot of energy to digest food. When the body is freed from that chore, it naturally feels lighter and much more vibrant. ~Allan Cott

I fast for greater physical and mental efficiency. ~Plato







I am extremely relieved to report that I am feeling a LOT better now. The withdrawal effects coming off the anti-depressents were truly dreadful- it felt like I was living in some kind of horrible, alternative reality- but they have subsided now.

So much has been happening, I thought it would be best to list things:

  • We have new addition to the family- a ridgeback puppy.  His name is Ernest and he is simultaneously the cutest creature on the planet and the most hectic.  We got him because he is one of the best kinds of dogs to run with and will make running in the forest and greenbelts a lot safer for me. He will also add to our security because ridgebacks are fairly intimidating, large breeds.  It is a long-term project, though, because Ernest will not be able to run with me until he is over a year old, without the risk of getting terrible arthritis later.  This means that at the moment, I need to walk the puppy and Benji AND run on separate occasions, which makes for lots of time outside, which is not a bad thing!
  • I am doing a lovely parenting course, called Roots and Wings.  I love the other moms doing the course and feel excited that some significant shifts will be made in our family as a result of the course.
  • I have done 2 Toastmasters speeches on Intermittent Fasting and want to post a detailed post on this practice, which really seems to be helping me.
  • We had the most incredible holiday over the long weekend at the end of April.  I can highly recommend a visit to Victoria Falls and this will definitely be a full blog post for another day.
  • I joined a #100gratefuldays challenge, where I am posting a pic each day and writing about what happened on that day that sparked gratitude.  It is a powerful practice that keeps one focused on finding those special moments throughout the day.

It feels like I am almost managing my depression and anxiety without medication, but I am not under any illusion that I am healed.  For example, I am struggling with feelings of victimisation and I have to remind myself all the time that I am the master of my own destiny and not a victim of circumstances.  That, for example, I chose to get a puppy and getting up in the night because of him is a consequence of my own decision.  A decision I do not regret, especially when snuggling him and breathing in all his precious puppiness!  Negative thoughts are present almost constantly, even as I search for my grateful moments and enjoy so much of my day!  The word “battle”, when used referring to depression is a truly apt one.  I battle ALL THE TIME.  But I don’t think I am losing the battle.  I am exhausted by it, but I feel I am making progress.

My hope is that my brain will adjust and strengthen in time and things that “push me over the edge” right now, will no longer do that and my capacity for stress, anxiety and anger triggers will improve.  Please, please, please let it be so.

Time flies!

I know I haven’t posted an update for a while, but have got a big shock to see that my last post was in March! So much for regular blog posts!

On the medication side, I have taken the plunge and been gradually weaning myself off my anti-depressant. This had been going fairly well- it was easy to go back to the standard dose I had been on prior to doubling it; it was fine- in fact, really good- to halve that dose and be on half a tablet per day.

BUT, what has been really awful, has been quitting them altogether (which I did almost 2 weeks ago). Googling my dreadful symptoms, it seems I have experienced EVERY SINGLE symptom of antidepressent withdrawal syndrome!

Symptoms of antidepressant withdrawal are sometimes called antidepressant discontinuation syndrome and typically last for a few weeks. Certain antidepressants are more likely to cause withdrawal symptoms than others.

Quitting an antidepressant suddenly may cause symptoms within a day or two, such as:

Insomnia or vivid dreams
Flu-like symptoms, including achy muscles and chills
Electric shock sensations
Return of depression symptoms

The most scary one is the electric shock sensations- that occur inside my head. I think they are becoming less frequent now, but, boy, has it been rough. I have really felt like I am teetering on the edge of insanity.

I guess, the truth of the matter is, I think I have done the wrong thing.  I don’t think I can cope without my meds.  And that makes me really sad.  But seeing as I have come this far, I should probably at least hold out until after all the dreadful side-effects of stopping them have ceased.  If I have the strength!





An admission- I am a fan of Kate!

I know it is silly.  But I can’t help it.  I am a huge fan of Kate Middleton.

I loved how she wasn’t afraid to show her tummy to the media directly after the birth of Prince George.

I think she does an excellent job in creating an elegant, royal image, although I think sometimes she errs slightly too much to the conservative side.  But that is definitely preferable to being too influenced by transitory trends.

But, most importantly, I love the work she and Prince William are doing in the promotion and de-stigmatising of mental health issues.

Here is an article relating to her recent speech.  And below is a quote from her speech.  Well said, Kate!



Update on medication (again!)

I have not been happy with my “doubling the dose” of my antidepressant.  Aside from that initial boost to serotonin levels, all I have noticed subsequently are the side effects.  Namely, dizziness, tiredness, headaches and, worst of all, a “drugged out”, unfeeling sense of distance from reality.  I have given the trial a reasonable length of time to come right and it just hasn’t.  Certainly not how I choose to live.

So, this morning I went down to my previous dose and I will have to see what impact that has on me.  I did a bit of googling- as one does-  on reducing the dose, and it is recommended to drop by 25% per week.  I have just halved it straight away, so I will probably feel a bit weird, but I am sure I will be able to push on through.  Of course, I should have consulted with my doctor before doing this.  But I think my logic is sound.  I have definitely not had a boost in my mood- the bigger bath-plug that my antidepressant is supposed to be for my serotonin levels has not worked at plugging that hole.

At the same time I have been reading about all the benefits that intermittent fasting can have on the brain.  The specific talk I watched (from a Toastmasters perspective, I must apologise for the far-from-riveting way this work is presented) is on this link and the talk is specifically referring to the preventative effect fasting has on the development of alzheimers and dementia.  In my own life, I have definitely noticed that I feel sharper, more mentally alert and yes, even happier, when I get into what I suspect is ketosis, or a fat-burning state.

Now, of course, I am toying with coming off the medication completely.  Given that my life is relatively simple and stress-free right now, this may be a good time to try this.  And, of course, I would love to be free of medication.  I have this constantly suppressed wish to be able to function free of medication.  It is suppressed because I know each time I have tried this in the past, I have turned into a sobbing, irrational loony who thinks the world is evil and everyone and everything is out to get me.  My doctor always tells me that there is no shame in being on medication for life if one has chronic depression.  I get the logic.  But the wish is there.

Should I try it once more?  Dare I?!

Another update on medication

I am now really not sure that doubling my dose of antidepressants has helped.

I have certainly noticed some undesirable side effects (which I am sure will subside), like a funny head-ache, a  tendency to feel like  a completely unemotional zombie, rather than a person, and a habit of staring into space blankly (!), but I can’t really say I am feeling more positive than I did before.

It was almost like I had an initial euphoric feeling to which I have now adjusted.  So disappointing!    I will carry on taking the higher dosage, but I am not nearly as hopeful about the outcome as I was before.

It wasn’t ever going to be as easy as just popping a pill, right?!

Postnatal Depression and Me

Matthew, my eldest, was born in London.  Part of the many pamphlets and flyers and discussions that happened in the NCT group I belonged to during my pregnancy, was a fairly comprehensive warning about the prevalence of Postnatal Depression.

At that stage, I was not on any medication for depression.  In fact, I was rather proud of how well I was coping mentally while living in the UK.

So many aspects could have triggered depression- what with the dark, cold, long winters (in comparison to a South African winter, at least!), being so far from family (aside from Pete!), a tough work environment and a lengthy commute.  Admittedly, I can’t say I was completely relaxed and loving my time there- I was in survival mode and pleased to be coping, but life was hard.

I found comfort in being one of the “worker ants”, who travelled along with all the other “ants” to our places of work and then home again each day.  Lining up to swipe our Oyster cards one by one, ride the escalators choosing to either keep left and stay on a step, or step down the escalator on the right side.  The social conformity was comforting.  I enjoyed the fact that the vast majority of the population were middle class, like me.  Being middle class in South Africa comes with guilt I felt free of while in the UK.  I found it reassuring to be living in a country with first-world problems- which seemed so much more interesting than the more fundamental problems  we were facing (and still face) in South  Africa.

I felt very aware that having my baby, might well trigger postnatal depression in me. I had already been treated for depression previously, which made my chances of getting PND very high.

Certainly, the nightmare birth, complications afterwards with severe mastitis, a very hungry baby boy who was almost colicky could have pushed me over that precipice into depression, but- oddly enough- they didn’t.

I was on the lookout for the signs, but they simply didn’t come.

What I suspect may have been the main reason depression was kept at bay during this time, was that amazing hormone released while breastfeeding called oxytocin.  Oxytocin-also known as the love hormone- is responsible for that incredibly strong feeling of connection and love a mom feels for her baby, but most importantly for this article, is that it is a powerful antidepressant.

I was also lucky enough to be one of those people whose body “bounces” back into shape right after the birth.  My body just became a milk-producing machine, at the cost of all the fat I had accumulated during pregnancy.  ALL my baby-weight was simply sucked out of me.  It is as simple as that and very quick.  I know that is not the case for everyone, but that was my experience.  And I am sure snapping back into shape also helped with my mood!

The years when I had one- and then quite quickly two- babies to look after, were very happy ones for me.  I felt fulfilled; I had such an obvious and important purpose to look after and nurture these vulnerable and innocent babies; I felt lucky to be able to be at home with them and I was able to see just getting through each day as an achievement.

My experience does not take away from the fact that PND is very common (up to 30% of mothers suffer with it) and simply terrifying to deal with in what is already an incredibly challenging time.  If you suspect you have PND, know you are not alone and please get help.  Here is a link to find out more about the condition and navigating from there will get you in touch with people who can assist.  Here is another link to a very powerful article about one woman’s experience of this condition.

A quick update on medication

I realised I had nothing to lose by increasing my dose of my antidepressant (thanks, Pete!).  Except, of course, the little dream of being able to move beyond needing medication one day.  In my head, I have accepted that I need to be medicated for the rest of my life, but in my heart I wish this wasn’t the case.  And increasing the dose is a new acknowledgement of a chronic problem.


Serotonin down the plug hole
Serotonin down the plug hole

On the other hand, it is so silly to fight the fact that there is a chemical imbalance in my brain (a lack of serotonin) which medication can fix.  And if, as my doctor explained here, the plug is just not quite big enough to be keeping the serotonin levels optimal in the bath that is my brain, how ridiculous not to use a bigger plug!


So, I started with a double dose yesterday, anticipating some side effects, but hoping that the side effects would be minimal because my system is so used to this medication.

I didn’t notice any change yesterday.  No nasty side effects, no impact on mood.  But today has been a little different!

I am feeling rather good.  Admittedly, the day has had a good structure to it so far.  I started it with a pleasant run with my running friend.  I then managed to shower quickly, plan my shopping list and be at the shops as they opened at 9.  This meant the store was well-stocked and nice and quiet.

And you see, I am not sure I would have appreciated this as much as I did, if I hadn’t been feeling better.  Early days, but I am rather excited!

A visit to the doctor

I have been taking standard SSRI’s (Selective Serotonin Re-uptake Inhibitors) for many years now.  I would estimate that I have been on various antidepressants almost continuously for at least the past 8 years.

My medication of choice has been predominantly Prozac generics and, more recently, Zoloft generics (better with anxiety, as I understand it).  I have tried a number of others that did not work for me (all those dreaded side-effects!) over the years.

I made an appointment to see my doctor last week, because I was wondering about a few things.

  • Firstly, there has been quite a bit in the news (articles such as this) suggesting that having low levels of Vitamin D have been linked with depression, lack of energy and more.  Living in South Africa, up until these kind of articles have been doing the rounds, one always assumed that our Vitamin D levels would be fine because of all our sunshine.  But the articles, plus the fact that I definitely struggle with my mood during the winter months made me think I would like to have my Vitamin D levels checked.
  • Then, I also thought I should just let him know that I am struggling mentally at present and see what he advised.
  • I have also been getting very light-headed when getting up (even just from sitting down, and not necessarily getting up that fast) and I wondered if this was cause for concern.
  • Finally, it is never a bad thing to have blood pressure, heart rate and cholesterol levels checked, so off I went.


My doctor took the bloods (which I absolutely hate- for some reason my veins are very hard to locate!), he looked at my blood pressure (perfectly normal, so low blood pressure is not the explanation for the light-headedness); commented that I was very fit (with a very low resting heart rate) and then proceeded to reassure me that being on antidepressants for long periods of time is completely fine- it  is, in his opinion, silly and unnecessary to aim to come off them, particularly in cases like mine where there is such a strong genetic predisposition to chronic depression.

Using the analogy of the brain being a bath, and the pill being the plug (to stop the serotonin- or water- from leaking out and being wasted), he advised doubling my dose of Talomil from 20mg to 40mg.  He explained that the only way of gauging the size of the plug hole was to increase the size of the plug until my mood was more in the normal range.

OK, I get that.  And in reality, if anything, I need MORE rather than less medical intervention at the moment.  I am feeling blue.

He gave me a new script and said he would let me know the results of the blood tests in a few days.  I decided to wait for the Vitamin D results before increasing my dose of medication.  The thinking being if my vitamin D levels were low, I would prefer to work on supplementing that than increasing my medication.

BUT, the Vitamin D results came back at normal levels.  My cholesterol is also normal. I am now having an internal debate.  Do I try a double dose of Talomil?  Is that the right thing to do?

The impact of elevated body temperature on depression

There is something that happens to me from time to time.  OK, admittedly, this happens to everyone.

I get sick.

As an adult, my illnesses have never been serious- mostly just viral infections that run their course- with all the snot, sore throat, sore head, coughs, sneezes, shivering and aching that are associated with your average cold or flu.

Quite often- usually towards the end of an illness- I get an incredible boost in my mood.  I feel creative, full of laughter, silly, and just plain HAPPY.  Which is just the most fantastic feeling for a person living with depression to feel!  I have thought previously that this must be the something that I feel as I turn the corner and am on the road to recovery.  A celebration of being alive, if you will. An anticipatory rejoicing in the realisation that normal life will resume soon.

BUT, the last time I was ill and felt this- I had a “lightbulb” moment and realised that there may be a link between my having had a fever (raised temperature) owing to my body’s fighting of the virus and my elated feelings.  I thought back to other times this had happened.  It seemed like it could well be the case that in each instance I had experienced this feeling of elation I had had a fever.

So I googled it, as one does.

Google led me to a relatively recent (admittedly small) study by a Dr Raison of the University of Wisconsin-Madison, where he has actually tested my theory out.  In the study, he recruited people that were moderately to severely depressed and then elevated their body temperature and found that this reduced the depression score in 60% of cases, with 40% of the cases no longer even registering as depressed.  In addition, the effect of the treatment lasted for up to 6 weeks afterwards.

I was so excited that I emailed Dr Raison AND HE REPLIED!

See our communications below:

From: Charles Raison <>

Date: Fri, Aug 5, 2016 at 3:06 PM
Subject: Re: Found your study on raising body temp to help with depression so interesting!
To: Cam Shackleton

Thanks for this email Cam. You’d be interested to know that I had a similar experience many years ago–I was pretty depressed and then got the flu with big fever and had a profound and rapid lifting of my mood that persisted once I got well. That experience played no small role in leading me into my current work.

We will be publishing another study in next 6-9 months showing that the immune system is linked to the antidepressant effect of hyperthermia, which also fits your experience.

All the best

Chuck Raison


From: Cam Shackleton

Sent: Friday, August 5, 2016 1:07 AM
To: Charles Raison
Subject: Found your study on raising body temp to help with depression so interesting!


Dear Dr Raison

I suffer with depression and I currently have a viral infection, with a mild fever.  I have noticed this before- and it is definitely the case right now- that my feelings of depression are absent! It feels fantastic! Of course, the headache, snotty nose, cough, etc are not ideal, but the joy/excitement/sense of being alive that I am feeling compensate for that quite considerably!

I just googled the effect I am experiencing this morning- and found your study. I really think this may be a potentially huge breakthrough and just want to encourage you with this!

Kind regards
Cam Shackleton
Cape Town, South Africa


Here are the links to some articles emanating from his research.

It makes me think that perhaps heated yoga, saunas, hot springs and the like may be very good for me (and others like me).  It may even explain some of why running helps me so much.  It gives me hope that there are alternative treatments I may not yet have discovered.

Please tell me I am not the only one to have experienced this?!