Does intermittent fasting keep popping up on your instagram feed, have you seen it mentioned on social media or does you favourite celebrity practice it?
Here is a beginners guide on what it is and how to get started. If you want to know more of the scientific basis please read my take on the insulin theory.
THIS IS NOT A DIET NOR IS THIS A FORM OF STARVATION! I think it is important to make this clear from the outset, Intermittent fasting (IF) should be thought of as eating a healthy balanced diet during a specified period of time; some people even prefer the term time restricted eating.
Human beings are not designed to constantly eat food, at all times of the day, and extensive research has shown the body has an internal clock which controls genes, making them more or less active at certain points in the day.
IF uses this knowledge to maximise the body’s own signalling pathways and works to ensure that these signals are released at a time when they are most likely to be efficient. Having periods when the body is in a ‘rest’ state is also equally important, as it gives the body ample opportunity to carry out essential repairs, which is important for overall health and wellbeing. It also been shown to aide weight loss.
How does it work?
It’s very simple and no special diets, drinks, shakes or food are required. There are variations in how the fasting is carried out, but one of the most popular, is the 16:8 method. This refers to eating in an 8-hour window and omitting food for 16 hours. There are many variations and generally this relates to the amount of time you fast but it generally accepted the minimum amount should be at least 12 hours although some people have one meal a day and can fast up to 22 hours. The important thing to remember is it’s not the window during which you eat, it’s the period of time where you DON’T eat that’s key, as it’s at this point you start burning fat.
If you are overweight, your body is used to having high levels of circulating glucose and insulin. It takes some time for your body to learn how to access its fat stores and become ‘fat adapted’. It’s not uncommon for people to say they feel dizzy or lightheaded when they miss breakfast or a meal, this is because the body gets used to eating food at a certain time and wants to access energy with the least amount of effort possible. More often than not it will use up your easy access glycogen stores first, when these run out, you get the signals to your brain telling you that you are hungry. It may take a few days/weeks to overcome this feeling. When the body is fat adapted, it efficiently uses up the glycogen stores and starts burning fat when you do not eat in a seamless way, so you don’t not notice that hunger.
Therefore, my advice to anyone starting IF is to approach this in a stepwise manner. Start by fasting for maybe 12-14 hours, and for most people, this means not eating anything after their evening meal until breakfast/midmorning the next day. Drink plenty of fluids during this time so you are not dehydrated. If you feel fine, increase the periods of fasting slowly. Remember IF should be thought of as a way of life, rather than a quick fix solution, so take the time to invest slowly into it.
When should I eat?
This is entirely up to you. Think about what works best for you and your working day. Sometimes people find that being busy at work distracts them from their hunger and so can open later in the day. So they open their window at 12 and then close by 8pm in the evening. Others have breakfast and big lunch and then don’t need a large dinner, so open at 7am and then close by 3pm. Consistency is important and, where possible, fast daily and try to stick to similar windows. When you are inconsistent the body gets confused and makes it think it may be in starvation mode, making it harder to lose weight.
But as already mentioned, IF is a way of life and life needs to be flexible, so if you have a social engagement during a time you would normally fast, you can alter your window and make it longer or shorter.
What can you consume when you are fasting?
During your fast you are not allowed to eat ANY food, or anything that might cause an insulin spike; this includes milk. However black or green unflavoured tea, coffee, water, sparkling water are all ok, as they don’t contain anything to spike your insulin. There is also some evidence that black tea inhibits gherlin, a hormone released by your body that stimulates hunger. Wedges of lemon, flavoured water, herbal teas, even earl grey are a bit of a grey area – they contain components that may trick your body in thinking you are eating food and so raise your insulin level, which then triggers feeling of hunger.
It’s also a good idea to drink plenty of water (still or sparkling) to keep yourself hydrated.
What do you eat in your window?
Anything you want! Gin Stephen’s uses the great phrase “delay don’t deny”! This is one of the amazing benefits of IF: it’s not restrictive in any way, as your body learns to process energy from the food it consumes in the efficient way it is designed to.
Usually when people start IF they feel the need to gorge on everything and anything. This is fine to begin with, but doing IF daily and consistently you will find that your appetite starts correcting itself. When insulin is raised for long periods it suppresses your satiety hormones, so you eat beyond the point of hunger. With time, IF reverses this and you start becoming aware that your body is full and encourages you to stop. Also, as you are not ‘denied’ anything you don’t get the same bingeing phenomenon. But the key thing is that you stick to eating only in your windows.
I said at the beginning that IF is not a diet, it’s a way of eating. This makes it a great opportunity to reassess the relationship you have with food. If you are only eating in a smaller window think about fuelling your body with healthy nutritious food, rather than indulging in too many treats. For most people, an 8 hour eating window usually means that people eat two meals, without the need to snack in between.
In theory you can eat whatever you want – low carb, high carb, keto, paleo, vegan, vegetarian, etc. Remember though, during this period you need to consume all the things that need to keep your body nice and healthy, so approaching it sensibly will keep you healthy and ensure that it is sustainable for you.
Eating meals that are high in good fats and different proteins will keep you feeling fuller for longer. So try and include plenty of nuts, seeds, cheese, avocados, eggs, proteins, and healthy oils like olive oil. They also stop the sugar high and lows that you can get with have a carbohydrate heavy meal, reducing the need for you to snack.
What about treats?
As already discussed you can have treats in your window, because your body will start learning to process excess calories and sugar more efficiently. It is important to add though that treats such as cakes, donuts, pastries etc, are high in sugar, trans fats and usually highly processed. Having high quantities of these in your diet is harmful to the body and lead to long term damage and consequences.
In practice people find that their desire for unhealthy treats changes with time, they become more in tuned to what their body needs, and end up eating less. As there is no denying, there is no need to ‘binge’, no food is off limits and no food is considered cheat food, it’s all just food. Thinking of it in this way stops the ‘diet’ mentality and helps readdress the relationship we have with food.
How quickly will I notice a difference?
Remember, this isn’t a diet. It can take a few weeks for your body to realise that something new is happening. A great tip is to take measurements of your chest, waist, arms, and thighs alongside your weight. There will be times when the scales don’t change, but there are often changes in body re-composition, and you may notice that your trousers are looser. The other thing I also suggest is taking some photos when you start the process as this will allow you to really see the changes, and hopefully motivate you to continue the process, even if the scales don’t move.
Other than weight loss what are the other benefits of IF?
Studies have also shown intermittent fasting to promote longevity, speed up the metabolism, strengthen the immune system and preserve lean muscle mass.
IF stimulates growth hormone production and this can make skin appear smoother and encourage muscle production, so often the body appears more toned.
When fat is broken down it releases ketones, and these are thought to make you more alert, improve brain function and can help you work better.
Sleep is often better, as the body does not need to waste energy managing excess sugar and making fat, when it should be doing essential repairs at night. This is particularly true of the gut, and often symptoms such as bloating and bowel discomfort are reduced.
Will I feel hungry?
It can be daunting! People really fear hunger, and that is understandable, food is essential for our survival! However if you are overweight your body has enough food reserves in its fat stores. I heard a great expression that hunger is a signal, not a command. Many times other signals related to thirst, tiredness, boredom and stress get mistaken as hunger. So if you do feel hungry go through this checklist of questions:
– Am I really hungry?
– When did I last have a drink?
– When did I last do something active?
– Do I need to have a few minutes break from what ever it is I’m doing?
– Am I feeling tired/stressed/bored rather than hungry
This should help you decide if you need to break your fast early.
Start gently, perhaps with a 12 hour window and then gradually build up with the aim to get to 16-18 hours. Your body does get used to it fairly quickly. What’s the worst that will happen if you don’t eat for a few hours?? However remember if your windows of eating are large (8-14hours), you need to be really careful about what you are eating during that period, and I would strongly encourage you not to snack.
Finally if you are fasting clean for long periods and you are still feeling hungry on a daily basis, focus on what you are eating in your window. Are you providing your body with enough fuel to give you the energy that you need, if you are not, think about meal planning and look to see where you can make changes.
What if I have medical health issues?
If you have an underlying medical health condition, please discuss it with your doctor before commencing intermittent fasting. It however can be helpful, in many conditions but does require expert medical input.
Can I take medication?
Of course, take your medication as prescribed. However, if you are diabetic I would strongly encourage you to discuss this with your doctor as your medication may need to be altered.
Can I exercise?
This is a common question that many people are concerned about and yes it is perfectly safe to fast whilst exercising. Exercising is essential to losing weight and staying healthy, and it is something i would strong encourage.
Fasting stimulates growth hormone, it also burns fat by preserving lean muscle mass. Many athletes, body builders and professionals incorporate intermittent fasting into their fitness regimes.
If you are new to fasting, I would suggest starting slowly, build up your fasting times and be confident that you feel well. It may be sensible to discuss it with your personal trainer or exercise coach. For some people who do intensive exercise or have specific exercise goals they may need to tweak when they eat to prevent injury and maximise the positive effects of exercise.
What can I do to support my fasting?
Try involving family members or colleagues, or join a Facebook group or online fasting forum, having others to support and encourage you, will make it more likely for you to succeed. It also give’s you the opportunity to share ideas and troubleshoot any problems.
Many people also use a fasting app like zero/vora to track the length of the fasts, and also happyscales to monitor weight loss.
Do I need any supplements?
If you are eating a balanced diet there is no need for additional vitamins. However sometimes people can experience muscle cramps and constipation, and there is some evidence that taking magnesium supplements in the form of Himalayan pink salt or magnesium citrate 10mg may provide some relief.
What if I eat by accident?
Don’t worry, this is a learning process. We all make mistakes and you are not in competition with your self, the key thing is we don’t beat ourselves up and we learn from it. Intermittent fasting goes hand in hand with the concept of extending loving-kindness to ones self and being mindful of everything around you. Some days maybe easier than others, and other days things happen to make it feel like a struggle, and that’s ok. Learn ways of managing your thoughts, feelings and emotions.
I hope this guide is enough to get you started, if you have questions, comments or you would like to share what has worked for you, please send me a message below.
Disclaimer: The information expressed in this article are my own personal views. This information does not constitute medical advice and it should not be relied upon as such. If you have any underlying health conditions or take regular medication I recommend that you consult your physician before commencing any intermittent fasting.