Pros and Cons of Intermittent Fasting

By Lizzie Streit, MS, RDN, LD 

Intermittent fasting, an eating pattern marked by periods of food restriction, is growing in popularity. Proponents claim it can accelerate weight loss and reduce the risk of chronic diseases, while others suggest it has no unique benefits. 

You may be wondering about the pros and cons of intermittent fasting. Read on to learn more about this popular eating pattern. 

What is intermittent fasting? 

Intermittent fasting is a general term used to describe the technique of switching between periods of fasting and eating.  

Here are the most common types of intermittent fasting: 

  • Fasting for 16 hours followed by eating during an 8-hour period, such as between the hours of 1 and 9 pm (the 16/8 method) 

  • Restricting calorie intake to about 500 calories on 2 days a week and eating normally on the other 5 days (the 5/2 method) 

  • Completely restricting all food intake for 24 hours, once or twice a week, and eating normally on the other days 

Possible Benefits 

Since intermittent fasting involves periods of food restriction, it can theoretically help with weight loss. If someone who practices intermitting fasting consumes fewer calories than they need per day, they may lose weight. But whether intermittent fasting is more effective for weight loss than other calorie-restricted diets remains to be seen. 

While some studies show that intermittent fasting may lead to more weight loss than other techniques, other research suggests otherwise. Some people find intermittent fasting especially appealing since it does not involve calorie counting. With no rules about tracking intake or limiting certain foods, adhering to intermittent fasting may be easier than sticking to other diets. 

Some of the other purported benefits of intermittent fasting include improved blood sugar controlreduced inflammationanti-cancer effects, and protection against heart disease. However, research on these benefits is limited and has mostly been conducted in animals or in small human trials. 

Possible Downsides 

There are also many downsides to intermittent fasting. For one, it may not be helpful for overall calorie restriction. Fasting for 16 hours or a full 24 hours can lead to hunger and subsequent overeating, which in turn may hinder weight loss or even lead to weight gain. It can also lead to low blood sugar, accompanied by nausea, fatigue, or dizziness, even if you don’t have issues with blood sugar. 

If you need a steady supply of energy throughout the day, you should also think twice about intermittent fasting. It’s not appropriate for pregnant or breastfeeding women, children, teenagers, individuals with diabetes, and those who struggle with disordered eating. Athletes and active people, especially those who exercise in the morning, might not fare well with intermittent fasting. 

Overall, the research on intermittent fasting is still limited. While it may work for some people, it’s not a good choice for others. Eating a balanced diet with nutritious foods that does not exceed your energy needs is effective for maintaining a healthy weight. 

Note from Healthy For Life Meals: Instead of focusing on the latest trend, we provide a science-based, healthy weight loss meal plan that will help you stick to healthy eating. Check out our menus and get started with your meal delivery service today.

Stef Keegan