36 hour fasting for fat loss, cell healing and blood sugar control - could it be for you?

This week, for the first time since I did a sponsored 24 fast as a teenager, I did a long fast; 36 hours. Rather than delving too much into the details of the potential benefits of a long fast (stabilising blood sugars, appetite suppression, fat loss, cellular repair and growth), I'm sharing personal experience so you can decide whether or not it’s right for you.

I’ve been casually doing a 16:8 fast daily for several months, omitting the week leading up to my period when, according to Dr Mindy Pelz, the body needs more calories to support progesterone increase, and when the stress of a fast may lead to more cravings and anxiety (no thanks, got enough of those). 

I believe that the biggest challenge in fasting is in the mind - telling yourself stoires about why you shouldntor can't orwon't be able to do it. But doing regular 16 hour overnight fasts really helped pave the way (by the way, I generally stop eating around 6-7pm and start again around 11am the next day but if you’re worried, try starting at just a 12 then 14 hour fasting period and build up from there).

I was still worried about the 36 hours though. Worried about how I’d cope cognitively (I consciously planned my day to do my thinking work in the morning), physically (I ran a personal training session but didn’t join in with too much of it) and in terms of my mood (usually, I’m snappy and irritable if my blood sugar drops too quickly so I built in an emergency chocolate contingency plan, just in case).

So here was my day:

Awake 6.30, already my mind is focussing on the fact that I can’t have breakfast later. And then it dawns on me, I can’t have my flat white either - how will I cope without my morning coffee??

I normally start the day with hot water and lemon juice anyway, to set my sensitive gut up in the best possible way (highly recommend), and the usual busy morning getting the kids off to school stopped me from overthinking things too much.

9am fennel tea. The sweetness was good.

10am feeling a little hungry but gearing up for a PT session. PT was fine, I didn’t do much of the workout this time.

12 pm meet a friend for a walk into the village and a cuppa. I always resent spending money on a tea bag that costs 50p (happy to spend on a coffee) but alas, a green tea for me. My eyes lingered on the pastries and my nostrils enjoyed the aromas coming from the next table but I was distracted enough in conversation to not worry too much. Tummy rumbling minimal. Still able to focus surprisingly well.

1pm drink another green tea at home, anything to stop me thinking about food. Light housework and admin. Husband - who’s doing the fast with me - keeps talking about how hungry he is. I manage not to tell him to shut up.

2.30pm I’m starting to feel a little fuzzy headed but not actually hungry. Grateful for husband doing the school run and taking the kids to the park so I can potter and tidy, alone.

I suddenly notice a really strong smell of daffodils. I realise it’s coming from the flowers my kids gave me for mother’s day several days ago. My sense of smell is clearly really strong now. An evolutionary survival mechanism to help our genuinely hungry ancestors detect food.

4.30pm making the kids dinner feels a bit cruel to myself. In the fridge I see all my favourites, my sister’s home made coleslaw, fajita mix leftovers, grilled haloumi - oh oh ooooh! But again, the distraction of hungry, grumpy kids allows me to not dwell on it and once their dinner is on the table I take myself to another room…and wait for bed time.

5.30pm I need distraction but am wary of doing too much and don’t feel I have the concentration to read my book (plus I know my toddler will interrupt any minute). So I play a couple of board games with my youngest and wait for the evening. Wishing I could go to bed early so I can wake up and eat something.

Husband is talking about being hungry again. I smile. I realise I’m actually enjoying the process of challenging myself (and perhaps beating him), and proving that I can do hard things. Something I remind my kids of all the time (growth mindset).

Before starting this, I’d discussed with my husband my worries about a sudden drop in blood sugar, how I normally get super shaky and irritable, even confused and unable to make decisions. And we’d agreed I should eat some chocolate if that happens (a way out, a ‘cheat’ like in a computer game). But that’s not necessary so far. I drink lots of fizzy water with fresh lemon juice and this feels really good.

7.30pm time to head off to the AGM of my local climate action group. Thankfully, nobody brings biscuits. Conversations about larger problems than my self-inflicted hunger, such as ‘big water’ dumping sewage into our rivers, the ‘manosphere’, and how we build climate resilience in our community, rightly take centre stage in my brain.

Home and bed at 10. Still worried about how I’ll cope, will I sleep ok? I anticipate waking in the night starving and unable to get back to sleep (notice how so much of our mental struggles are entirely fictional, a future that hasn’t happened). And guess what? I slept really well, with a little help from a podcast. 

6am woken by husband, grrrr! Notice I’m not actually hungry and the overnight oats I prepared for myself last night, don’t appeal to me at all.

8am eat the overnight oats with blueberries, flax seed, creatine and collagen powders. Actually I didn’t even want it particularly but I had been unusually snappy with my 4 year old while making her breakfast so I felt maybe it was time to get some energy into me. The cup of earl grey with a drop of milk was most heavenly.

So there you have it. I anticipated serious cognitive decline, irritability and miserable hunger. But really I got none of that, certainly not for long. Instead my energy levels were stable, I didn't experience a strong earch for gin or chocolate at 4pm like I usually do, and there was definitely a deeper awareness of my whole experience throughout the day. The lack of food was like an anchor keeping me in the presnent moment.

So if you’re considering it firstly remember, if you have ever experienced disordered eating, have diabetes or other metabolic diseases, you must consult your doctor before starting any fast regime.

And then I’d say for a longer fast, choose a day when you’re not doing much but have some distractions to keep you going. Stop eating the night before (best to fuel yourself on a decent dinner) and during the next day perhaps meet with a friend, take a walk, do some light work or admin. And see how you feel.

Of course you’re not going to ‘see’ or even feel any long lasting changes after one fast. I’m aiming to bring this in monthly or even fortnightly to see if anything changes over time.

But the evidence shows us that longer fasts so help our very cells to heal, our blood sugar levels to stabilise and importantly for many of the women I work with, our body to burn through excess fat, especially around the belly. Worth a try in my view. And at the very least we get to experience a day when we're really noticing our own body and behaviours, and maybe there are some lessons to be learned just from that.

PS remember to sign up to the mailing list so you never miss a blog post. Head to the home page and wait for the pop up.