Intermittent fasting (IF) does not require counting calories, but you will not have the desired benefits if you overeat during non-fasting periods
Intermittent fasting (IF) does not require counting calories, but you will not have the desired benefits if you overeat during non-fasting periods.
If one of your goals of IF is to lose weight, you will need to restrict your calorie intake to be lower than the standard daily calorie limit according to your age, gender, size, and overall health.
What is intermittent fasting?
Intermittent fasting (IF) is the practice of fasting for a set amount of hours each day, followed by a window of time in which you are permitted to eat.
During the fasting period, you need to avoid solid foods and limit your diet to calorie-free beverages like water, coffee, and unsweetened teas. During the eating window, you can consume solid foods but are encouraged to follow a balanced diet and avoid junk foods.
While not a weight loss strategy, intermittent fasting may result in weight loss if you consume fewer calories than you are using for energy.
Some people find it helpful to follow the Mediterranean diet while doing intermittent fasting to ensure that they are getting enough nutrients during their eating window. The Mediterranean diet emphasizes whole grains, fruits, vegetables, lean proteins, seafood, and healthy fats.
What happens to your body during IF?
Fasting for a period of at least 12 hours alters the way your metabolic system functions. Your metabolic system is the process through which your body converts food into energy. Normally, your body obtains its energy from glucose, which is found in foods and beverages you consume. When you eat three meals a day, your body maintains a constant glucose level.
When you fast for more than 12 hours, your glucose levels begin to drop because you aren't eating as frequently. When your body lacks glucose, it burns fat for fuel. Fatty acids enter into your bloodstream and produce ketones, which are used as an energy source by your body. This is called a metabolic switch, in which your body converts glucose to ketones.
In order to reap the benefits of intermittent fasting, you need to fast for at least 12 consecutive hours because that is how long it takes for your body to go from using glucose to using fat for energy.
Since it may take some time for your body to adjust to a new eating regimen, results may not be immediate but take 2-4 weeks to be noticeable.
4 ways to do intermittent fasting
There are various methods to follow an intermittent fasting (IF) schedule:
- 5:2 method: This method focuses on limiting calories to 500 for 2 days, followed by a normal eating routine for the other 5 days of the week. When fasting, focusing on high-fiber and high-protein foods can help you feel full while keeping your calorie intake low. Consume the same amount of food that you would on non-fasting days.
- 16:18 method: With this method, you fast for 16 hours followed by an eating window of 8 hours, preferably between 11 am and 7 pm.
- 14:10 method: This involves fasting for 14 hours followed by an eating window of 10 hours, preferably between 10 am and 8 pm. Both 16:8 or 14:10 methods can be done twice a week, on alternate days, or every day.
- 24-hour fast: This method requires fasting for a full 24 hours 1-2 times a week and then resuming a normal diet on non-fasting days. However, this method of intermittent fasting may have severe side effects, including fatigue, headache, irritability, hunger, and low energy.