Type-2 Diabetes and Intermittent Fasting: Pros and Cons

Type-2 Diabetes and Intermittent Fasting: Pros and Cons
February 15 07:29 2021 by admin Print This Article

According to the International Diabetes Foundation, India is home to the second-highest number of diabetics in the world with 77 million people. China stands in first place with 116 million. Disposable incomes, sedentary lifestyle, and unhealthy eating habits have resulted in widespread obesity and Type-2 diabetes.

Type-2 diabetes is a condition in which the body cells have become resistant to insulin and are not able to convert sugar from the food we consume, into energy. As a result, blood sugar levels keep rising, and to beat the situation, insulin levels also keep rising. This creates various complications with time.

Medication, lifestyle changes, exercising, and other methods are helping people overcome the risks of Type-2 diabetes. One such method is Intermittent Fasting.

What is Intermittent Fasting (IF)?

Indians are familiar with the idea of fasting for reasons of faith. In this practice, on a specific day or days of a week, month or year, people abstain from food or water for 12 to 24 hours. Intermittent fasting goes a step further. In this method, the person avoids consuming food 2 or 3 days a week, for different durations of time ranging from 8 to 24 hours, but consumes water as usual.

Intermittent fasting has become popular in recent years with people trying to lose weight, and/or overcome Type-2 diabetes. While research is ongoing on the subject, the preliminary findings are encouraging. However, there are certain disadvantages too. So it’s important that people with Type-2 diabetes be aware of the pros and cons of intermittent fasting.

Types of Intermittent Fasting (IF)

While there can be different types of Intermittent Fasts, depending on duration and type of food abstained from, the most popular are:

  • 12/12 method: In this, you can fast for 12 hours and eat during the remaining 12 hours. This is something most people may already be following, as for example, if you finished breakfast at 9 am and dinner by 9 pm! A variation of this diet is 14:10 where you fast for 14 hours of the day and eat for 10 hours.
  • 16/8 method: As the name implies, you fast for 16 hours and eat during the other 8 hours. This is possible when one skips breakfast and has lunch and dinner spaced 8 hours apart. Or one has breakfast, lunch, and a late afternoon snack while skipping dinner.
  • 20/4 method: In this, you fast for 20 hours and can eat for the balance of four hours. This automatically implies you are having anyone meal only, in a day.
  • 5:2 Diet: In this method, you eat normally for 5 days of the week and follow a 24-hour fast for the remaining 2 days.
  • Eat stop eat: This is a variation of the 5:2 Diet where-in the 2 days of fasting in a week are not fixed and you can choose them at random.

Other types include Alternate-day fasting and the Warrior Diet.


According to research published by the Diabetes Council and other journals, there are various benefits of Intermittent Fasting for people with Type-2 diabetes and other ailments.

  • Weight Loss: Compared to low-calorie or other diet programs, Intermittent Fasting is more efficient in fat burning and fat loss. Excess fat in the pancreas and liver are also burnt over time, which aids in their proper functioning. Weight-loss reduces hemoglobin A1C level which is a measure of blood sugar levels over the last 3 months, and an indicator of either diabetes or pre-diabetes. With weight-loss comes reduced blood-pressure. People who maintain intermittent fasts have shown reduced bad cholesterol and increased good cholesterol levels. This in turn reduces the risk of heart attack and stroke.
  • Insulin sensitivity: Intermittent fasts bring about a reduction in visceral fat thereby improving insulin sensitivity in both obese and healthy individuals. IF is also known to reduce glycemic variability, which is – rapid swings in blood sugar levels over a day. People who maintain intermittent fasts also show a reduction in fasting and post-prandial blood sugar
  • Metabolic switching: After the body has converted the required amount of sugar from the food we consume into energy, the excess sugar still available is stored as glycogen in the liver and skeletal muscles. Similarly, excess fat from the food we consume is stored as triglycerides in adipose tissue, or what we call body fat. When a person is on an intermittent fast, the body is denied glucose that comes from food, so the body starts burning glycogen and body fat. The body is then said to have gone into a ketogenic state. Since there is no rise in blood sugar levels, insulin production also slows down. This has a healthy effect on the liver and pancreas.
  • Healthy Autophagy: Autophagy is a normal process by which old, damaged and dead cells in the body are routinely replaced with new ones. IF is known to improve autophagy. This goes a long way in reducing inflammation and the risk of cancer.


  • Hypo and Hyperglycemia: In some people, an Intermittent Fast can cause a drastic drop in blood sugar levels (hypoglycemia). This manifests as dizziness or light-headedness. The person may feel shaky or even faint. On the other hand, when people break an Intermittent fast with a heavy or high-carbohydrate meal, there can be a drastic rise in blood sugar levels (hyperglycemia). Repeated bouts of hypo or hyperglycemia can be dangerous and cause various complications.
  • Low energy and irritability: It takes a couple of weeks for people on an intermittent fast program to feel normal, healthy, or better. Till then, the person may experience low energy and irritability due to the changed schedules of eating.
  • Binge eating: The direct consequence of the above point is that people tend to binge eat during the eating period. This defeats the purpose and puts them at a higher level of risk than they were before starting the IF program.
  • Dehydration: During the fasting period, people tend to skip water along with the food. This is risky and leads to other complications. One should continue to consume the same amount of water every day, irrespective of an IF program or not.
  • Hormonal imbalance: IF increases the risk of hormonal imbalance in women. This can lead to late, early, and missed periods, as well as a polycystic ovarian syndrome (PCOS). Women trying to conceive can also find it hampered by such imbalances.
  • Acidic body: The stomach secretes gastric juice that helps in the process of digestion. The secretion happens whether one is fasting or not. In the absence of food in the stomach, the acidic gastric juice can attack the inner lining of the stomach. This causes acidity and stomach ulcers.
  • Heartburn, bloating, and constipation: The above condition can also lead to heartburn and a bloated feeling in the stomach. Further, since the intake of solid food is reduced during the IF program as one or more meal is skipped, fasters can experience constipation for a few days till the body adapts to the program. One way of overcoming these hassles is to drink adequate water.


From the above, it’s clear that the pros and cons of Intermittent Fasting are stacked equally against each other, for a person with Type-2 diabetes. If you are interested in starting an IF program but are not able to decide, consult a reputed hospital. Such hospitals have some of the best dieticians, nutritionists, diabetologists, and gastrointestinal specialists in town, on their rolls.

This article is available in audio format, click “Play” button to listen.

Kauvery Hospital is globally known for its multidisciplinary services at all its Centers of Excellence, and for its comprehensive, Avant-Grade technology, especially in diagnostics and remedial care in heart diseases, transplantation, vascular and neurosciences medicine. Located in the heart of Trichy (Tennur, Royal Road and Alexandria Road (Cantonment), Chennai, Hosur, Salem, Tirunelveli and Bengaluru, the hospital also renders adult and pediatric trauma care.

Chennai – 044 4000 6000 • Trichy – Cantonment – 0431 4077777 • Trichy – Heartcity – 0431 4003500 • Trichy – Tennur – 0431 4022555 • Hosur – 04344 272727 • Salem – 0427 2677777 • Tirunelveli – 0462 4006000 • Bengaluru – 080 6801 6801

write a comment


  1. Senthil Kumar
    February 20, 01:05 #1 Senthil Kumar

    Who knew the two could have been related in any way….Thank you for the info!

    Reply to this comment
  2. Kazi Asraf
    July 26, 15:43 #2 Kazi Asraf

    It’s a very informative site! Thank you for your share.

    Reply to this comment

Add a Comment

Your data will be safe! Your e-mail address will not be published. Other data you enter will not be shared with any third party.
All * fields are required.