The Pros and Cons of Intermittent Fasting

The pros and cons of Intermittent Fasting (IF)

  • Nutrition and fitness can be a confusing topic for many people
  • IF has been known to give followers quick and fast weight loss
  • Eating every 3 hours has been shown to improve metabolism

Intermittent Fasting (or IF) has taken the dieting world by storm. This approach restricts food intake for a certain period of time, followed by period of eating all your meals in a limited time span. Most people fast for 16-24 hours at a time, followed by periods of eating.

Think of this as a feast and famine type of lifestyle. And everyone is different when it comes to IF. Some followers fast for 24 hours at a time, followed by 24 hours of eating, and others may fast between 8pm and 12pm the next day, leaving their window of “feasting” between 12pm and 8pm.

Most IF proponents encourage consuming healthy foods during these eating windows, whereas some followers have a “free for all” and binge on whatever they crave while they have the chance. The praises of IF have been touted all throughout the internet from fitness professionals and athletes.

But is it right for you?

Nutrition and fitness can be a confusing topic for many people, and you may need help discerning if a certain diet or lifestyle is right for you. Here are some pros and cons to the IF lifestyle coming from a dietitian’s standpoint. I hope these help you as you decide whether or not this lifestyle is right for you!


1. Less focus on food. If you tend to focus on food too much, are always thinking about your next meal, or wish you could just STOP the incessant chatter in your mind about what to eat, the IF lifestyle may work for you. Eating less often makes it less necessary to think about food and focus too much on overindulging. Intermittent fasting only allows you eat during certain windows of time, which  means those other hours can be spent doing everything and anything besides eating, which may be freeing for some people.

2. Gut rest. By giving your body a break between meals, your gut and digestive tract can take a break from constantly digesting food. If you are eating throughout the day and constantly munching on snacks or that office candy bowl, your GI can feel overstressed. So fasting for certain periods of time may improve the function of your gut and give it a much needed rest.

3. Fast results. IF has been known to give followers quick and fast weight loss. Limiting your food intake could in turn limit your caloric intake, thus creating a deficit and allowing fat loss to occur.


1. Disordered eating behaviors. If you have a history of disordered eating, the IF lifestyle could trigger some unhealthy habits such as restriction/binge cycles. The guilt and shame associated with overeating could make you hyperaware of your eating habits and could lead to some unhealthy thoughts around food. As with any lifestyle, everyone responds differently to restriction and strict plans in general, so it is best to be aware of your tendencies when it comes to your thoughts around food.

2. Slowed metabolism. The less we eat, the less fuel we give our metabolism, which can actually slow down our metabolism. If food is not being consumed, why would our metabolisms work? It would be unnecessary to rev up and get ready to burn food and fuel that does not exist. Eating every 3 hours has been shown to improve metabolism because your body is getting enough rest in between meals, but also eating enough throughout the day to cause the metabolism to fire up and burn.

3. Women beware. Intermittent fasting could be more dangerous for women, triggering insomnia and hormonal irregularities. This lifestyle can make women more insulin resistant, causing elevated blood sugars and more stress on the body. To top it off, hormonal balance for women is crucial, and is strongly linked to stress and nutrition. Therefore, following a diet that restricts food intake for such long periods of time could be detrimental to a woman’s hormones and metabolism.

Each body is unique, and what works for one person may not work for another. It is important to evaluate each new eating plan you may want to follow to make sure it is right for your lifestyle and your goals.

And of course, always consult with a doctor and dietitian before embarking on a new routine!

About the author

Tveen Verano [MPH, RD] is a registered dietitian nutritionist from Southern California. She is currently working as a renal dietitian and has a private practice as a registered dietitian and online wellness coach. Her passion for nutrition and real food drives her to keep up with current research and provide relevant and applicable information to the public to help stop the trend of obesity and provide vitality and health to everyone.