• Intermittent fasting may help with weight loss, which can reduce the risk of diabetes complications.
  • While intermittent fasting can be done safely, people with diabetes may be at risk of hypoglycemia and hyperglycemia, due to fluctuations in blood sugar during and after periods of not eating.
  • More research is needed to determine the long-term risks and benefits of intermittent fasting for people with diabetes.

Intermittent fasting is a type of diet that involves limiting your meals to a certain window of time, followed by a fixed period of eating little or nothing. The fasting period can last anywhere from a few hours to multiple days.

Some research has shown that intermittent fasting may provide benefits for people with diabetes, such as weight loss. However, major adjustments in eating patterns could lead to swings in blood sugar levels, which can be dangerous.

So, is intermittent fasting safe for people with diabetes?

Read on to learn more about the potential benefits and risks of intermittent fasting with type 2 diabetes.

Intermittent fasting may present some risks for people with diabetes.

If you use insulin or medications and suddenly eat much less than normal, blood sugar can drop too low. This is called hypoglycemia.

According to the American Diabetes Association (ADA), hypoglycemia can lead to symptoms such as:

  • shakiness
  • confusion
  • irritability
  • rapid heartbeat
  • feeling nervous
  • sweating
  • chills
  • dizziness
  • sleepiness
  • low energy
  • blurred vision
  • nausea

Another potential danger of intermittent fasting with diabetes is high blood sugar. This is known as hyperglycemia.

Hyperglycemia can happen if you eat more than you typically do, which may be likely to occur if you’re especially hungry after a period of fasting.

High blood sugar levels can increase your risk of diabetes complications, such as:

  • nerve damage (neuropathy)
  • eye conditions and blindness
  • kidney disease
  • heart disease
  • stroke
  • high blood pressure

Before starting any diet or weight loss plan, consider meeting with a member of your diabetes care team, such as a physician or dietitian, to make sure it’s safe for you.

Some early research on animals shows that intermittent fasting may impact the pancreas and insulin resistance, but more studies are needed to determine its impact on diabetes in humans.

A 2020 study looked at what happened to rats when they fasted every other day for 12 weeks. It found that the rats had an increase in belly fat, damage to pancreas cells that release insulin, and signs of insulin resistance.

It’s important to note that the findings may be different if humans took part in the same experiment. More research is needed to determine whether intermittent fasting can increase the risk of diabetes in people.

It may be possible for intermittent fasting to put diabetes into remission for some people, perhaps due to weight loss.

A 2018 case report evaluated three people with type 2 diabetes who used insulin and fasted at least three times a week. Within a month, they no longer needed to use insulin.

They also had improvements in their body mass index (BMI), waist circumference, and HbA1C levels. After several months, the participants each lost about 10 percent of their body weight.

The sample size of that report was too small to make conclusions about how intermittent fasting can affect the majority of people with diabetes.

However, a larger study in 2018 found that nearly half of people with type 2 diabetes who lost weight were able to stop using diabetes medication and achieve remission.

Since intermittent fasting can be a way to cut calories, it may help people with diabetes lose weight and increase their likelihood of remission.

Other weight loss strategies may also help reverse diabetes, however.

Everyone is different, so what’s best for you may differ from what works best for someone else. Consult with a healthcare professional or dietitian to determine which strategy may be right for you.

Fasting is when you stop eating or drinking (or both) for a stretch of time. People may fast for a variety of reasons, such as:

  • as a religious practice
  • in preparation for a medical procedure
  • an attempt to lose weight
  • to improve health in some way

Intermittent fasting is an eating pattern that involves periods of eating little to no food, followed by regular meals. Unlike many other diets, it usually focuses on restricting the timing of when you eat and drink, rather than the foods on your plate.

Intermittent fasting is often used as a way to lose weight through calorie restriction. It may provide certain benefits for people with diabetes, but there are risks involved.

While intermittent fasting diets come in a variety of styles, no particular one has been proven best for people with diabetes.

Here are a few common intermittent fasting diets:

  • 16:8 intermittent fasting. People following this diet eat all meals within an 8-hour window, followed by 16 hours of fasting. Many people fast from 8 p.m. until noon the next day, and keep their eating window between noon and 8 p.m.
  • 5:2 intermittent fasting. This is when you eat regular meals for 5 days, then have 2 days of fasting, during which you eat fewer than 500 calories per day.
  • Alternate-day fasting. This is a full 24 hours without eating anything or only eating a small amount, followed by 24 hours of eating as usual.
  • Early time-restricted feeding (eTRF). This restricts your mealtimes to the morning and early afternoon, followed by a fast that lasts the rest of the day and night.

When done safely, intermittent fasting may provide some benefits for people with diabetes. If the eating plan leads to weight loss, people may be able to reduce the amount of diabetes medication they take.

Some people have been able to stop using insulin after fasting intermittently for a month or so, according to the small study on three people mentioned earlier.

More research is needed to determine if intermittent fasting can help most people with diabetes stop using insulin.

Other potential benefits include:

  • improved insulin sensitivity
  • lower blood pressure
  • lower oxidative stress
  • reduced appetite
  • increased fat oxidation

More research is needed to determine the long-term benefits of intermittent fasting on glucose control and diabetes complications, according to the ADA.

If you have diabetes and are thinking of trying intermittent fasting, here are some tips:

  • Talk with your healthcare provider about adjusting medication or insulin dosages. You may need to change your diabetes treatment when trying a diet that could affect your blood sugar levels.
  • Monitor your blood sugar levels. Long periods without eating can cause blood sugar to go too low, so check you glucose levels often.
  • Check in on your mood. Many people find that restricting food intake can really affect their mood. Watch for signs like irritability, increased anxiety, and difficulty coping with stress.
  • Monitor energy levels. Fasting can make you feel fatigued — something you might want to keep in mind if you’re driving or operating equipment.
  • Balance your carbohydrates. Your body breaks down carbohydrates into glucose, which can lead to a spike in blood sugar. When you’re not fasting, try to balance carbohydrates in your meals with vegetables and protein to avoid high blood sugar.

Intermittent fasting can be one way to lose weight, which may help you manage diabetes.

One case study showed that intermittent fasting helped a few people with diabetes stop using insulin. Still, more research is needed.

While intermittent fasting can be done safely, people with diabetes may be at risk of hypoglycemia and hyperglycemia, due to fluctuations in blood sugar during and after periods of not eating.

Work with a healthcare professional, a member of your diabetes care team, or a dietitian before starting any weight loss plan. They can help you lose weight safely and sustainably.