Q: I want to lose 20 pounds before my son’s bar mitzvah in 3 months. I heard that intermittent fasting really works and will help me lose weight quickly. What exactly is intermittent fasting, and how do I do it?
A: Whoa, hold on! You didn’t ask me if I think intermittent fasting actually works or is even a good idea! This dieting method has been in the news a lot lately, with people telling stories of dramatic weight loss and improvements in metabolic conditions like diabetes. Let’s take a step back and look at it objectively.
There are a few forms of intermittent fasting. One type is alternate-day fasting, when a person fasts every other day. Another version is the 16:8 method, in which a person only eats for a set 8-hour period every day. Alternatively, some try the 5:2 method, in which a person eats only a small portion of their calorie needs on 2 nonconsecutive days of the week (the fasting days).
From a scientific standpoint, there is some evidence that it does work in the short term—people lose weight when they practice intermittent fasting. Yet, on average, this weight loss is not necessarily any greater than what occurs when someone decreases calorie intake on a daily basis. Additionally, due to many factors, including the difficulty of adhering to intermittent fasting, there is not much evidence that people can maintain the weight they lost while practicing intermittent fasting. This leads to another concern—weight cycling. Continuously losing and regaining weight is bad for us. It can lead to metabolic issues, such as diabetes, and it often results in higher body weight than one had before the weight cycling.
I have not yet met anyone who has been following this diet for years and is happy with it. I also mean happy with their eating experiences, and not just happy with their weight. Food is not only meant to fuel us. It is also an important way we have pleasure every day. Eating should be enjoyable, and avoiding eating can turn into an unpleasant task. We all know that not eating leads to cravings and can make us feel deprived. Unfortunately, when eating becomes about how we look, we are on a path to unhealthy body perceptions. At the end of the day, there is more to health than a number on a scale.
Here’s the deal: If someone can stick to intermittent fasting long-term, I would imagine she would lose weight and may maintain a new lower weight, but I can’t vouch for the long-term safety of this approach. Most importantly, I do not think it will lead to a better outlook on food, health, and our bodies.
A good alternative to intermittent fasting is being mindful of what you eat, which is the first step in improving how you eat. I would suggest starting a food diary in which you write down what you eat, how much, when, and your mood at the time. Doing this allows you to see what you are eating during your day in a more objective way than just trying to remember after the fact. You might be surprised with what you find there. Once you actually know what and how you are eating, you may notice areas where you can make healthy changes.