According to the dictionary, fasting is abstaining from all or some kinds of food or drink. But more accurately, fasting is a tool that can help you tap into your body’s innate healing and fat-burning potential by selectively refraining from caloric-food or drinks either part or all of the day.

Fasting has been part of every human culture and religion since time immemorial and is generally recognized by the medical establishment as being safe. There have even been yearlong fasts (doctor-supervised, of course) that were not damaging in any way!

But there are certain conditions that people should always check in with their doctors before attempting fasts of any kind:

• Heart problems
• Liver or kidney insufficiency
• Epilepsy
• Pregnancy or breast-feeding
• Eating disorders
• Hypothyroidism

Doctors regard most fasting methods as lifestyle changes – not a diet.

When you practice intermittent fasting, there are no limits as to what type of foods you can eat, and you can eat as much or as little as you need to during your eating window. (Active people usually have to eat more, and sedentary people are advised not to overeat on any fasting protocol.)

That said, most people tend to eat fewer calories while fasting as a lifestyle.

Researchers have focused mainly on alternate day fasts (also called Eat-Stop-Eat) and Time Restricted Eating. But the 16/8 method, the 5:2 method, and the fasting-mimicking diet are popularly used for weight loss and health gains.

What’s the best fasting method? That depends on your current state of health, your activity levels, and your calorie needs. Make sure to consult your doctor to see which one is right for you.

There isn’t just one way that fasting helps you lose weight, but we’ll start with the most obvious: you’re not eating.

Studies show that calorie restriction is one of the most reliable ways to lose weight and keep it off, and that’s true whether you cut portions daily or fast weekly.

Fasting also primes your metabolism to burn fat for fuel, which gives you energy and focus without the daily carb cravings.

Last but not least, fasting improves insulin sensitivity – this helps you lose weight in several ways