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Is intermittent fasting safe?

By The Health News Team | April 23, 2024
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In recent years, intermittent fasting has been a popular method among people who want to lose weight or maintain a healthy weight. While many meal plans focus on what to eat, intermittent fasting is all about when you eat. When you intermittent fast, you eat during a specific time.

According to Jamie Degagne, a registered dietitian nutritionist for the Sharp Rees-Stealy Center for Health Management, intermittent fasting is an ancient practice followed in a variety of different formats. New ways of fasting add a fresh spin to this global practice.

According to Degagne, there are many different intermittent fasting schedules and ways to practice:

  • Daily time-restricted. Daily eating is restricted to one 6- or 8-hour period each day. For instance, you may choose to try 16:8 fasting, which is fasting for 16 hours and eating for eight hours. Since most people already fast for eight hours while sleeping, this method is easy to follow.

  • 5:2 fasting. The 5:2 approach, or alternate-day fasting, involves eating as you normally would five days a week and having a low calorie or no calorie day the other two days. However, this schedule can be dangerous for some people with certain conditions, and caution is recommended.

While fasting, you can drink water and zero-calorie beverages, such as black coffee and tea. And while eating, Degagne suggests, you should try to follow a balanced diet.

Benefits of intermittent fasting

Intermittent fasting is easy to follow, provides structure and doesn’t require calorie counting. It can reduce weight as effectively as decreasing the amount of calories consumed and can provide improvement in insulin resistance to help manage blood sugar levels.

Studies show that intermittent fasting can also improve conditions such as Type 2 diabetes, cardiovascular disease and cancer.

Drawbacks of intermittent fasting

Intermittent fasting is safe for many people but may lead to health risks for some. A recent study links intermittent fasting to increased heart health concerns. The study found that people who followed an eight-hour time-restricted eating schedule had a 91% higher risk of dying from cardiovascular disease compared to people who spread out their meals across 12 to 16 hours.

In addition, intermittent fasting isn’t recommended for individuals age 18 or younger, women who are pregnant or breastfeeding, people with Type 1 diabetes who use insulin, and people with a history of eating disorders.

Some side effects of the diet include:

  • Temperature sensitivity (often feeling cold)

  • Irritability

  • Having low energy

  • Difficulty concentrating

  • Increased hunger

Intermittent fasting can be an easy change to your routine, Degagne says, and a sustainable way to improve your health. However, it’s important to talk with your doctor before starting intermittent fasting.

Regular exercise, eating a plant-forward diet, staying hydrated and getting plenty of sleep can also help you reach and maintain a healthy weight.

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Jamie Degagne


Jamie Degagne is a registered dietitian nutritionist for the Sharp Rees-Stealy Center for Health Management.

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