How healthy is Rishi Sunak’s ‘Monk fast’ diet
With his lean, wiry frame, Rishi Sunak was already known for his vigorous cycling workouts to keep him fit while he also has spoken in the past about the importance of fasting in his Hindu religion.
But now friends have revealed the full extent of his dedication to food abstinence – a weekly fasting regime known as the monk fast.
This sees him fasting for 36 hours at the beginning of each week – from 5pm on Sunday until 5am on Tuesday morning – during which he consumes only water and other zero-calorie drinks including black coffee and tea.
This routine is at the tougher end of a spectrum of fasting practices known as ‘intermittent fasting’, or IF.
This also includes time-restricted eating on a daily basis – typically involving a gap of somewhere between 12 and 16 hours between dinner and the next day’s breakfast, or any other way of squeezing all calorie consumption for the day into an 8 to 12 hour window.
Other methods include eating normally five days a week and restricting calories on the remaining two days.
But do these diets actually work?
Research looking specifically at monk fasting is thin on the ground but there is a growing, albeit early stage, body of research looking at the benefits of intermittent fasting more generally.
Of the research there is, a 2019 study by the University of Graz in Austria, published in the journal Cell Metabolism, is probably the most relevant to the monk fast.
This looked at a form of ‘Alternate Day Fasting’ (which can take several forms) in which 60 healthy participants alternated not eating for 36 hours with 12 hours of eating as much as they wanted, for four weeks.
This particular fasting routine is similar to the Monk fast but more intense because the 36-hour fast happens every other day rather than once a week.
But the findings of this study – the largest to look at alternate day fasting – are still highly instructive and they suggest there could be considerable benefit to the Prime Minister’s fasting routine.
The study found that the fasting regime:
- Reduced belly fat and overall weight, with body weight falling by 4.5 per cent, on average, over four weeks and an improved fat-to-lean ratio
- Lowered cholesterol levels
- Increased ketone bodies (produced by burning fat), even on non-fasting days, which are known to improve health, for example by reducing oxidative stress (which can cause damage to organs and tissues)
“We show that 4 weeks of strict alternate day fasting (ADF) improved markers of general health in healthy, middle-aged humans while causing a 37 per cent calorie reduction on average,” said study author Professor Frank Madeo, of the University of Graz in Austria.
“It improved cardiovascular markers, reduced fat mass (particularly the trunk fat) and improving the fat-to-lean ratio – and no adverse effects occurred even after more than 6 months.”
But despite the benefits of 36 hour fasting, Professor Madeo and others point out that this level of food abstinence is quite intense and so should be monitored closely – with more research needed to more fully determine the risks, as well as the benefits, of this level of fasting.
Given that Mr Sunak only does a 36 hour fast once a week – rather than several times – his regime is less intense, but even so, experts advise that people fasting for any length of time, especially on a regular basis, would still be well advised to exercise caution.
“It is important to consult a doctor before any harsh dietary regime is undertaken,” said Professor Madeo.
“We advise people not to fast if they have a viral infection, because the immune system probably requires immediate energy to fight viruses. And even healthy adults should not perform ADF without consultation by clinicians to rule out adverse effects due to critical medical conditions.
“Importantly, a wholesome and balanced diet is likely crucial to foster the beneficial effects caused by ADF. Thus, appreciable clinical support and a generally healthy lifestyle should be considered before starting.”
Professor Madeo’s study is not the only one to show the benefits of IF, however.
“There are many versions of what are called intermittent fasting. Alternative day (AD) fasting, time-restricted eating such an 8 hour eating window and 16hr fast or a 12 hour eating window and 12 hour fast. Most of these versions have been shown to have health benefits. Our paper shows both extended median and maximum lifespan [from fasting],” Professor Joseph Takahashi, at the University of Texas Southwestern Medical Center, who led a key study into IF, told i previously.
His study, published in the journal, Science, found that the benefits of cutting overall calorie consumption could be magnified by eating at the right time.
“Fasting alone – without calorie reduction – is beneficial,” Professor Takahashi said. “You should fast during your inactive phase of the day. A 12 hour fast is the minimum and some people think that 14 or 16 hours is better.”
Meanwhile, fasting for 12 to 14 hours a day can reduce insulin levels and help some people lose weight, according to a study by the University of Illinois, Chicago.
“These findings suggest that 8 hour time restricted feeding produces weight loss. It may also offer clinical benefits by reducing blood pressure,” according to the study, published in the journal Nutrition and Healthy Aging.
Fasting also gives our 100 trillion gut bacteria a rest and gives them time to tidy the mucus of the gut lining, helping to better regulate our health and metabolism, according to Tim Spector, the King’s College London professor who runs the ZOE nutrition app.
Giving your body, gut lining and gut bacteria more time to rest, recharge and repair itself, which can’t be done so effectively when a person is eating and digesting food, he has said.
A King’s College London study, run in conjunction with ZOE, reported in November that eating all your food for the day in a 10-hour window can significantly improve your mood, boost energy levels and reduce hunger.
This, the first real-world study into intermittent fasting (IF), found that nearly three-quarters of participants reported improvements in energy, while 57 per cent saw their mood improve and 47 per cent felt less hungry, according to a study of 37,535 intermittent fasters by King’s College London.
A 10-hour window means limiting your daily eating schedule to 10 hours and fasting for the remaining 14 hours. For example, if you eat your first bite at 9am, you must swallow your last mouthful by 7pm.
