So far, the only intervention able to dramatically extend healthy life appears to be … fasting, otherwise known as Caloric Restriction (CR). Studies – on animals – suggest that regular fasting can extend healthy life by up to 30%. Susan recently wrote about her experience of fasting after trialling Professor Longo’s Longevity Diet, and we wrote about a shortened form of extended overnight fasting here. Many big pharma companies are now working on drugs able to mimic the effects of fasting (minus the gnawing hunger.)
A few drugs already do this – metformin (an old diabetes drug) and rapamycin, for example, are about to go into some form of clinical trial. Resveratrol in red wine also appears to have the same effect, although you’d have to drink an awful lot to get the effects and I suspect alcohol poisoning would outpace any longevity benefits. Various formulations of Resveratrol are also currently in clinical trial.
So that leaves fasting, which we know to be relatively safe, free and convenient. One of the best books I’ve ever read on health (The Obesity Code) is authored by Dr Jason Fung who, like Longo, Michael Mosley and many others, sings the praises of regular fasting.
For years I’ve come up with lists of reasons as to Why I Must Never Fast: my low blood pressure; my plummeting blood sugar levels; I’m underweight; I can’t concentrate when I’m hungry; I can’t sleep when I’m hungry; there’s food in the fridge that needs eating; it’s only proven in animals and I’m no animal; life is too damn short etc. etc.
But recently I’ve changed my mind. Why? Because a new study (ok, it’s mice again but bear with me) has found that a 24-hour fast appears to flick a metabolic switch that boosts the regeneration of stem cells in the gut. As we age our intestinal stem cells are less able to regenerate. And yet these stem cells are vital for fighting disease and maintaining healthy tissue.
“Fasting has many effects in the intestine which include boosting regeneration as well as potential uses in any type of ailment that impinges on the intestine, such as infections or cancers,” said MIT biologist, Omer Yilmaz.
When we fast, our cells stop burning carbohydrates and start burning fat. Which is why fasting has proved so effective for weight loss. But it appears that, in our intestines, something else is also triggered when our cells switch to burning fat. Our intestinal cell linings are typically renewed every five days, by our intestinal stem cells – the ‘heavy lifters’ of our guts. But fasting appears to speed up this process. Indeed the regenerative effect of fasting was double in mice that had fasted for as little as 24 hours, regardless of whether they were young or old. As ever, the scientists involved don’t fully know why or how this happens. And of course mice are not men (or women).
But, for older people with intestinal issues, an occasional 24-hour fast may be a simple way to give the intestines a boost. Scientists are already speculating how this research might help those in chemotherapy (a process that often damages intestinal cells), those with intestinal infections or gastrointestinal disorders.
I’m one of those. And for that reason, I’ve decided to do a fortnightly 24-hour fast. My trial has begun (I’ve done two separate 24-hour fasts) and it was far easier than I anticipated. No plummeting blood sugar levels. No brain fog. No dizzyingly low blood pressure. In fact – oddly – I felt absolutely fine. For 24 hours, that is. But if this latest research is right, why go hungry for any longer?
Will it work? I don’t know. But I’ll report back in due course. In the meantime you can read more at https://www.genengnews.com/gen-news-highlights/adult-stem-cells-get-a-boost-from-fasting/81255781
HORTA ON TOAST
When I broke my last 24-hour fast, this is what I ate. Horta is a Greek word for greens. In Greece at this time of year, horta is gathered from the wild but you can use any mix of green leaves you like. As it’s foraging time in my household, I used a base of spinach and kale, then stirred in handfuls of washed nettles and wild garlic, then topped the whole thing with chopped dandelion leaves and fresh herbs.
This is barely a recipe, but as I’m writing about fasting, it seemed appropriate. Add a poached egg, or scattered Feta cheese with toasted seeds. Then season and drizzle with a squirt of lemon juice and the best extra virgin olive oil you can stretch to.
- Toasted bread
- Green leaves (spinach, cavalo nero, chard, kale, nettles, cima di rapa, beet tops, dandelion leaves etc.)
- Any green leafy herbs (basil, parsley, lovage, mint, coriander, fennel, dill, chopped spring onions etc)
- Olive oil and lemon juice to serve
Wash the leaves, remove any woody stems and drop into boiling water for 1-2 minutes. Drain, blot excess water and roughly chop. You can steam your greens if you prefer but it’ll take a bit longer.
Toast your bread and drizzle with olive oil.
Season your horta (greens) generously, stir in the chopped herbs, pile onto toast and drizzle with olive oil and a squirt of lemon juice. Add a little chopped chili or chili flakes if you fancy.
Annabel
Lisa Sanders says
A really interesting post. I’ve read some things about the benefits of fasting, but have seen it defined in different ways. For example, from memory, only water/teas and infusions allowed/less than 200 calories. And for periods of 12 hours (i.e. overnight) or 24 hours or more. From your research, and your experience, what worked for you (I got the 24 hour bit!)? Also did you restrict ‘exercise’, e.g going for a run; or just go ahead with life as normal? Thanks!
Annabel Abbs says
Well, after reading Jason Fung I was relieved that a fast could include coffee and tea. So that’s what I drink, as well as water or a cup of miso soup if i’m hungry. The second time was much easier than the first, so I suspect it’s one of those things that gets easier. The beauty of a 24 hour fast (for me) is that I can eat an early (large!) supper, go to bed without feeling hungry, and the following morning do my usual exercise (yes, a run would be fine) and then push on through until I get to evening – and another early (large!) supper. It works for me, as I always cook for my family in the evening. But if you can cope going a little hungry in the evening you could start after lunch and go through to the following lunch? And yes, it’s only liquids. And my main advice is to keep busy and avoid being close to food! Let us know how you get on …
Lisa Sanders says
Hi Annabel,
Thanks so much for your reply. That’s very clear now, and something I’m sure I can manage (as long as I can avoid the fridge, which with three children can be a challenge!). I’ll have a go next week and let you know how I get on.
Annabel Abbs says
Good luck… much harder to do with children!
Lisa Sanders says
Absolutely right. Just made 40ish gingerbread people for a school thing tomorrow; but I held out (apart from half an arm, quality control).
I’m looking forward to soup later. But quite honestly it hasn’t been that difficult today. I’ve had a couple of cups each of tea, coffee and miso. It’s more the habitual pull of the fridge I need to curb, not the hunger pangs. I’m going to stick with it. Thanks for the post!
Annabel Abbs says
You’re welcome. BTW I try and ‘run’ the fridge down so, come fast day, there’s not much in it. Not so easy with kids though…
Debbie Cave says
The Monks in the 14th Century were certainly onto something. And in Primeval times too. After a kill, the Cavemen would often go for a few days with no food until the men returned with another stag or bore. Our bodies were never designed to eat as much as we have become accustomed to over the past half century or so. Intermittent fasting is a key discipline of a nutritional programme I am an Ambassador for and would be delighted to tell you more should you be interested. It is hugely effective in helping with not only weight loss, but also for athletes looking to turn lean fat to muscle and gain better energy, performance and muscle recovery. Email me – cavecom@btinternet.com
Annabel Abbs says
Intriguing … Thanks for the comment!