Intermittent Fasting: Top 10 FAQs Answered
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Because the science on this latest diet fad is so flimsy, and because the fitness media has whipped IF up into such a frenzy, it is important for us to start you off with some common FAQs.
Is there any specific 8 hour window that works best for 16/8 IF?
Not really. Remember that at its core, IF is just a tool to help you restrict calorie intake. So you could, theoretically, eat from 8pm to 4am if you so wished. But practically speaking, for most people, 16/8 IF will boil down to 2 options: Skip Breakfast or Skip Dinner. Now between these two, I suggest you chose basis just 3 parameters:
1. When do you workout?
2. What do you find easier — staying hungry in the morning or sleeping on an empty stomach?
3. Do you have many evening social obligations?(a.k.a do you go out a lot)
I’ll explain parameter one in a subsequent question. Parameter 2 is self explanatory. And 3 is a lifestyle choice. I don’t go out much and I don’t mind saying no to food even if I’m out with friends. But if you do, then from an adherence point of view, you’d be better off skipping breakfast. I chose a feasting window of 2pm — 10pm because I workout at around 8pm and I can not sleep on an empty stomach. Simple. No other consideration. Some studies do suggest that skipping dinner helps you burn slightly more calories during the day compared to skipping breakfast (we’ll talk more about this soon). So it might have a slight edge.
What is important though, is that you stick to whichever schedule you pick. Setting up the routine will not only help you adjust, it’ll help your body predict and understand the pattern and optimise for it. So above all, do what you can keep doing.
What! How can you Skip Breakfast?
Isn’t it the most important meal of the day? This is a tough one. Tough, because I’m guilty of having fallen for the same truism for years. Somehow, somewhere, we all started believing this to be true. None of us, including me, ever stopped to ask — Why? And why would we bother! Many of us (again me) love breakfast! Who doesn’t want to eat a croissant and a cheese omelette and some juice and some Chocos right after they get up! You’re famished and it’s socially approved to hog! No other meal hits that sweet spot.
So I went back and researched where this ‘breakfast thing’ started. As it turns out, it was good advice, but for a specific purpose. And then the marketeers came and advertised it into gospel truth. Let me explain.
As I’ve said many times before, calorie restriction is the basic truth of weight loss. Keto, IF, Paleo etc. can all fasten it and make it more fat-efficient, but no one lost weight eating 4000 calories a day.
Now before IF came into the picture, the only way to restrict calories was to restrict them throughout the day. So you reduce, say 20% calories, from each meal. But that, researchers found, wasn’t the most optimal way.
When you get up, your metabolism, which is severely impeded while sleeping, fires up again.
So they concluded that if you consume most of your calories in the first half of the day, when you’re most active, and keep reducing intake as you near sleep time, your weight-loss results will be better. Which is absolutely true! But that’s where the US fitness-marketing machinery came in. And just like everything they touch, converted this scientific insight into fecal matter. Their insight, you see, was that no one skips dinner because they’re too busy. But people do skip breakfast. So if you could persuade them to never skip breakfast — you could earn a lot of money selling them…breakfast! Oh and like I explained in this article about sugar, post the great depression, the US had a lot of corn and didn’t know what to do with it.
Lo and behold… The Breakfast Cereal!
Two birds with one, sugary stone! And the birth of the ’Never skip breakfast’ marketing campaign.
In a hurry? Don’t worry! Have Cornflakes dipped in High Fructose Corn Syrup -every morning.
Can it get more corny!
So is it good to skip breakfast?
Let me re-iterate. Breakfast isn’t bad. It’s great. Have it if you must (and can still keep under your calorie quota).
Infact, there are studies that establish that a ‘good’ breakfast can help fire up your metabolism and keep you more active through the day.
There are also studies (not enough though) that show that people who skipped dinner on IF lost more weight that breakfast skippers. Which again makes sense given the metabolism point earlier.
The problem hence, isn’t breakfast. It’s what you eat for breakfast. If the answer is Cornflakes and Chocos and Fruit-Loops. Or croissants and muffins and doughnuts (notice how all of this, ALL of this, is from the USA?) — then it is BAD.
Most cultures across the world eat largely protein (egg, sausages, cold-cuts) for breakfast. Even the carbohydrates they consume (potatoes or veggies in India, whole grain breads in Europe) are all complex, low-gi carbs that don’t spike your insulin levels as soon as you wake up! And also fill you up with nutrients.
It was the US’s breakfast marketing monster that put sugar dipped cereal into our system first thing in the morning. And the resulting, massive insulin spike right after you wake up, is the worst thing you can do to your system.
Because once spiked, your insulin senstitivity decreases for the rest of the day. Which not only makes you lethargic (ever felt like hitting the bed after a big fat brunch?), it also makes your body prone to storing more of it as fat.
Simply put. Eat simple-sugary-carbs in the morning, and you’re more likely to eat a lot more during the day, feel lazy, and get fat. If this is your breakfast, much better you skip it. If you’re having a veggie+protein heavy breakfast — there is no harm. Have a big one. Just manage your overall calories and you’ll be good. Alternatively, there is nothing wrong with skipping breakfast either. Remember that ‘breakfast’ is whenever you break your fast. It can be at 2pm also. Just make sure that whenever you do, you’re consuming proteins and complex carbs and nutrients. Not sugar.
When should I workout while on IF?
I’m personally of the opinion that you should make IF fit your workout routine and not the other way around. If you already have a set routine, don’t disturb it. Because then you’ll be trying to sustain two new habits and that’s exponentially tougher than one. What’s important is the post-workout meal. So your IF timing should be such that you eat your biggest meal of the day (~ 50% calories) right after you work out. This is the time when your muscles need the nutrients to repair the damage you did in the gym. So you definitely don’t want to deprive your body at this time.
Is it OK to workout on an empty stomach?
This is another tough one, with a different answer basis goals.
If you haven’t eaten for a while, your energy stores (glycogen) will be depleted. And your ketosis mechanism for burning fat as fuel would’ve barely begun. So chances are, you wont have the energy needed to put in a good workout (high intensity).
If you’re trying to maintain muscle mass during IF, then this isn’t ideal. We spoke about it here — you need to keep lifting heavy to even maintain muscle mass. If you find you’re too weak to do so — I wouldn’t recommend empty stomach strength training.
But equally, if your aim is fat loss, doing medium intensity cardio in a fasted state might yield better results. It might help kick start your ketosis mechanism, which is great for fat-loss.
So the answer depends on your fitness goals. And on personal experience. Ideally, time your IF so that your workout falls somewhere in the middle. That’s best according to me.