I was pleased but not surprised to read that people on an intermittent fasting (IF) diet lost more weight over a year than those counting calories, perhaps because they found it easier to stick to. IF, in whatever form it’s done, is wonderfully straightforward.
In this case, participants ate very small amounts of simple food on three days a week and ate normally on four. They didn’t have the endless question of calorie content hanging over every meal for a year, and they could relax on their off days.
I was intrigued, though, to see that the fasters not only lost more weight but had healthier bodies overall. Their blood pressure, cholesterol and glucose levels all improved more than the dieters’ did. The scientists involved don’t say whether this was the corollary of greater weight loss or whether it was due to fasting’s known effects on cellular function. Either way, IF appears to have the edge on ordinary diets for fat loss and health.
I have been a fasting enthusiast for almost 13 years, not because I enjoy it, but because from the moment that I tried it, as a sceptic, it had the most dramatic effects. I was an early adopter. My concern wasn’t weight but failing health. It was 2011, 18 months before Michael Mosley published his instantly successful 5:2 diet, and I had an autoimmune illness that had become so debilitating that drugs had nothing left to offer.
Grim life-changing surgery was imminent when I happened to read that the world’s leading fasting researcher, Professor Valter Longo, had just proved that mice who were regularly fasted on water for three consecutive days completely rebuilt their immune systems.
Calorie deprivation forced the cells into autophagy, where they broke down and re-used all the damaged and dead material they could find, from malfunctioning stem cells to tumours and viruses. After three days of deprivation, the bone marrow generated new healthy stem cells to replace the old faulty ones, with transformative results.
Longo speculated that this research could be developed in the future to help humans with autoimmune conditions, and indeed all of us as we age into less efficient bodies. I couldn’t wait for the future.
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For almost three days I had nothing but water and herbal tea, thinking it was likely to be a waste of time. But on the fourth day I woke to find almost all my symptoms had vanished, and when I fasted again a couple of weeks later, the result was greater improvement still. Almost 20 years of high-dose steroids, immune-suppressant drugs and noxious intravenous infusions had done less to mitigate the illness than simply stopping food.
I have been an occasional faster ever since, just to keep the symptoms at bay. Since then, the science of fasting has leapt forward. In 2016 a Japanese scientist, Yoshinori Ohsumi, was awarded the Nobel prize for his groundbreaking discovery of how autophagy is triggered by starving cells. Longo’s fasting research became one of the main sources of the IF diets that have swept the world. He has continued to find new aspects of fasting’s effectiveness. Our bodies didn’t evolve to eat all the time. As Longo once said to me, eating without giving your body a break to recover is like driving a car with the accelerator down, and never stopping to give it a service. Fasting is that break for repair.
A couple of years after his autoimmune discovery, he made a key discovery in cancer treatment; that mice with breast cancer who were given chemotherapy greatly reduced its side-effects if they were fasted before, during and for 24 hours after chemo.
Again, the mechanisms of fasting were fascinating. When normal cells lose their food supply they essentially pull up a drawbridge, allowing very little to cross into the cell, so that the chemo drugs can’t poison every cell as they normally do.
Cancer cells, which are much less stably attached in the body, can’t create the same defence. They remain completely susceptible. So fasted mice could safely tolerate higher doses of chemo with less suffering.
Once again, this was a finding with remarkable implications for humans, given that a high proportion of cancer patients never finish their course of chemo because their bodies can’t endure it, and that about eight out of ten have lasting damage. Anything that can safely lessen chemo’s unwanted impacts is potentially of enormous significance.
As successive friends of mine had breast cancer, some of them wanted to try Longo’s protocol when I mentioned it. Everyone who did had far less serious symptoms in their fasted cycles than in their initial ones — for some, the difference was between a week or ten days of intense nausea, headaches, mouth ulcers and fatigue, and just 24 hours of feeling feeble.
When I had stage 3 bowel cancer and chemo four years ago, I decided I had better fast for every cycle too. This was my second shot at chemo and this particular one is notorious for its long-lasting damage, particularly on the nerves of the hands and feet.
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I knew people who had been devastated by its impact on their quality of life — a walker whose feet now felt they had gravel in them, a lifelong cellist who could no longer play, a mother who couldn’t do up her own or her children’s buttons because she had no fine co-ordination in her fingers.
It meant doing a five-day fast each time as my chemo ran over three, but after the first two cycles I couldn’t manage water only. On Longo’s advice, I ate only enough to keep the body in starvation mode — 300-500 calories a day, but crucially, with practically no carbohydrates and no protein. I was having almost no side-effects of any kind, just a little tingling in the fingers and toes. But on the fifth cycle or so I was at breaking point with deprivation and rebelled during it, eating a cheese sandwich and drinking coffee.
The consequences were almost instant. Within a couple of hours, I had nausea, terrible tastes in my mouth, painful feet, and hands that were suddenly so acutely sensitive to cold that I yelped when I tried to pick up a milk bottle or even a block of cheese. Every cell felt as if it were being poisoned, a horribly familiar sensation from the chemo of many years before. I went back to fasting, and by the next day all those sensations had receded again.
The only thing that is more remarkable than fasting’s effects is that the medical establishments and Britain’s Department of Health have remained so resolutely incurious and uninterested in any of it. Here we are, on the verge of understanding why an ancient protocol, practised by almost every religion, works so powerfully to improve our health.
It’s free, it’s simple and it’s transformative, and yet it’s not being officially researched, far less recommended. We need to know more about its power and its limitations; who can and who shouldn’t use it. Yet, medics, politicians and civil servants have their hands over their ears, leaving the rest of us to experiment with whatever we can read or find out ourselves.
