It’s been a tough month since the shocking news of Dr. Michael Mosley’s passing. For his colleagues and friends at The Fast 800, the past weeks have been a whirlwind of emotions, both personally and professionally.
Michael was more than just a co-worker; he was a fountain of knowledge and a beacon of positivity. His warmth, humour, and unending drive for better health for all has left a void that’s hard to fill.
Michael’s groundbreaking work, especially through The Fast 800, has forever changed how we think about health and diet.
His insights and beliefs are deeply embedded in the program, ensuring that his legacy continues to inspire and guide us.
Hearing how Michael positively impacted so many lives has been truly heartening. His ethos will remain central to everything we do.
Read on to explore some of Dr. Michael Mosley’s enlightening insights and quotes on the topic of intermittent fasting:
What is intermittent fasting? Are there different types of intermittent fasting?
Intermittent fasting is popular in the health and wellness world, and for good reason. Ever since I wrote The Fast Diet in 2012 (an international best-seller which introduced the world to the 5:2™ diet as well as Time Restricted Eating), there has been growing scientific evidence of a multitude of health benefits that come from practising some form of intermittent calorie restriction.”
There are different types of intermittent fasting that offer varied health benefits. As well as the 5:2™ diet (where you cut your calories two days a week) there is Time Restricted Eating where you cut the hours within which you eat.
If you stop eating at 8 pm and don’t eat again till 8am the next morning, that is a 12 hour overnight fast, also known as 12:12.
If you stop eating 3 hours before bedtime that will also improve your sleep! A popular variant of this is 14:10, where you extend your overnight fast to 14 hours.
5:2 fasting: The 5:2 method of intermittent fasting is when you reduce calories on two days of the week.
While it’s evolved over the years, The New 5:2 involves two “fasting” days per week, where you consume about 800 calories of healthy and nutritious Mediterranean-style food and eat sensible portions of similar food with no caloric restriction for the remaining five days.
Alt: The 5:2™ diet involves two “fasting” days per week, where you consume about 800 calories of Mediterranean-style food and eat sensible portions of similar food with no caloric restriction for the remaining five days.
Alternate day fasting: This involves switching between eating with no calorie restriction on one day, to consuming zero calories the next.
On The Fast 800, we do not encourage this method for two reasons: there’s no significant benefit to fasting for longer than 16 hours, and consuming no calories at all for up to or beyond 36 hours is incredibly challenging for most people.
Time Restricted Eating (TRE): A popular form of fasting which is considered easy to follow and is encouraged while following any of the approaches on The Fast 800.
This method involves reducing the hours in which you consume calories (your eating window) and not consuming calories in any form outside of that (your fasting window).
Many people choose to take their fasting window overnight while they sleep and break their fast later in the morning, or finish their evening meal earlier. Often you’ll see TRE expressed as “fasting window: eating window”.
For example, 12:12 may mean you consume calories anywhere within a window of 12 hours, like 8am-8pm, and fast for 12 hours between 8pm-8am. Some people may choose to extend their fasting window even further, however, we recommend fasting a maximum of 16 hours to be sustainable long-term (expressed as 16:8, which, for example, could be eating between 12-8pm).
Alt: Time Restricted Eating (a form of intermittent fasting) involves reducing the hours in which you consume calories (your eating window) and not consuming calories in any form outside of that (your fasting window).
This can help regulate your appetite and prevent overeating, without necessarily reducing your portion sizes.
Alt: Time-restricted eating means you restrict the hours within which you eat. For example, if you do something like 14:10 that means you fast for 14 hours overnight, and then you eat again, but only within a 10 hour time window.
For example, you might stop eating at eight o’clock at night, and then not eat again until 10 o’clock next morning. That would be a 14 hour overnight fast.
There are other variants called 16:8 and 12:12, which is self-explanatory, but most of the science is now focused on what I would call 14:10. (That’s where almost all the research is being done.)
Professor Satchin Panda, is the chap who kick-started the important research surrounding the 14:10 model, and he is based at the Salk Institute in California.
What is the best length of TRE?
Popular forms of TRE are 12:12 (eat for 12 hours, fast for 12) or 14:10 (eat for 10 hours, fast for 14). While some people choose to practise 16:8 TRE, it is often unsustainable long-term and in order to suit your lifestyle. 12:12, where you might stop eating by 8pm and not eat again until 8am, provides a good balance between maintainability and health benefits. That said, much of the current research focuses on 14:10.
What are the benefits of intermittent fasting?
Intermittent fasting has the potential to improve brain function, prevent or reverse prediabetes and put type 2 diabetes into remission, as well as improve stress resilience and reduce inflammation.
Alt: Research has shown that intermittent fasting confers health benefits which extend beyond weight loss to include better sleep, reduced inflammation and improved mental health.
Alt: There is a lot of evidence for the benefits of intermittent fasting, if it is done properly. As well as helping with weight loss, studies have shown that it can improve sleep, blood sugar levels, blood pressure and mental health.
Burns fat: We all use two different types of fuel to function: glucose and fat. If you eat continually throughout the day, your body gets a continual source of glucose from food for fuel.
Any excess is then stored as fat. However, when you spend some time fasting, the glucose supply temporarily runs out, and your body has to switch to taking fat from your fat stores, which helps us lose the ‘visceral fat’ (fat associated with high cholesterol and high blood sugar levels), which lurks in and around the abdomen.
Helps you live longer: Short-term fasting activates a process within the body called ‘autophagy’ whereby dead, diseased or worn-out cells are broken down and gobbled up to make way for the shiny new cells that keep us young.
It also appears to reduce the rate at which your body produces a chemical called ‘insulin-like growth factor’, which appears to accelerate ageing and cancer in later life.
Boosts your energy levels: You might expect to feel tired and lethargic if you haven’t eaten for 12 hours, or you only ate 800 calories the day before, but intermittent fasting trips your body over into fat-burning mode and fat is a highly efficient fuel for your body and brain. This flip makes your metabolism work more efficiently, keeping energy levels stable.
Aids better sleep: Healthy sleep can also be compromised by overeating during the day and into the evening, but going to bed with a relatively empty stomach enables internal clocks in your digestive system to align with the clock in your brain so all your systems agree to go offline for sleep. It also causes levels of the sleep-promoting hormone, melatonin, to rise, which can help you fall asleep faster and stay asleep longer – and promotes the release of human growth hormone, one of your body’s vital resources for repairs while you’re asleep.
Reduction in inflammatory arthritis:
Researchers say intermittent fasting can reduce inflammation in the body, which helps reduce the risk of many different diseases, including arthritis. The reduction is due to a reduction in ‘monocyte’ cells during fasting, which is the cause of inflammation.
There are also additional benefits including reducing your diabetes risk, boosting brain power and mood, improving heart health and bolstering your immune system.
How does it aid weight loss?
Down the years there has been lots of research into the benefits of intermittent fasting, which include weight loss, improvements in blood sugars, cholesterol and blood pressure. As well as eating less calories, studies show that when you start doing intermittent fasting your body switches from using sugar to using fat as its main fuel source. It’s called “flipping the metabolic switch” and helps suppress appetite.
Can fasting improve my sleep?
Your body has a natural temperature drop before bedtime that signals it to prepare for sleep. Eating too close to bedtime raises your body temperature, delaying sleepiness. Try to finish your evening meal at least 3 hours before bed and consider fasting until the next morning to support circadian rhythm for better sleep. Good sleep equals improved weight management and overall health!
What to expect as we fast?
“By grazing all day or only briefly while we sleep, our bodies are forced continually to process the nutrients and toxins in our food, with little break. However, when we fast, our bodies get a chance to rest and repair.
Yes, you may feel a bit hungry as your body adjusts to fasting, but you will find that it keeps your energy levels steady, increases your concentration levels and aids better sleep.”
How often should we do it?
You can do the 5:2 and TRE as a way of life. The Fast 800 also has The Very Fast 800 approach (available in Keto too), where you cut your calories all week whilst eating a moderately low carb Mediterranean-style diet.
For this approach, I would recommend no more than 12 weeks or until you’ve reached your goal weight, whatever comes first.
Should you change up your fasting window or stick to the same routine?
This is really up to you. The most effective outcomes will come from a routine that suits your schedule and is one that you can stick to.
When should I eat on fasting days?
It’s crucial to pay attention to the timing of your meals. When you eat can be just as important as what you eat. Instead of constantly snacking throughout the day, try to stick to a structured meal schedule with regular intervals.
Should we still exercise?
There is some evidence that working out in a fasted state may be more effective in using fat as an energy source, however the differences are marginal.
Working out fasted vs. non-fasted is completely up to you and how you feel, some people love it but some people find it really tough. The most important thing is doing the workout, regardless of time in the day.
Can we still work and be productive?
Absolutely. Fasting is also beneficial for your brain health so once your body is used to it, you may find that you are even more productive.
How should we break our fast?
Your first meal after fasting should be something well-balanced that will fuel you well and provide sustained energy.
Protein is a must, ideally 20g or more, and higher fibre is also a good idea. Including healthy fats in your first meal will help to prolong the energy release as well. An omelette is one of my go-to breakfasts as it’s quick and easy to make, plus I add leftover roasted veg.
Does a coffee with milk (milk alternative) count as fasting or will it break your fast?
Adding milk to your tea will technically break your fast. However, we have found that a splash (less than 30ml) is usually okay and won’t affect blood sugar levels.
Why is fasting so popular when we’ve always been told that breakfast is the most important meal of the day?
A widespread misconception that originated as a marketing ploy from cereal brands is that breakfast is the most important meal of the day. Eating breakfast should depend on your schedule and preference: if you’re hungry, then eating a healthy, Mediterranean-style breakfast can be beneficial, and will help you keep your blood sugars steady.”
On the other hand, skipping breakfast if you’re not hungry isn’t harmful and won’t necessarily result in weight gain or an increased appetite later in the day time.
Furthermore, there is plenty of research that suggests that extending your fasting window (breaking your fast later in the day) has plenty of health benefits including improving metabolic health and increased weight loss.
Advice to a newbie starting their experience with intermittent fasting?
I strongly recommend that you begin by going to The Fast 800 website, not least because you need to know, before you start, whether it is right for you.
Broadly speaking, the programme isn’t suitable for people who have a history of eating disorders, people who are currently on certain medications or who have recently had surgery, or perhaps who are planning on getting pregnant etc (all of the fairly obvious categories).
The other thing, of course, is when you’re restricting your calories you must ensure the calories you’re eating are healthy ones.
You want them to be packed full of protein and other nutrients, so you need to make sure you’re following healthy recipes that meet your nutritional needs. The website takes the stress out of calorie counting by providing a range of tasty, easy-to-prepare healthy recipes.
Beyond that, you need to kind of tell your friends and family of your intentions to ensure you’re getting proper support, because certainly in the early days, it can be quite tough.
The good news is that people say that they are surprised how quickly they get into the pattern and they very quickly stop feeling hungry. I think it is also important to clear out your cupboards and get rid of the junk food because unfortunately, if your cupboards are still full of junk food, it’s very tempting when you’re feeling a little bit peckish in the middle of the night! I know that if I have chocolate and biscuits in the house, I will eat them, despite everything that I know, so my advice is to remove temptation. There’s a fair amount of pre-planning that needs to go into it if you’re going to be successful. Rather just jump into it, do read about it first. Have a plan, work out what you’re going to do, inform your friends and family and then get going.
How many low-calorie non-starchy carbs can I eat on fasting day?
There’s no need to count the extra calories (even on fasting days.) Fill your plate with colourful, low calorie non-starchy vegetables like broccoli, spinach, cauliflower, mushrooms and dark leafy greens. These are rich in vitamins, minerals, fibre, and antioxidants.
How much protein should I eat on a fasting day?
Allocate at least 60g of high quality protein on fasting days (and a little more on non-fasting days).
This can include options like meat (chicken, beef, lamp, turkey and more), eggs, fish and seafood, beans and legumes and wholegrains, tofu or tempeh.
How do individuals manage hunger and cravings while following an intermittent fasting regimen?
The main thing is to eat healthy foods that are satiating. That means lean protein (fish, chicken, eggs, tofu), olive oil, nuts, and full-fat yoghurt. You also need fibre, which means veg, whole grains and legumes.
Also, try to make sure you are drinking a large glass of water with every meal as you will lose a lot of water when you are losing weight. If you are dehydrated then this can lead to headaches and constipation.
You also need to be aware that it can take you a week, maybe a bit more, to adjust to a new way of eating.
Once your body is used to it, you will likely feel mentally sharp and physically energised, you might sleep better too.
What are some of the most common mistakes you see women/people in general making with fasting?
Overeating on non-fasting days or eating the wrong foods: Yes, non-fasting days technically have no restrictions, however, this shouldn’t be taken quite so literally.
We recommend eating a Mediterranean-style diet and following a meal plan, like The Fast 800 programme, to ensure you’re getting the right nutrients and don’t overeat on non-fasting days.
Scheduling fasting days when you’re having a quiet day: Instead, try to schedule them when you’re going to be kept busy. In saying that, avoid scheduling them when you have a social event to attend. Fasting days are flexible and they should work around your schedule.
Is there anyone who shouldn’t do it – e.g. girls when menstruating?
Intermittent fasting is a safe and effective approach for most people. However, If you are on medication, are pregnant, breastfeeding, underweight or have a history with eating disorders, you should speak with your GP for support and guidance first. You can find out more by visiting The Fast 800 website.
Your menstrual cycle can be affected by fasting, so it is important to pay close attention to your cycle as you make any dietary changes.
TRE is usually well tolerated and unlikely to affect hormones through the majority of your cycle; but in the week leading up to menstruation, when progesterone is higher, fasting can disrupt hormones.
Are there any new studies in the pipeline or research that’s coming?
Yes. There are always interesting new studies being carried out. There is still a lot of interest particularly in The Fast 800 approach, and there have been a number of big trials recently in the UK and Australia, looking at the benefits of this approach for things like type 2 diabetes, but they’re also looking at it for other conditions now like fatty liver disease, dementia as well as brain diseases. There is a huge interest in areas like dementia and cognitive decline, because they’re massively on the rise, so it’s not just about weight.
Dr. Mosley’s Enduring Influence
Dr. Michael Mosley’s legacy in health and diet is monumental. His work on intermittent fasting, particularly through The Fast 800, continues to inspire and benefit countless people. The principles he established are at the core of The Fast 800 program, ensuring his vision lives on.
In honouring his memory, the Fast 800 team remains dedicated to providing accurate information on intermittent fasting, supported by clinical studies and delicious, healthy recipes.
Dr. Mosley’s teachings and insights will continue to guide us towards better health and well-being.