Diabetes and Intermittent Fasting: Is It Safe and Effective?

INTRODUCTION:

Intermittent fasting (IF) is an eating regimen that cycles between periods of eating and voluntary fasting or significantly reduced calorie intake. Rather than focusing on what you eat, IF emphasizes when you eat, making it a popular strategy for improving metabolic health.

For people with diabetes, intermittent fasting holds the potential to improve blood glucose control and, in some cases, may even contribute to remission. However, it's essential to approach this method with caution, especially for those taking insulin or other glucose-lowering medications, as fasting can increase the risk of hypoglycaemia if not properly managed.

Researchers believe that intermittent fasting triggers a metabolic switch—shifting the body’s primary energy source from glucose to fat. This switch may enhance insulin sensitivity, reduce inflammation, and promote fat loss. In addition, IF may positively influence the circadian rhythms of gut biology and regulate the release of hormones such as insulin and growth hormone, all of which can support healthier energy metabolism and better weight management.

What Is Intermittent Fasting?

Intermittent fasting (IF) is a way of eating that includes regular periods where you either don’t eat at all or eat very little. While everyone naturally fasts overnight during sleep, people who follow intermittent fasting choose to extend this fasting time on purpose to gain health benefits.

People use intermittent fasting for different reasons—mainly to lose weight and to improve their overall health. It can help lower blood fat levels, cholesterol, and triglycerides, and it may also help control blood sugar and reduce HbA1c levels (average blood sugar control) over the last 3 months.

In traditional intermittent fasting, no calories are eaten during the fasting period. In some modified versions, a small amount of food is allowed—usually less than 25% of your normal calories.

There are several popular approaches to intermittent fasting, including:

• Time-restricted eating – limiting food intake to a specific window each day (e.g., 12 p.m. to 8 p.m.)
• Caloric restriction during fasting – consuming very few calories on designated fasting days
• Alternate-day fasting – rotating between days of normal eating and days of fasting or low-calorie intake

While the potential benefits are promising, intermittent fasting is not suitable for everyone. It should always be adopted under medical supervision, particularly for individuals managing chronic conditions like diabetes.

How Intermittent Fasting Can Affect Diabetes:

Intermittent fasting is a newer type of eating plan, and while it’s gaining popularity, we still need more research to fully understand how it affects people with diabetes.

Some early studies have been done, but there isn’t enough strong evidence yet to say for sure how helpful it is. It's also not clear if intermittent fasting works better than more traditional methods—like cutting calories every day (also known as continuous energy restriction).

A review from 2021 looked at five studies and found that both intermittent fasting and daily calorie restriction had similar effects for people with type 2 diabetes. Both methods helped improve blood sugar levels and A1C, which is a measure of your average blood sugar over the past three months.

Potential Benefits of Intermittent Fasting for People with Diabetes

If you follow intermittent fasting safely and with your health care /dietician guidance, it may offer several health benefits for people with diabetes. Research shows it can help people with both type 1 and type 2 diabetes in the following ways:

• Lowers blood sugar levels
• Helps your body break down fats more effectively
• Improves insulin sensitivity (your body doesn’t need to use as much insulin to control blood sugar)
• Supports weight loss and weight control
• Improves body composition (better balance of muscle, fat, and other body components)
• Reduces inflammation (which is linked to many health problems)
• Lowers blood pressure

Interestingly, intermittent fasting might also lower the risk of low blood sugar (hypoglycaemia) in people with type 1 diabetes.

The fact that intermittent fasting lowers your caloric intake is one of the reasons it can have such beneficial impacts. In addition to lowering blood sugar and blood lipid (fat) levels, this calorie reduction can aid in fat loss. People with diabetes may also benefit from intermittent fasting since it lowers insulin levels by allowing the body to meet energy needs by breaking down stored fat and glycogen, the kind of glucose that is stored in the body, but they should watch out for hypoglycemia.

Intermittent fasting may have long-term positive effects on type 2 diabetes. Participants who fasted for 18 hours three days a week for 12 weeks saw a substantial decrease in their HbA1C when compared to those who did not follow the diet, according to a 2023 randomized control trial that involved 46 individuals with type 2 diabetes on insulin. Among those who adhered to the regimen, no cases of dangerously low blood sugar were reported

Potential Downsides of Intermittent Fasting for People with Diabetes:

While intermittent fasting can have benefits, there are also some risks—especially if not done safely. Traditionally, people with diabetes are advised to eat regular meals to keep blood sugar stable. Fasting may cause:

• Dizziness from low blood sugar
• Headaches, a common side effect of fasting
• Extreme hunger, which can raise stress hormones and blood sugar
• Hormone changes, including insulin

For people with type 2 diabetes, fasting can be safe if medications are managed properly. But more research is needed before experts can fully recommend it.

For those with type 1 diabetes, fasting carries a higher risk of dangerously low blood sugar. This risk can be reduced by carefully checking blood sugar and adjusting medications.

Long fasting periods can also lead to dizziness, headaches, and hunger.

Always speak with your healthcare team before beginning intermittent fasting—what works for one person with diabetes may not work for another.

For diabetics who cannot do fasting, there is a plant based product called Moderate Sugar Slayer, that can help in reduction of post meal sugar spikes and help improve sensitivity when consumed regularly. It is a safe and effective product which has been tested in various clinical trials. One tablet before a carb or sugar rich meal is advised.

Conclusion:

Intermittent fasting can offer several health benefits for people with diabetes, especially for the obese and may help in better blood sugar control, improved insulin sensitivity, weight management, and reduced inflammation. However, it also comes with potential risks like low blood sugar, dizziness, and hormone imbalances—especially if not done under medical supervision.

The key to safe and effective intermittent fasting with diabetes lies in individualized care. It’s not a one-size-fits-all solution. What works for one person may not be safe for another.

If you’re considering intermittent fasting as part of your diabetes management plan, talk to your doctor or dietitian first. With proper guidance, monitoring, and adjustments to medication, fasting may be a helpful tool—but it should always be done with professional support.