What is intermittent fasting?
Intermittent fasting is a new trendy eating style that focuses on meal timing. This eating approach will not only help lose weight but will also improve your overall health. The studies show that intermittent fasting can positively influence your body and brain and can even help live longer (6, 5). The main idea of this method is that you cycle between periods of fasting and eating. However, even though intermittent fasting is more about adjusting your meal schedule, one shouldn’t forget that consuming nutrient-rich foods is just as important. The researches show that even if the weekly caloric intake is the same, intermittent fasters still lose weight and gain health benefits compared to a non-faster.
How can intermittent fasting help you lose weight?
Most people decide to try intermittent fasting to achieve their weight loss goal (4). Actually, intermittent fasting is an excellent way not only to lose weight effectively but also to get healthier. How does it work? Everything is really simple. You start consuming fewer calories when following the fasting diet plan, which reduces your overall daily calorie intake. The drastic change in your nutrition causes important changes in your body that lead to weight loss.
When you are in the fasting mode, your body starts using stored body fat for energy instead of sugars from food. This way intermittent fasting helps optimize the release of insulin. The study shows that due to hormonal changes, a short-term fasting can boost the metabolic rate by 3.6–14% (3, 8). Lower insulin levels make stored body fat more accessible (1). Fasting leads to a decrease in insulin level that prevents extra fat storage and helps your body mobilize stored fat. So, keeping your insulin level low and steady is key to weight loss. This way, you can lose extra pounds in a healthy way.
Types of Intermittent Fasting
The first thing you should consider before trying it is a meal schedule you feel most comfortable with. Due to its popularity, nutritionists created a lot of different types of eating plans. All of them are effective, but it’s important to find out which one works best for you.
Daily Intermittent Fasting
This approach is supposed to be the most effective for women. You can start eating at 10 AM and start your fasting period from 8PM until 10 AM the next day. However, if you can’t leave without breakfast, then choose this method is probably not the best option for you.
Men get the best results following this 16:8 approach. You can eat whatever you want within an 8-hour eating window and fast for the remaining 16 hours. Typically, a fast period starts with your evening meal at around 8 P.M. until noon the next day. You can adjust your eating schedule, for example, you could eat all your meals within the time period of 11 AM and 7 PM. A frequently asked question is “How often should I do the 16:8 fasting?” This is a daily fasting diet plan, so you are expected to do it every day to see the weight loss results. Remember intermittent fasting is not a diet, it’s an eating pattern that should be a part of your lifestyle, implemented every day, the lifelong regardless method you choose.
This method involves 4 hours of eating and 20 hours of fasting. For instance, you can have your meals between 2:00 pm and 6:00 pm every day and fast for the other 20 hours. This way, you can have one or two small meals in your 4-hour eating gap.
Weekly Intermittent Fasting
If you are a newbie to the intermittent fasting, then this method will be the easiest one for you. This method is no that effective as daily intermittent fasting, however, you will also get plenty of benefits from it. This scheme is really simple. Typically, people who stick to this approach fast for 24 hours eating one time per day. This method can be used 2-3 times per week. For instance, you can start the fasting period at noon on Friday and have your first meal at noon on Sunday. This approach will help you to get used to this method. In fact, you skip around 2-3 meals per week, however, pay attention that this method won’t help you lose weight.
Alternate Day Intermittent Fasting
This method involves longer fasting periods. Usually, people go 24-36 hours without food, having one meal per day. However, the main disadvantage of this approach is that it’s quite challenging to get all essential nutrients at one meal. It requires a lot of cooking to get well-balanced nutrition. Moreover, it’s quite difficult to make yourself get adequate calories in one single meal, so a 24-hour period fasting is quite challenging for a dieter.
The main idea of this eating approach is that you have 5 regular eating days and 2 fasting days. You can eat up to 500 calories per day at any time during your fasting days. What to eat on fasting days? Make sure your ration is well-balanced and include protein, salad, fruits, and high-fiber foods. Do not try to fast 2 days in a row as it’s won’t be effective, try to separate them.
Benefits of Intermittent Fasting
- Stimulates brain function
- Boosts metabolism
- Helps prevent cancer
- Promotes weight loss
- Improves heart function
- Boosts the immune system
- Improves cholesterol and blood sugar levels
- Increases energy, focus, and mental clarity
What to eat during the fasting period?
This eating approach doesn’t have any specific food restriction, however, it’s better to stick to a well-balanced diet to get the best weight loss effect of the fasting. Make sure to eat high-fiber and high-protein foods to suppress your appetite during your fasting period. This can include nuts, beans, fruits, veggies, meat, fish or tofu. Note, consuming too many calories in your eating window can lead to weight gain, so make sure to track your calorie intake. Let’s take a closer look on what should be included into your daily ration.
- Veggies – a healthy diet should include high-fiber foods like broccoli, cauliflower, and Brussel. It will support your digestion and will make you feel fuller.
- Beans & Legumes – Black beans, chickpeas, and peas are a good source of protein that will boost your energy.
- Fruits & Berries – Track your daily fruit intake and avoid overeating them as they contain natural sugar that can increase your insulin level. Add more berries to your daily ration, you can add them to a salad or a dessert.
- Nuts – Nuts are full of healthy fats that will give you a feeling of satiety. Be careful, they are high in calories, so do not overeat them. You can eat a handful of almonds, walnuts, hazelnuts or cashews as a snack.
- Protein – Lean beef, chicken, eggs and seafood are excellent sources of protein. It will give you the feeling of fullness and will help build muscle mass.
- Seafood – Salmon, shrimp, and trout are the best nutrient-dense choices.
- Whole Grains – Barley, brown rice, buckwheat, bulgur, oatmeal are rich in protein and fiber.
- Healthy Fats – Nuts, seafood, olive oil, and coconut oil are the best sources of healthy fats.
- Dairy – There is no need to choose low-fat dairy, as they have fewer nutrients.
Foods to avoid while intermittent fasting:
- Fast Foods (chips, sandwiches, pitas, hamburgers, fried chicken, french fries, onion rings, chicken nuggets, tacos, pizza, hot dogs)
- Processed Foods (breakfast cereals, tinned vegetables, crisps, sausage rolls, bacon, sausage, ham, salami, ready meals)
- Simple Carbs (raw sugar, corn syrup, glucose, fructose, sucrose, fruit juice concentrate, etc.)
- Sweets (candies, lollipops, candy bars, chocolate, cotton candy, etc)
What to drink during intermittent fasting?
- Water. The idea of fasting seems to be quite challenging, no worries, just make sure to drink plenty of pure water, it will help you reduce hunger and appetite. Moreover, hydration increases fat burning process and boosts your metabolism, making you much closer to your weight loss goal. Another frequently asked question is “Can I drink lemon water during the fasting period?” Absolutely! Drinking lemon water is a good idea as lemon is rich in vitamin C, it will help you overcome the challenge during the fasting period giving the feeling of fullness.
- Coffee. Enjoy drinking coffee during the fasting period, it will not only help you stay alert but will also boost your metabolism promoting weight loss. However, make sure to avoid adding cream, milk or sugar to it.
- Tea. Drinking green tea will help you burn more fat and won’t break your fast. Like with coffee, do not add cream, milk or sugar into it.
- Bone Broth. Say “Yes” to drinking bone broth during the fasting period, it has anti-inflammatory and anti-aging properties, so it’s definitely a great idea! Moreover, bone broth improves skin health, hair, and nails, so it’s a super healthy beverage that should be included in your ration.
- Apple Cider Vinegar (ACV). Drinking apple cider vinegar is a good idea as it boosts metabolism, therefore, promotes weight loss.
- Stevia. If you can’t live without sweet taste, then stevia is for you. You can add stevia to your ration during the fasting as it contains no calories, however, be careful as it can trigger hunger in some people.
- Almond milk. Drinking up to 100 ml of almond milk won’t break your fasting and will give the feeling of satiety. However, make sure to read the labels before buying it as some products may contain sugar.
- (Diet) Sodas
How to manage hunger while intermittent fasting?
- Stay hydrated, drink pure water
- Eat a small amount on fast days
- Get a good night sleep
- Stay busy
- Drink coffee or tea
- Give yourself one month to see whether a specific approach of fasting is a good option for you
- Follow a low-carb diet during your eating window to reduce your hunger.
- Don’t binge after fasting
How to start intermittent fasting?
- Consult with your doctor before starting fasting
- Choose the best type of fasting for yourself
- Decide upon the length of the fasting period
- Start fasting. If any health issues appear, then stop right away.
- Stay busy and stick to a normal rhythm of life
- Break the fast gently
Mistakes to avoid while practicing intermittent fasting
Look through the list of the most common mistakes people do while fasting, this will help you to reach your weight loss goal much faster.
- Doing intensive workouts during the fasting period. Avoid high-intensity workouts on an empty stomach as it can be dangerous and doesn’t benefit your health. It’s better to choose a low-impact workout when you are fasting, like yoga or stretching.
- Eating whatever you want. Avoid eating unhealthy foods like chips, fried foods, and sweets as it will prevent you from reaching your weight loss goal and won’t bring you any health benefits. Make sure your ration includes fruits, vegetables, healthy fats, whole grains, and lean proteins when fasting.
- Not eating enough. There is no need to focus on cutting your calories even if you want to lose extra pounds. Instead of this, make sure to include nutritious foods during your eating windows. Avoid starvation as it is an ineffective way of weight loss, moreover, it can even lead to weight gain. Don’t forget that your body needs a sufficient amount of food so that your organs can function properly.
- Choosing the wrong plan for your lifestyle. There are different approaches to intermittent fasting and it’s extremely important to find the right one for yourself. Make sure to choose the fasting plan that works for your lifestyle to rich the best results.
- Dehydration. It can be one of the reasons you are not able to overcome the plateau, moreover, it can cause unpleasant symptoms like muscle cramps, headaches, and hunger pangs. Make sure to drink enough water throughout the day, it will give you a feeling of fullness, reduce food craving and boost your metabolism.
Intermittent Fasting FAQs
How much weight will I lose?
The weight loss results depend on many factors like nutrition, lifestyle, length, and frequency of fasting. Generally, however, healthy weight loss is 1-2 pounds a week. Keep in mind, that it is common to get a 4-5 pound weight loss during the first few weeks, but that is mainly due to losing water weight and usually that number will go down after the initial period. Moderate physical activity can facilitate the weight loss process so that you could get even better results. A 20-hour fast is considered to be the most successful method for weight loss. However, you will get fantastic results if you stick to a healthy eating plan and have regular workouts. Nevertheless, this fasting approach is difficult to stick to for a long period of time. The most popular fasting diet plan is 16:8, it is easy to follow and the weight loss results can be great as well.
Can I work out while fasting?
Absolutely! In fact, regular workouts will help you lose weight much faster, but it’s important to choose the right exercise program during the fasting period. You can do 3-4 full body workouts per week to burn fat more effectively. If you are fasting it’s better to do cardio low-intensity workouts. Make sure to listen to your body: if you feel dizzy, stop exercising. You can get back to high-intensity workouts only after you’ve eaten.
Does chewing gum break my fasting?
Experts state that chewing gum can potentially interfere with your fasting process, however, the amount of sugar is too low in it so that it makes no difference. Chewing gum can make a fasting period a bit easier. Still, if you see that you have no weight-loss results, it’s better to cut it out and if everything is ok and you see the progress, then continue. Besides, you could try following a no-sugar diet to improve your health even more.
How often should I do intermittent fasting?
There is no one right answer to this question as everything depends on your goal and lifestyle. Follow personalized fasting eating plan that you can stick to for a long time and you will get the best results. But be aware that a long-term fasting may lead to severe health problems (2).
How long should I do intermittent fasting to lose weight?
The fat burning results depend on many factors like your primary weight, nutrition, lifestyle, etc. However, if all rules are followed, you should stick to a fasting diet plan for at least 10 weeks to see the weight loss results.
Does intermittent fasting slow down metabolism?
The research shows that fasting for a short time can significantly increase the metabolic rate (3, 8). while another study found that fasting for more than 3 days can suppress the metabolism (7). However, the results of the studies are quite mixed, therefore, further research is needed on the fasting diet plan and its effect on metabolism.
Why am I not losing weight on intermittent fasting?
You should remember that intermittent fasting is not a magic pill that will make your body lose weight. It’s extremely important to stick to a healthy nutrition plan in your eating window, track your daily calorie intake, stay hydrated and avoid drinking “forbidden” beverages in the fasting period. Of course, there are plenty of reasons that may prevent you from losing weight like health issues, medications, lifestyle, etc. Don’t forget to pick a sport, physical activity will help you to overcome the plateau. Another important thing is to avoid starvation mode. Of course, you may feel hunger during the fasting period, however, make sure to feast in your eating windows.
If you want to speed up weight loss and tone your body, introduce some physical exercise into your lifestyle. Long walks, jogging, dancing or even a 20 Minute Full Body Workout at Home. Check out the video below.
How do I get enough calories in if I fast?
Try to stick to a well-balanced eating plan to get all essential vitamins, minerals, and nutrients that are important for the proper functioning of our body. But don’t forget to track your calorie intake not to overeat in your eating windows as it may lead to weight gain. The main point of fasting is to give your body rest from digestion, but it doesn’t mean you need to starve, find a balance. Try to add nutrient-dense foods adding nuts, seeds, grains, and fats to get the calories you need.
How to regulate blood glucose spikes and dips?
No worries, the fasting eating plan will improve sensitivity and your blood glucose response if all IF rules are followed.
This article is intended for general informational purposes only and does not address individual circumstances. It is not a substitute for professional advice or help and should not be relied on to make decisions of any kind. A licensed physician should be consulted for diagnosis and treatment of any medical conditions. Any action you take upon the information presented in this article is strictly at your own risk and responsibility!
- Alternate-day fasting in nonobese subjects: effects on body weight, body composition, and energy metabolism. (2005, ncbi.nlm.nih.gov)
- Are dietary patterns useful for understanding the role of diet in chronic disease? (2001, ncbi.nlm.nih.gov)
- Enhanced thermogenic response to epinephrine after 48-h starvation in humans (1990, ncbi.nlm.nih.gov)
- Fasting for weight loss: an effective strategy or latest dieting trend? (2015, ncbi.nlm.nih.gov)
- Fasting: Molecular Mechanisms and Clinical Applications (2014, ncbi.nlm.nih.gov)
- Intermittent fasting vs daily calorie restriction for type 2 diabetes prevention: a review of human findings (2014, sciencedirect.com)
- Leucine, glucose, and energy metabolism after 3 days of fasting in healthy human subjects (1987, ncbi.nlm.nih.gov)
- Resting energy expenditure in short-term starvation is increased as a result of an increase in serum norepinephrine (2000, ncbi.nlm.nih.gov)