Intermittent fasting 101 – Everything You Need To Know About Intermittent Fasting In 2020

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You’ve done it. I’ve done it.

There’s been a day you were in such a hurry that breakfast was not even on your mind. Or you slept off early only to wake up the next day….. you’ve missed dinner.

It’s one of the trending topics in the health and nutrition community.

Losing weight is one of the primary reasons people do it.

It has also been shown to have other health benefits to the body.

This is an absolute beginner’s guide to intermittent fasting. So if you want to learn more, buckle up.

What is intermittent fasting?

As the name suggests it’s catching a break from eating.

It is not a dieting routine because it does not specify what to eat or not. It’s more of an eating pattern.

It basically divides your day or week into two portions. Periods where you can eat and periods where you fast.

Fasting is not really a new thing to us today. We’ve done it for several reasons.

One being religion. There are periods in a religion when it’s people are advised to keep a fast.

Since time immemorial, man has had to adapt to shortage of food sometimes,hence starve. The body has evolved to function both in fed and fast states.

What is fed and fast state?

When you’re done eating, you become satisfied and sort of lose appetite for more food. This is you body telling you it’s full.

During this time your body is absorbing the food. This results in increased levels of sugar(glucose) in the blood and increased levels of insulin as well.

So the body easily gets its energy from all the readily available glucose in the bloodstream. The excesses are stored as “glycogen” and fat. Though the fat is locked away and can not be touched.

This is called the Fed state.

Several hours after your last meal, you glucose and insulin levels are going down. The body needs to keep functioning.

But where would it get the energy from?

Now the stored energy for becomes available. First off, glycogen is degraded and used as an energy source but it too does not last forever.

Remember the locked away fat? Yeah….it becomes accessible now. So in the absence of enough glucose the body turns to fat as a source of energy.

This is called the fast state

fed state vs fasting state

How is it done?

As said before intermittent fasting is more of an eating pattern. So there a different methods by which this can be achieved. Some of them include;

  • Alternate day fasting: This involves switching from a 24 hour fast day where you eat nothing or about 25% of your normal calorie intake followed by a 24 hour non fast day where you eat normally. In essence,you fast one day you eat the next day.
  • Periodic fasting: Here you fast for periods longer than 24 hours. An example is the 5:2 diet. With that you have 5 non fast days and two fasting days. During the fasting days you can either eat nothing or just about 25% of your normal calorie intake
  • Time restricted feeding: It involves breaking up your day into fast and non-fast hours. A popular example is the 16:8 diet where you have 16 fast hours and 8 non fast hours. It usually involves skipping breakfast and restricting your eating period to 8 hours.

How does it affect your body?

By fasting you’re basically telling your body to dip into it’s reserve.

During your fast periods, the level of glucose and insulin in your blood drops. A few hours into fasting, your body makes use of a stored form of sugar called “glycogen”.

It is stored in the liver as a form of emergency backup when the body lacks glucose. It is then broken down to be used as an energy source for the functioning of your body.

It too will be exhausted after some time……so what now?

The body then bares it fangs at the fat storage.

Now, the body starts breaking down fat as an energy source. And it is quite a good one at that, as it gives off more energy per unit than glucose.

Intermittent fasting also increases growth hormone secretion and insulin sensitivity. With growth hormone being produced more, the body is primed for growth.

The million dollar question – how does it affect your weight?

It’s usually the reason why many people get into intermittent fasting. So how does it really affect your weight?

First, let’s talk about it’s impact on your calorie intake. I’m going to use the 16:8 method as an example.

Before you started intermittent fasting,you do have a three square meal each of about 1500 calories on the average. That’s a total of 4500 calories per day.

When you started intermittent fasting, you decided to cut off breakfast and do with just lunch and dinner.

Sure, your lunch and dinner might be bigger than it used to be. So let’s say about 1800 calories on an average for each. This brings the total to 3600 calories per day.

From this simple example you can see that intermittent fasting automatically reduces the amount of calories you take per day by 900 calories. And that is a very important step towards weight loss.

And of course for it to work, you don’t have to drastically change the amount you eat. In the example above, let’s say you went ahead to eat lunch and dinner each of about 2500 on average.

Then there is no point to your fasting as you’re defeating it’s purpose. So remember not to binge during your eating period as a revenge for cutting breakfast.

Additionally, intermittent fasting alters hormone levels to make fat loss easier.

It reduces insulin level while increasing it’s sensitivity. Increases growth hormone production and also a hormone called “norepinephrine”.

All these makes fat the preferred source of energy for the body. And also increases the basal metabolic rate.

So you get to add more muscle mass while you losing the much hated fats. Boo yeah!

There are studies that have shown that intermittent fasting can reduce your weight by 3-8% over a couple of weeks.

What will I gain from intermittent fasting?

Many studies have been done on intermittent fasting though some are still at early stages. There are several health benefits that comes with fasting.

Weight loss: The calorie reduction and hormonal changes makes it easy to lose weight. Just remember not to binge.

Cardiovascular health: Studies have shown that intermittent fasting helps reduce bad cholesterol in the body. This results in an overall good heart condition

Insulin resistance: This is one of the major causes of diabetes. Intermittent fasting increases insulin sensitivity thereby lowering blood sugar. It also decreases the overall insulin level. Therefore it is protective against diabetes.

Brain health: It leads to release of certain factors in the brain that helps nerve growth and repair. It also protects it against degenerative diseases like Alzheimer’s.

Cancer: Though the research is still preliminary, it suggests that intermittent fasting can prevent cancer. And reduce the chemotherapy side effects in those being treated.

Is it good for everybody?

Well, I’d say if you feel you don’t need to then don’t bother. It’s not something that is necessary for everyone to do. It’s just like a lifestyle. If you decide to join in then fine.

But certain people are advised not to even though they might want to. Like;

Underweight people: If you’re underweight there is no point engaging in intermittent fasting because it might worsen your case. You need to eat more.

If you have an eating disorder, embarking on an intermittent fast might be dangerous. Consult your doctor first.

Pregnant and breastfeeding women should not participate in intermittent fasting. It may prove harmful to their health and that of the baby.

It goes without saying but if you have a underlying medical condition, consult your doctor before doing the intermittent fast. Like diabetes, low blood pressure, etc

Side Effects

Even though you’re not taking a drug,there might be some side effects.

The major one is hunger. It’s easy to understand why. You don’t eat as much as you used to anymore.

Others include impaired focus, low energy and irritability.

The good thing is that they are temporary and will go away with time.

You just made a change to your eating pattern, so your body is still trying to adjust to it. Once it does, those side effects will go away.

Some Frequently asked questions

Isn’t missing breakfast harmful?

We’ve always been told that breakfast is the most important meal of the day….. that’s my mom’s mantra.

But is it really harmful? The answer is no.

Once you eat good food eventually during the day then you are fine. The thing is that most people who miss breakfast do not eat right for lunch or dinner, hence the saying.

Can I take liquid during the fast?

Sure. You can take tea,coffee and water. Or any other liquid that doesn’t contain calories. Don’t add sugar to the tea or coffee but you can add a bit of milk.

Can I workout while fasting?

Of course. In fact some people see this as a good way for high intensity workout for short duration. As it tends to enhance lipolysis therefore you build muscle while losing fat.

Should children do the intermittent fasting?

It’s not advisable for children. Their bodies are still developing and has a different requirements from adults.

Can I take additional weight loss supplement?

Yes, there’s no harm in doing that. A weight loss supplement will enhance the weight loss activity of the intermittent fast.

What do you think – should you try it?

As I’ve said before, it’s not for everyone. One you’re healthy enough and want to try it, then by all means go on.

Let’s leave the science for a bit.

What’s one of the best benefits of intermittent fasting?

It makes your life simpler. One less stress to put up with.

More correctly,one less meal to prepare for.

Intermittent fasting makes things simpler as you don’t have to plan, cook or wash dishes after so many meals. Just a few would do.


Intermittent fasting is a great way to keep your calorie intake in check. Once you always keep to the no binge rule.

If you’re doing it for weight loss, be sure to couple it with some exercises. As this would make your result faster and more obvious.

One of the great things about intermittent fasting is that along the line your body gets used to it. It becomes sort of your lifestyle. And you wouldn’t even need to think about it anymore, you just do it.