Whatever your view of his politics, when it comes to food, the Prime Minister’s self-discipline is remarkable. Apparently Rishi Sunak starts his week – every week – with a 36-hour fast: he stops eating at 5pm on Sunday and drinks only black tea, coffee or water until 5am on Tuesday.
Even though I’m a faster veteran, I’m impressed. Not so much the fact that he embraces fasting; There’s plenty of research showing that if you’re otherwise healthy, there’s a lot to be gained by giving your body an extended break from eating—and many people are doing this now.
But few of us have the willpower to deprive ourselves of food for as long as he does.
I’ve tried just about every form of fasting and I’ve found that it’s difficult to go more than 24 hours without eating. (I’m also not sure if this is the best way to reap the benefits of fasting, but more on that later.)
A few years ago I fasted for four days for a TV documentary. It was just water, sugar-free black tea and coffee, and a measly cup of soup with 25 calories a day.
I’ve tried pretty much every form of fasting and I’ve found it’s hard to go more than 24 hours without eating
Fasting helps improve blood sugar levels and can lower cholesterol levels and blood pressure
Rishi Sunak starts his week by abstaining from food for thirty-six hours, drinking only black tea, coffee or water between 5pm on Sunday and 5am on Tuesday.
It was tough, but health-wise effective: after four days I lost 3 pounds, a significant portion of which was fat. My blood sugar levels also dropped significantly, as did other biomarkers, such as insulin-like growth factor 1, which is linked to cancer.
Despite the benefits, I’m in no rush to do long-term fasting again. I wasn’t as hungry as I expected and didn’t feel faint, but I was distracted by an uncomfortable and out-of-place feeling. So hats off to Rishi for putting himself through a major fast every week.
In fact, you could be forgiven for thinking that Monday might not be the best day to ask Rishi to make crucial decisions about running the country when there’s a chance he might be consumed by hunger pangs.
But there is some evidence that fasting, if you get used to it, can improve focus. Professor Mark Mattson, a neuroscientist at Johns Hopkins School of Medicine in New York, told me that our ancestors faced periods without food, during which time they had to focus intensely on the best way to get the next meal.
The theory that the fasted state produces increased levels of concentration is one of the reasons why this really took off in the tech world a few years ago. That could be one of the reasons why Rishi does it.
People have been fasting for religious reasons for centuries, but more and more research supports its health benefits, showing that the metabolic changes that occur when you give your body a break from food can be beneficial.
Kiwifruit can boost your mood
Why not put a kiwi on your shopping list this week? Research from the University of Otago in New Zealand found that it can improve your mood, especially if you have low levels of vitamin C, which is known to have an impact on mental health.
For the study, published in the British Journal of Nutrition, 155 adults with low vitamin C levels were given a supplement, a placebo or two kiwifruit every day.
Although those who took the supplement experienced some improvement in their mood and sleep, those who ate kiwi experienced the biggest impact, with improvements in just four days. This may be because in addition to vitamin C, kiwi also contains melatonin, a hormone that helps to induce and maintain sleep.
It’s not just kiwi; Cold water swimming has recently been shown to reduce mood swings, irritability and hot flashes in menopausal and younger women.
So if you’re feeling down, maybe eat more kiwi and consider swimming in cold water when the weather is warmer.
A 2020 Harvard Medical School study found that it can improve the body’s defense against oxidative stress (damage caused to cells by factors such as smoking and pollution).
Fasting also helps improve blood sugar levels and can lower cholesterol levels and blood pressure.
It may also help brain function, with some studies suggesting it stimulates the growth of new cells in the hippocampus, a part of the brain linked to learning and memory. Most impressively, it reduces chronic inflammation, which is linked not only to conditions like arthritis, but also to many other age-related diseases, such as heart disease and dementia.
Last week, a study from the University of Cambridge found that when volunteers were allowed to eat just 500 calories per day for two consecutive days, the amount of arachidonic acid in their blood increased, which in turn helped reduce inflammation.
In addition to reducing inflammation, another benefit of fasting is that it gives your digestive system a break from food; this prompts your body to begin the important process of cellular ‘spring cleaning’, which breaks down and recycles cells.
Finally, fasting encourages your body to switch from burning sugar to burning fat for fuel – which is great news if you’re looking to lose excess weight. A review of studies published in the journal Nutrition Reviews in 2015 found that one day of fasting, once a week, for 12 to 24 weeks reduced body weight by as much as 9 percent.
But most fasting research has been on alternate-day fasting, intermittent fasting (like my 5:2 regimen) or time-restricted eating (TRE), where you eat within a set time frame – for example, you can start with a 14-hour ‘fast’ , and only eating in a ten hour window, then gradually increasing this to a 16 hour fast, and then maybe 18 hours.
And when it comes to fasting, you can have too much of a good thing. Rishi’s 36-hour fast is just too hard for most people. It is certainly not suitable if you are pregnant, breastfeeding, under the age of 18, have a chronic illness or a history of eating disorders – and speak to a GP first if you have diabetes.
The eminent aging expert, Professor Valter Longo, once told me: ‘Prolonged fasting is an extreme intervention. If done right, it can be very powerful in your favor. If done the wrong way, it can work very powerfully against you.”
There are of course many different ways to fast.
Go to a fasting clinic in Germany and you’ll probably consume about 200 calories a day in a comfortable environment. In Russia you get nothing but water, cold showers and exercise. But it doesn’t have to be that difficult to be effective.
If you are otherwise healthy, some form of fasting is a very good idea. And it’s great to know that you don’t have to use the full Rishi to reap the benefits.
We must be brave enough to call out bad behavior
Earlier this week I stood in a very long line, waiting patiently, along with hundreds of others, to go through passport control and enter France.
At one point I saw a few young men come straight to the front of the line. A few people were tutting, but only one woman was brave enough to bother them. But they ignored her and got away with it.
Michael Moseley was waiting at passport control to enter France when young men pushed through the queue
Unfortunately, this happens all too often. I was too far away to participate, but I’d like to think I would have supported that woman. And that’s important, according to a recent study from Bath University – because failing to speak up for the lonely voices of people confronted with bad behavior leads to bad behavior being normalized.
The research, published in the British Journal of Social Psychology, involved showing scenes of volunteers engaging in antisocial behavior – in some cases the people behaving badly were confronted and this was supported by other bystanders; in other cases the confrontation maker received no support. The volunteers were then asked what they thought. When there was no support for the confrontation, they assumed it meant the behavior they had just witnessed wasn’t that bad.
As researcher and behavioral scientist Anna Tirion has noted, “When no one speaks up, it undermines the social norms that protect against kindness and non-harm. Over time, people start to think that certain (antisocial) behavior does not matter.’ It takes courage to confront bad behavior, but she suggests ways to do it safely and how to support those who are willing to stand up and stand out.
“It depends on the situation,” says Anna Tirion. ‘If your face is visible to everyone, as in the Zoom call we simulated in one of our studies, simply nodding can be enough to send that supportive signal. Otherwise, a verbal statement of support such as ‘Yes, you are right’ would be sufficient.’
She adds, “If you are physically some distance from the confrontation, you may want to stand next to the confrontation before speaking so that your entire body language expresses that support — if you feel safe doing so.”
