Six Facts on Fasting
It was unimaginable to me that I could possibly go a day without eating, let alone several. Yet, after adopting a Low Carb Healthy Fat lifestyle, I noticed that the pangs of hunger which would drive me to the fridge had somehow magically melted away, and I was no longer a slave to eating every few hours.
So what had happened – and is it a good idea to miss meals, or even a few days of meals (or more)?
Here are six things I’ve learnt about fasting over the last few years. Don’t miss point 6, it’s my “interesting fact” for the day.
- Fasting is easy if you are fat adapted, hard if you are not. Fat adapted means eating low carb for a few weeks and letting the body develop a better pathway for oxidising fat as a primary fuel source, especially using ketones for brain fuel. When you have a brain that is able to operate on ketones and can do so easily, then missing a meal (or several) is super easy. In my experience it’s even easier if you are busy, especially the compressed eating window (where you narrow the time you eat in a day to just a few hours).
- It’s a bigger step to move from a day to several days fasting. You do have your ups and downs, most of these are behavioural, especially if you have children. In my world, eating with my family is big deal and we have three boys; two teenagers. While we could leave them to their own devices for the time we’re fasting, that is probably negligent parenting. In reality they’d end up buying Burger King or similar for their evening meals, which is parental negligence. For me, preparing food for kids, while never eating anything myself is nowhere near fun. It’s not that I am hungry really, it’s just something biological about the preparation and smell of food that activates things that I am trying to avoid.
- Mental clarity is enhanced. At least that’s my experience. I find the days when I skip breakfast and eat later in the day are my most productive. So much for breakfast being the most important meal of the day. Three days into a fast and I’m generally firing on all cylinders and get my best work done.
- Sometimes my sleep is not as deep or as long, but I still feel OK. For me, this is generally the reason I end up breaking a therapeutic fast. By day 4 or so, I find that I am losing sleep quality and quantity. I like sleeping, so that’s a negative. I reckon the sympathetic nervous system is primed in a “I’m ready to go and find (hunt) food no matter what” evolutionary sense. I don’t think there is much research on this, but it’s certainly something I experience.
- You might age slower – the latest research into how and why we age identifies a pathway called mTOR (mammalian target of rapamycin) as a key controller of the energy production process in the cell. In their 2013 Nature paper, Johnson et al. show that reducing mTOR pathway activation slows ageing. A second pathway which has the opposite effect is through AMPK (AMP-activated protein kinase). AMPK keeps cells healthy through a self-maintenance program, and helps them die when they should die (programmed cell death). mTOR is anabolic (growth) and AMPK is catabolic (breakdown and repair).
We need both anabolic and catabolic states for health. But the problem is the growth (anabolic) phase ages us, and the modern high-carb diet never allows us to get back to the catabolic state. Fasting and LCHF allows you to reach that catabolic state again. Your body has the right signals to preserve and repair cells, and kill off the ones that are past their use-by-date. The high-carb diet drives constant growth signals that result in cell damage without taking stock and repairing the damage. This is ageing.
Johnson, SC, Rabinovitch, PS & Kaeberlein, M (2013). mTOR is a key modulator of ageing and age-related disease. Nature, 493, 338–345.
Fact 6: If you have enough body fat you can fast for a very long time. The world record for a supervised therapeutic fast is 382 days. It was set by a Scotsman in the 1960s. Here’s some interesting extracts from “Features of a successful therapeutic fast of 382 days’ duration”, published as a case report in the obscure Postgraduate Medical Journal (1973) 49, 203-209
“Patient A.B. aged 27 years, weighed on admission 456 lb (207kg). During the 382 days of his fast, vitamin supplements were given daily as’Multivite’, vitamin C and yeast for the first 10 months”
Results: Body weight loss
“During the 382 days of the fast, the patient’s weight decreased from 456 to 180 lb. Five years after undertaking the fast, Mr A.B.’s weight remains around 196 lb. “
In discussing the extremely low blood glucose levels…”Despite the hypoglycaemia the patient remained symptom-free, felt well and walked about normally.”
Last…“No faecal collections were made, but evacuation was in fact infrequent, therebeing 37-48 days between stools latterly.”
So there’s your interesting fact for the day! Fasting, despite the fact that a few years back I would have openly ridiculed people who fasted as fringe nutcases, if you haven’t fasted then it’s worth a crack and probably quite good for your brain and body. You’ll at least learn a thing or two about your own physiology while you are self-experimenting.