Does Intermittent Fasting Work?

You may have heard about various celebrity diets. Lately, it seems like everyone is into intermittent fasting. Should you try it too?

For most people, the answer is no.


Who Should Try It?

If you’re eating more than one meal per sitting. For example, if you go out to eat dinner and eat two entrees where everyone else is having one. There are some exceptions to this. For example, if you’re very tall, you may need the extra calories.  Otherwise, you could be having trouble losing weight because you’re eating too many calories. If that’s true, you may need to consider calorie restriction in addition to changing the composition of what you eat.

A recent study in the The Journal of the American Medical Association showed that weight loss from intermittent fasting is about the same as weight loss from calorie restriction. Although the study showed the fasting group had a higher dropout rate (38%) it was a small study (100 people). So you could still consider trying it. You may find that intermittent fasting is easier for you than calorie restriction.

If you try fasting you should watch out for signs of hypoglycemia (low blood sugar). You may have symptoms including but not limited to dizziness, anxiety, and even passing out. So be careful.


Who Shouldn’t Try It

Everyone else who is not eating multiple entrees per meal. In this case, fasting is the same thing as calorie restriction. If you’re eating a healthy amount of calories, it’s more efficient to change the composition of what you eat to lose weight and get fit.

The problem with calorie restriction and intermittent fasting is that you’ll lose weight initially, but your weight loss will eventually plateau. This is because you’ll reset your body to think it now needs a lower calorie intake. This lower calorie intake will eventually become your new normal. When it does, your weight loss will plateau.  If you then try to start eating the standard three regular sized meals a day again, you’ll probably put on weight pretty quickly. This can be frustrating for you and derail your whole getting fit mindset.


Your Diet Can Help Prevent Heart Disease and Cancer

Recently I was talking to a fellow doctor who said he was trying intermittent fasting by skipping lunch. He said, “because really what does a salad add anyways, it’s just lettuce and tomatoes.”

The answer is if you’re fasting or calorie restricting by cutting out fruits and vegetables, you won’t be getting the benefits of the antioxidants, vitamins, and minerals they contain. They have many benefits including potentially helping you prevent heart disease and cancer.

You could take pills to get vitamins, minerals, and antioxidants. But studies to do date show you’re more likely to get the benefits of antioxidants, vitamins, and minerals if you eat them in foods. One theory on why is that your body may not absorb and process vitamins, minerals, and antioxidants the same if they come from a pill as if they come from food.


In the end, for most of you, the best option for losing weight is changing the composition of what you eat.