16-hour fasting, Popularly known as intermittent fasting in the West, has been widely accepted by people worldwide.
You may think of intermittent fasting as a new fad diet, but did you know that what appears to be new isn’t new at all. 
Today, the fasting we believe to be a fad has actually been practiced by our ancestors for thousands of years. Many of our Shastras also clearly mention not to eat after sunset and in the morning until the sun has reached its peak.
Our ancestors didn’t name it 16-hour fasting or intermittent fasting but their daily lifestyle was such that they were following it automatically.
Today thousands of scientific studies are also proving that you can get so many benefits by giving your body a break from food daily.
Let us take a look at some of the amazing benefits of 16-hour fasting and everything around them.
What is 16-hour fasting?
Intermittent fasting is not a diet but an eating pattern in which there is a window where you can eat and there is a window where you have to fast.
There are a lot of versions of intermittent fasting but the most common and practiced one is the 16:8 method. In this method, you have to keep a fast for 16 hours where ideally you should not consume anything except water and coconut water and then comes the 8-hour window where you have to eat. In this 8 hour, you have to finish your breakfast, lunch and dinner.
Now, you are free to choose the 8-hour window according to your convenience.
It could be from
- 9 AM to 5 PM
- 10 AM to 7 PM
- 12 Noon to 8 PM
- 2 PM to 10 PM
So you are absolutely free to choose the window according to you.
How does 16-hour fasting work?
This 16-hour fast acts as a shock for your body. When you do intermittent fasting, there are a lot of hormonal changes in the body which help you effectively lose body fat. 
Intermittent fasting refers to eating plans that alternate between fasting and eating periods. The goal is to systematically starve the body long enough to trigger fat burning. While research is still underway and the method may not be suitable for everyone, there is evidence that, when done correctly, intermittent fasting can help lose weight, lower blood pressure and cholesterol, prevent or control diabetes, reduce the risk of cancer and improve the brain’s health. [3, 4]
During a meal, carbohydrates in food are broken down into glucose. Glucose absorbs through the intestinal wall into the bloodstream and is transported to various organs, where it serves as the major energy source. Excess glucose is stored for later use in the liver and adipose tissue, in the form of glycogen and fats. In between meals, when the body is in the fasted state, the liver converts glycogen back to glucose to keep supplying the body with energy. Typically, an inactive person takes about 10 to 12-hour to use up the glycogen stores, although someone who exercises may do so in much less time. Once the reserve of glycogen in the liver is depleted, the body taps into energy stores in adipose tissues. This is when fats are broken down into free fatty acids which are then converted into additional metabolic fuel in the liver. Thus, if the fasted state lasts long enough, the body burns fat for energy and loses that extra fat. Losing the extra fat is translated into a range of associated health benefits.
16-hour fasting diet
Break your fast with fruits or so something light. Then in the 8-hour window, have 3-4 meals.
Keep your meals high in protein, well balanced with complex carbohydrates, healthy fats, vitamins and minerals.
5 benefits of 16-hour fasting
- Relief to your organs
Imagine you’re working in the office and your boss keeps handing you more and more work. You keep working till the evening, and just as you’re about to get up, your boss hands you 3 more hours of work then as you’re about to get up and go home, he hands you 3 more hours of work.
What do you think? How long will you be able to work like this?
Now compare this situation with your digestive system.
Yes, You’re doing the same thing to your stomach.
You’re putting non-stop pressure on it. Before we’re able to digest last night’s dinner, we stuff breakfast in the morning. Before we digest that, we stuff our lunch on top of it.
To digest all this, your stomach ends up working 24 hours. It works overtime on most days. Without getting any off.
Think about it – how long will it be able to do this?
If you put so much pressure on it, soon it will stop functioning efficiently. The food you’ve eaten won’t get digested that easily.
This undigested food will keep accumulating inside and give birth to all kinds of diseases but with 16-hour fasting, we give a break to our stomach not just our stomach, all our other organs get a break too. Pancreas gets a break from producing insulin, the liver gets a break from making bile and the stomach gets a break from producing digestive juices. 
- More productivity
Let’s understand with this example, what happens when you use a heavy application on your phone continuously for 4-5 hours?
The battery of your phone drops down heavily and there’s no power left to use other apps.
In the same way, the heaviest app of your body is the app of digestion.
When you eat heavy foods without giving a break all day long, most of your energy will be used up by your digestion.
Do you know how much energy?
More than 70%!
Now if 70% energy has been spent here already, will you have any energy left for other activities?
Of course not and then you will start procrastinating things leading to decreased productivity.
- Proper absorption of nutrients
If you don’t keep your stomach empty for some time, then no matter how healthy you eat, no matter how many green veggies, juices, fruits and nuts you consume, it’s not going to help at all.
But with fasting, your stomach is emptied, so if you truly want to take in the nutrients of your food, then give your stomach a break every day.
Giving it a break creates space inside and then whatever you eat, your body will be able to absorb its nutrients properly. 
- Increase your human growth hormone by 5 times
There are various studies which shows that fasting increase growth hormone. Now, there are a lot of advantages of a high Human Growth Hormone.
The most important of all is that it increases your metabolism. And the higher metabolism you will have, the faster will be your fat loss process.
- Increases lifespan
There have been no studies done on humans as yet. However, scientists feel that humans would also get the same benefit.
3 ways to double its benefits
- Detox juice
In the morning, 2 hours before breaking your fast, take any vegetable juice – like ash gourd, bottle gourd, cucumber or coconut water.
When you’re fasting, your body is getting cleaned, the toxins accumulated inside start to leave your body. This detox juice acts as a catalyst and makes the cleaning process faster.
Avoid drinking tea, coffee, soup or smoothies.
- Have dinner before 7 PM
There’s a deep relationship between our digestive fire and the sun. When the sun is at its peak, our digestive fire is at its peak too and as the sun sets, our digestive fire goes down. 
So if you’re eating late at night, you won’t get its full benefit.
Eat as early as possible in the evening.
- Eat healthy
Fasting for 16 hours doesn’t mean you can eat anything. Breaking your fast with heavy and unhealthy food won’t help at all. To maximise the potential benefits, it is recommended that you eat only home-cooked food during the eating window.
Drawbacks of 16-hour fasting
Restricting your intake to just eight hours per day can cause some people to eat more than usual during the eating window to make up for the hour spent fasting.
This can result in digestive problems, bloating, weight gain and the development of unhealthy eating habits.
- Short term side effects
In the first week of starting intermittent fasting, you may feel low on energy, weak and fatigued. But don’t worry these side effects will gradually subside with time.
- Effects on reproductive health
In a study done on animals, it was reported that Intermittent fasting could interfere with fertility and reproductions in females.
However, more human studies are needed to evaluate the negative effects that intermittent fasting may have on reproductive health.
Who should not do 16-hour fasting?
You should not do intermittent fasting
- If you are trying to get pregnant
- If you are already pregnant
- If you are breastfeeding
- If you are below 18 years of age
- If you have eating disorders like bulimia or anorexia
The bottom line
Intermittent fasting is a completely safe way of eating. Start only if you are able to practice it for the long term.
The long term is important here. Because there is no point in doing IF for 2 weeks.
Your weight will drop and then you come back to the same position.
Also, ask yourself you have to keep a fast for 16 hours.
Are you prepared for it?
Because there are a group of people who find it very difficult to get adapt to it and then there are a group of people who say, it takes hardly 2-3 days to get used to it.
So do what you enjoy and what best fits your lifestyle and preferences.
It’s best to talk to your doctor before trying intermittent fasting, especially if you are on medication or have any health conditions.
Shecontent has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations.
- The Tribune- https://www.tribuneindia.com/news/health/intermittent-fasting-new-fad-among-millennial-young-adults-in-india-195054
- Healthline- https://www.healthline.com/nutrition/intermittent-fasting-and-weight-loss#hormonal-effects
- Harvard Health Publishing- https://www.health.harvard.edu/blog/intermittent-fasting-surprising-update-2018062914156
- Chigago Tribune
- Dylan Hughes- https://dylanhughes.medium.com/how-intermittent-fasting-can-make-you-more-productive-1f7974c109b7
- The Health Site
- Inside Tracker- https://blog.insidetracker.com/intermittent-fasting-impacts-longevity-summary-research#:~:text=During%20fasting%2C%20cells%20undergo%20an,including%20diabetes%20and%20cardiovascular%20disease.
16. Tattva Gyan
Frequently asked questions
We’ve started 16 hour-fasting, but we faced acidity, headache, tiredness, what do we do?
When you start 16-hour fasting, you should give your body some time to adjust if you’ve never done this before, initially you may face acidity, headache, or weakness but they’re temporary they’ll fade away within 2-4 days. Just be patient, If you face acidity, headache, or weakness, then you should increase the amount of water you drink during the 16-hour gap, keep sipping some water from time to time.
How long should we do 16-hour fasting?
Follow it for as long as you wish to be healthy. Maybe right now you’re thinking that you have to go out of your way to do it but soon, this will become a part of your lifestyle you won’t even feel like eating anything before 16 hours. Don’t follow it like a diet plan.
Should my fasting window remain the same every day? Or can I fast for different hours during different days too?
As much as possible, try to maintain the fasting window you follow every day so that your body gets used to those timings but I know it’s not always possible to maintain it. So it is okay but try to follow the same schedule every day.
I reach home by 8-9 PM. What do we do?
In this case, you can fast on weekdays for 14-hour instead of 16-hour. Even if you eat at 9 PM, eat breakfast only at 11 AM the next day.
And on weekends, to make up for it, you can fast the whole day.
Is fasting for 16 hours every day safe?
Intermittent fasting is a completely safe way of eating. several scientific studies prove its benefits.
However, you should avoid intermittent fasting
1. If you are trying to get pregnant
2. If you are already pregnant
3. If you are breastfeeding
4. If you are below 18 years of age
5. If you have eating disorders like bulimia or anorexia