Amber Tries: 48 hours fast

 A couple of years ago, I tried a form of intermittent fasting: the inaccurately labelled "Wolverine Diet". I say it's inaccurately labelled because the 16:8 fast (as it is also known) is not strictly a diet: it does not dictate what food you can and cannot eat. You could be on a vegan, vegetarian, gluten-free, kosher, halal...or any other sort of diet while practicing intermittent fasting. It is more accurately described as an eating schedule whereby you eat during an 8 hour window and consume no calories for the remaining 16 hours of the day. Thankfully, sleeping counts as part of the 16 hours. 

Since my post on the 16:8 fast, I have intermittent-fasted intermittently (ha!). The reason I found daily intermittent fasting difficult to keep up is the fact that it didn't fit in with my lifestyle. During the week, my profession ensured long hours in the office and the ever-present temptation of stress-eating; on the weekends I found 16:8 really messed with my social life. As an amateur food blogger and gourmet who socialises with restaurant meals, daily intermittent fasting was incompatible with what brings me happiness. 

That brings us to this year. I don't suppose anybody needs reminding what is currently happening in the world. Since March, I have worked from home and put my social life on hold for the most part. The enforced decrease in the pace of life means I finally had the chance to attempt a longer fast. 

A 48 hour fast is not quite in the prolonged-fasting category. That title is usually reserved for a fast lasting 72+ hours. Therefore, a 48 hour fast is still technically intermittent fasting, but it is necessarily practised a lot less frequently than other forms of intermittent fasting. 

When I first considered going on a longer fast, the first thing that popped into my mind was: isn't it unhealthy? I had grown up being taught to eat 3 solid meals a day with snacks in between to keep my blood sugar in a steady state, so it took me a lot of reading to come round to the 16:8 fast. The 24 hour fast seemed to take intermittent fasting to a whole new level. Won't I go into "starvation mode", where my body thinks I am in the midst of a famine and tries to hold onto all the fat it has? 

The current state of research suggests that instead of being inherently unhealthy, fasting has a number of benefits. For instance, one of the studied benefit is the effect of fasting on insulin resistance. The jury on whether fasting really is as beneficial as preliminary studies have found is of course still out; and needless to say, there are risks associated with intermittent fasting, particularly if you have certain underlying conditions. 

The bottom line is, after the reading I have done, I am personally comfortable that intermittent fasting won't harm me - but that doesn't mean it is for everyone. 

As for whether my body would go into "starvation mode", for a healthy adult, 48 hours (or even 72 hours) really isn't long enough for the body to go into "starvation mode". After around 24 hours of fasting, our bodies switch into steady fat-burning mode. Our glycogen stores are significantly depleted, so the process of lipolysis (the breaking down of fat) kicks into gear, and our bodies produce and use ketone bodies for energy. I can't tell you what length of fasting is required to get the body into "starvation mode" - I never looked into that because I can safely promise that I will never voluntarily fast for longer than 72 hours. 

So if I am personally comfortable with the risk/benefit of a 48 hour fast, what took me until lockdown to test it out? The answer: the fear that I would be so hungry that I'd be lightheaded and not able to do my job or go about my day effectively. 

Well, I have now done the 48 hour fast a couple of times, and here is my report. My personal pattern generally goes something like this: 

0 - 16 hours (sleep included)

Having previously 16:8-fasted, 16 hours really isn't much of a challenge to me. Even when  I'm not actively trying to 16:8-fast, I am just the kind of person who values an extra half hour of sleep above breakfast. Sometimes, I have a busy morning and simply end up not eating for 16 hours inadvertently, so my body is pretty used to that length of no food. That's not to say I don't have hunger sensations, but they are usually quite mild akin to a polite nudge. 

16-24 hours 

At this stage of the fast, I begin to feel quite hungry, or what might colloquially be described as "I'm starving!". The hunger cues are getting increasingly difficult to ignore, and I start to have vivid food thoughts about everything that I enjoy eating. There is no particular preference for high energy food, just a general longing for food. I find myself thinking about the food I had  in the days before I went on the fast. 

24 hours - 30 hours

This is the toughest period for me. The physical sensation of hunger peaks, and I can become a little shakey. My heart rate increases, and I can feel weak. On one attempt, I started to get a bit of a headache around this stage, so I immediately dropped the fast. I don't believe in pushing through if one's feeling terrible; however if it's a manageable kind of discomfort, I sit with it and push through. I now try to time my fast so this period coincides with sleeping. That does make the fast easier, but that also means a less-than-ideal night of sleep. 

36 hours + 

I feel amazing after 36 hours: the hunger signals are suppressed, and the most incredible thing is the mental clarity and burst of energy I get after fasting for this many hours. I am alert, clear-headed, and super-productive. It's like I bio-hacked myself to perform at my optimum. On the latest 48 hour fasting attempt, I timed it so that I was doing a particularly challenging piece of work during this peak-performance period, and it worked a treat. One way I explain this phenomenon to myself is that humanity would have died out millennia ago if we all became completely useless after not being able to find food for a day or two. 

So, would I recommend a 48 hour fast to everyone? Absolutely not. My attempts at this fast brought back memories of the 40 hour famine: remember when that was a thing at school?  I know it's for a good cause, but now that I have experienced it myself, I think it was quite irresponsible to encourage teenagers to do it, particularly when we consider how vulnerable teenagers can be to eating disorders. So to start, I categorically would not recommend a 48 hour fast for non-adults. It follows that I also wouldn't recommend it to anyone with underlying health conditions, including mental health conditions such as anorexia and bulimia. 

As for healthy adults, I suppose it is something that you might try as an interesting experiment, if you want. Apart from the mental boost that allows me to "cheat" my way to an ultra-productive work day, the reason I will continue to fast for 48 hours every few months is because I find that it resets my palette. 

After a few weeks of eating rich food, I find that I get a taste for them and start to really crave them. A 48 hour fast resets that craving. The 36 hours mark is also when I notice a shift in my food-related thoughts: instead of just wanting the kind of food I had been consuming immediately before the fast, I start to crave fresh produce and nutritious food.  I have vivid recollection of day-dreaming about baked salmon with greens, and apple slices with a smear of peanut butter. In particular, sugar craving noticeably  decreases after a fast: I can't quite stomach the idea of milk chocolate for many days after completing a fast. 

Having said that, there are many risks associated with fasting. For example, if you have a sensitive digestive system, fasting can really mess with that. Those who suffer from heartburn might really feel it. Of course, there are also risks associated with dehydration and electrolyte imbalance if a fast isn't done properly. 

So, take this review for the entertainment it is meant to be; and if you decide to give 48 hours fasting a go, please, please please do some research on how to safely fast, and maybe talk to your doctor, particularly if you have conditions which might increase the risks associated with fasting for you.