How to Do 16/8 Intermittent Fasting

Fasting 16 hrs a day can help you get rid of belly fat forever. But the exact details of the fasting protocol make a huge difference. You need to be careful what and when you eat. Not to mention the meal composition.

There are many forms of intermittent fasting (IF). Some are more effective than others. Some may not work at all for you. It’s important to choose the right strategy based on your specific goals.

That’s why we’ve created this guide. It will help you begin the journey to your dream physique. Read on to find actionable steps with easy-to-understand explanations.

How Much Weight Can You Lose in a Month With IF?

A 200 lbs (overweight) individual can expect to be losing about 2 lbs fat a week. Some may lose up to 10 lbs in a single month. There are a few factors that determine your rate of weight loss.

starting body fat levels – the more fat you carry the faster the rate of fat loss
lifestyle and stress – other priorities in your life can reduce your ability to lose weight
training – different types of training can help you get lean faster

More aggressive forms of IF can easily backfire. Yes, you’ll lose more weight initially. But you’ll burn out quickly. There’s a risk of not only regaining but also putting on extra weight.

You should aim to lose about 1% of your body weight a week. The amount of weight lost each week will slowly decrease. At 250 lbs you can expect to lose 2.5 – 3 lbs a week. But once you pass the 200-pound mark, the rate will go down to 1.5 – 2 lbs a week.

Note: if you have less than 15 lbs to lose aim for 0.5% of body weight lost a week. Let's say your goal is to get from 175 to 160 lbs. The recommended weight loss rate is about 1 lb a week.

What’s the Difference Between Intermittent Fasting and Other Diets?

Almost all diets rely on creating a caloric deficit (consuming few calories). Any notable reduction in your daily intake will result in weight loss [1].

This is usually achieved by removing certain high-calorie foods from your diet. Examples may include chocolate, fried food, bread, soda, etc.

With fasting your goal is to limit the eating opportunities. Your food choices can remain the same. The typical IF protocol reduces your eating window to 8 hrs. The remaining 16 hrs you’re fasting.

You’ll tend to eat less due to limited food exposure. Hence the calories consumed are lower compared to your typical routine.

IF achieves the exact same result as other diets – weight loss because of reduced caloric intake. However, the major benefit of fasting is its simplicity. You don’t have to worry about food choices.

There’s only one rule – you’re not allowed to eat outside of the 8 hr eating window. It doesn’t get any simpler than this.

What Will Happen if You Fast for Longer than 16 hrs a Day?

You may not realize it, but you've been doing IF your whole life. Unless you suffer from insomnia, you’re not eating during the usual sleep hours. That means you’re fasting for at least 8 hrs at night.

Getting less sleep is bad for your waistline for many reasons. One of them is because you get less “fasting hours”. The time you’re exposed to food increases. So you’re more likely to overeat.

As already stated, calories are king. To lose weight you need to limit your intake. How exactly you do that doesn’t make a huge difference [2].

Reducing the number of meals, but making them too big may defeat the purpose of the fast. A single large meal can be so caloric that it's more than your usual intake.

Eating 1-2 very small meals is not a great idea either. It’s not a sustainable long term approach. You won't get enough sustenance to function properly.

A complete fast is the ultimate weight loss tool. But it has a very limited application. Full day fasts can only be implemented 1-2x a week.

Note: weight loss may stop at some point. This happens because your body adapted to your current intake. To keep losing fat decrease your calories again. That can be done by reducing meal sizes or removing snacks.

What Is The Best Approach?

How to start intermittent fasting:

keep meal composition relatively unchanged
don’t increase portion sizes
remove 1-2 of the main meals and all snacks
keep meal timings consistent during non-fasting hours
make sure the eating window synergizes well with your schedule

Some people make the mistake of eating less often but compensate by having bigger meals. Avoid that by keeping your meal composition unchanged after reducing the number of meals.

Note: sometimes changing your food choices may be a good idea. More on this at the end of the article.

You could also keep the same number of meals but make them smaller. Simply reduce portion sizes. But then again, you’ll have to eat 4-5 meals within an 8-hour window. Not a great use of your time.

Remember that IF allows for a lot of flexibility. You choose the length of the eating window. It can last 4 hrs or even up to 10 hrs. See what makes the most sense given your usual schedule.

The exact time of day when you fast also doesn’t matter much. If you prefer having breakfast, you’ll be better off fasting in the evening. But if you usually skip breakfast, morning is the ideal time for you to fast.

Lastly, avoid changing meal timings. Don’t eat your meals at 1 pm, 4 pm, and 7 pm one day. Then the next day go for 3 pm, 5 pm, and 9 pm. This will make managing hunger very hard.

Our bodies respond to routine. By being consistent you’ll avoid random hunger spikes. Have fixed meal timings. The body will learn to elevate hunger hormone production only around that time.

Learn our top IF tips from this 6 min video

Is There Any Research Done on Intermittent Fasting?

There are different types of fasting: full day, alternate day, intermittent fasting, etc. But they achieve the same result – reduced food intake. That, in turn, leads to notable weight loss [3].

The timing and length of the fast matter only within the context of food intake [4]. If the fasting period doesn’t result in a caloric deficit, you won’t lose weight.

The exact details of the specific fasting protocol have little significance. Eating 2 vs 3 meals makes little difference when calories are equated [5]. Same goes for fasting in the morning vs in the evening.

Note that some people may experience “negative” adaptations to fasting. Changes to their usual eating habits may result in suppressed activity levels or increased hunger. Such people may burn fewer calories, or be prone to overeat during the feeding window [6] [7] [8].

Is Fasting Good for Your Metabolism?

There are very few ways you can speed up your metabolism. But even if you manage to do that, it won’t result in any significant weight loss.

Fasting has almost no effect on your basal metabolic rate. But as already stated, it may change your (unconscious) activity levels.

Pay attention to your daily activity and hunger fluctuations. Let’s say you’re a habitual breakfast eater and tend to be active in the morning. If you decide to fast during the first part of the day you may struggle with hunger and experience energy crashes.

A better approach would be to open the eating window in the morning and fast in the evening. Experiment with different fasting protocols until you find what works for you.

Maybe you feel better keeping the fasting periods shorter. Or maybe you prefer doing alternate day fasting (full day fasts every other day).

There are plenty of strategies that work. Pick that one that best suits your lifestyle. As long as you bring down your caloric intake you’ll lose weight.

The IF Lifestyle: What to Eat?

There aren’t any specific food recommendations. Intermittent fasting is mostly about meal timing, not food choices.

However, hunger may become an issue for some people. This is when you need to be careful what you eat. Also, improving the quality of the diet can help speed up weight loss.

During the fasting period make sure you drink a lot of water. That will help reduce hunger. Note that most drinks (e.g. soda, alcohol, etc) have calories. Anything with calories is not allowed outside of the eating window.

When not fasting, go for low-calorie voluminous foods. This way you kill 2 birds with one stone. First, you increase your caloric deficit. Second, such foods take a long time to digest. This means you remain satiated long after the meal, past the end of the feeding window.