Can Intermittent Fasting Really Boost Fat Loss?
Breakfast is considered by many to be the most important meal of the day.
Even if you're not hungry or hate eating early, you dutifully follow this received wisdom orders and stuff food down your neck as you start the day.
But what if we told you that eating regularly from the moment you wake up isn't critical for health and a well-functioning metabolism?
What if we told you breakfast might not be 'the most important meal of the day?'
This is the belief of a growing number of people following an intermittent fasting protocol who think that skipping breakfast all together and fasting throughout the morning is the key to better health and body composition.
Intermittent fasting (IF) is a concept that is taking the fitness and nutrition world by a storm at the moment.
While humans have been fasting for centuries due to food scarcity, we’re now doing it by choice.
Fitness junkies everywhere (including myself) are trading in their bulletproof coffee along with their meat and nut breakfasts.
So can changing when you eat rather than what you eat really help you lose fat and build a better physique?
What is IF?
IF isn’t a diet, but rather a pattern of eating. It involves alternating between periods of fasting and eating. The main goal of IF is to force your body past the absorptive state into a prolonged fasted state, so it uses stored fat as energy.
Fed vs Fasted
Absorptive State (the fed state):
You enter this state pretty much the moment you start eating, and it generally lasts for approximately 3-5 hours after you finish.
Your body is in the absorptive state when it is actively digesting and absorbing food.
Your body is using absorbed nutrients to meet immediate energy needs, and converting any excess calories into stored energy. Insulin regulates the absorptive state.
After your body has completely finished digesting and absorbing your last meal, you enter the post-absorptive state (around 8-12 hours after your last meal). During this state, fatty acid oxidation contributes a significant amount more to energy expenditure than carb oxidation. Essentially, your small intestine and stomach are both empty, and your body has to use energy that has been stored previously to function. Insulin is generally low during the post-absorptive state.
In a truly fasted state, insulin levels are very low and your body has to burn fat for fuel, which is the main reason people try IF.
Fatty acids enter the bloodstream and are converted to ketones, which are used for energy.
But it takes 12 hours after your last meal to enter a fasted state, meaning most of us are rarely in one.
With IF you force your body to regularly enter a fasted state.
According to some researchers, this may come with body composition benefits.
Initially, when starting an intermittent fast, it's even suggested to keep calories the same. The introduction of the fast alone may be enough to induce fat loss whilst keeping calories constant.
Some believe IF will help you lose fat whilst preserving muscle mass. Additionally, IF makes it more difficult to overeat throughout the day as your eating window is smaller. This makes it easier to maintain a lower body fat percentage once you achieve it.
But IF may have benefits that go beyond aesthetics. Dominic D’Agostino, professor and senior research scientist at the Institute for Human and Machine Cognition (IHMC), suggests that IF may play a part in postponing or even preventing neurodegenerative disorders like Alzheimer’s and Parkinson’s disease.
Studies dating back to 1945 proved that IF extended the life of mice. More recent studies on humans show that alternate day fasting increases SIRT3 proteins, which scientists believe are responsible for longer lifespans.
IF has been shown to increase insulin sensitivity, therefore reducing the risk of type 2 diabetes. It’s also been shown to reduce inflammation, blood pressure, and “bad” cholesterol.
Due to its rapid rise in popularity, there are already multiple IF methods to choose from:
1. Leangains Method
The Leangains method is the most popular IF method. With Leangains you alternate between 16-hour fasted periods and 8-hour feeding periods. You can schedule the meals whichever way works best for you. If you're not a morning person and you have to force down your breakfast, start eating at 12 noon and finish at 8pm. If you NEED breakfast every day, adjust accordingly. There are a few more rules that come along with the Leangains method.
Your diet should be high in protein, and you should follow the basic principles of nutrient timing (eating the majority of your carbs post-workout, etc.). You should also include fasted training.
2. Alternate Day Fasting
Alternate Day Fasting is pretty simple; on this plan you eat every other day.
On “eating” days, you eat within a 12-hour window. For example, you could eat from 7 am to 7 pm on Monday.
You would then fast until 7 am on Wednesday. Some people follow a modified approach where they interpret fasted days as restricted days.
On the “restricted” days they consume fewer than 600 calories, but don’t actually fast. During feeding days, you can essentially eat what you want without limit.
3. Meal Skipping
Meal skipping is the free form, hippie version of IF. Proponents of this method try to mimic the eating patterns of our evolutionary ancestors. In the hunting and gathering days, people didn’t have constant access to food.
With this method, you’re encouraged to randomly skip meals a few times a week. Food choices should also be close to what our ancestors ate. Essentially meal-skipping is a Paleo diet whereby you randomly skip meals here and there.
Eat Stop Eat is an IF plan developed by Brad Pilon in which you fast for 24-hour periods up to two times per week (never on consecutive days). Food choices aren’t restricted on eating days as he theorises that fasting even once per week will put you on a weekly 10% caloric deficit. However, you are urged to eat a normal-sized meal when coming off a fast (so don’t shovel food into your mouth until you feel like you need to chunder), and to generally eat within reason.
5. Warrior Diet
The warrior diet involves 20-hour underfeeding periods, making it suitable only for the hardcore intermittent fasters.
With the Warrior Diet, you alternate between 20-hour periods of underfeeding while sleeping and during the day, followed by four-hour periods of overfeeding (a binge eater’s dream).
During the underfeeding periods, you can still consume fruits, vegetables, and small amounts of protein.
Anything substantial must be reserved for your overfeeding period. You also complete your workouts throughout the day.
My Experience with IF
When I delved into IF, I decided to go for the Leangains method, because it’s the most sustainable for my lifestyle and mindset.
Truth be told, I love to eat. So the thought of voluntarily fasting seems sadistic and unnatural to me.
The word “fast” alone makes my skin crawl. However, given the proposed benefits of IF, I was willing to sacrifice some eating for the greater good. Periods of 16-hour fasts seemed much more realistic than full days of going without eating.
The night before the fast I ate my dinner slowly, enjoying every last bite knowing that I would have to say goodbye to my beloved food for longer than usual. I woke up the next morning excited, and eagerly completed my fasted cardio at the gym bright and early. Since I started my fast at 8 pm I only had to fast until noon, which seemed somewhat reasonable to me.
By 9 am, I had already been up for three hours, and I was feeling it. Admittedly it was more mental than anything. Lots of people regularly skip breakfast without a flinch.
But being forced out of my habit was somewhat painful and I was missing food already. The morning crawled by and my eyes were glued to the clock waiting for the moment I would be able to eat again. Thinking of my turkey patty and roasted cauliflower, which usually seemed mundane, was causing me to salivate. The thought of cutting the fast short by half an hour crossed my mind, but I held out.
The first day was the hardest. Getting through the week wasn’t too difficult because the routine of work was distracting and the mornings started to go by quicker.
The weekends were more challenging because no work means more time to think about when you’ll be able to eat next. Admittedly I’m also an intolerable b**ch in the morning until I’ve eaten, so IF was fairly taxing on my significant other. But we both persevered.
After two weeks I no longer felt too hungry in the mornings, and no longer anxiously awaited the second that I could eat again like a drug addict waiting for their next fix. I was actually starting to feel quite energised.
The headaches that I experienced throughout the first few weeks were gone. I had also grown accustomed to drinking more water, as I would guzzle it when I felt hunger pangs throughout the morning.
Intermittent fasting was actually a small behavioural change that made it easier for me to incorporate other healthy habits that I had always put on the back burner. I was getting in at least 2-3 litres of water per day, I never missed taking a supplement, and my morning cardio became habitual.
If you can’t eat in the morning, what else do you have to do? Also, when you’re sacrificing and suffering for your body composition, you’re motivated to do all the small and easy things as well.
Is it For You?
It's all about context for clients we work with at Ultimate Performance. It may be useful for a minority of clients but it always depends on the individual and their goals.
One thing we would advise is certainly trying to shift clients from moving from just grazing around the clock to using a 12- or even 10-hour eating window which can be beneficial while keeping appetite in check.
Disclaimer: If you’re a habitual binger, IF isn’t for you. The cycling between periods of eating and fasting can hit too close to home for yo-yo dieters who for years have cycled between periods of serious deprivation and over-eating. You’re better off sticking to regular eating patterns and intervals.
IF is ideal for people who struggle with the small portions that often accompany a diet. Often when dieting, meals are whittled down to sorry displays of a few strips of meat alongside some vegetables, leaving much to be desired. If you’re fitting the same number of calories into a smaller timeframe, you can enjoy bigger, more satisfying meals.
IF is also an excellent way to learn how to manage hunger. The bottom line is if you want to achieve a low body fat percentage, you’re going to have to reduce your calories down and suffer a little (sometimes a lot).
Following a controlled fasting protocol with IF forces you to push through your hunger. This experience can make controlling hunger easier when you’re no longer intermittent fasting.
Find Out For Yourself
So will IF help you lose body fat? The current research on IF is not completely conclusive. The best way to find out is to give it a go.
Because the mental component of dieting is so instrumental to fat loss success, your mindset and behavioural patterns will play a huge part in which IF method works for you, or whether IF works for you at all.
If you want help achieving your health and fitness goals with a bespoke training and nutrition plan to get optimal results, simply enquire below...