Why does intermittent fasting work for type 2 diabetes? – Diabetes Doctor

Why does intermittent fasting work for type 2 diabetes?

Intermittent fasting has gotten a lot of attention recently for its proposed benefits on weight loss and, now, type 2 diabetes.  Many diabetes experts recommend following a low carbohydrate high fat (LCHF) diet. Since fat doesn’t need insulin to metabolize (like carbohydrates and even proteins do), it does not impact blood sugars or cause an insulin surge in the body.  But when calorie restriction, cutting portions and following an LCHF diet just isn’t enough – you may consider talking with your doctor about intermittent fasting. Some people are calling this the “cure for Type 2 Diabetes.”  

What is intermittent fasting?

Fasting means going a certain period of time without eating at all. The most popular methods are:

  • Alternate Day Fasting: A "fast day" of 24 hours is alternated with a day of regular food intake.
  • 5:2 Method: 2 non-consecutive days out of the week are considered "fast days", 5 days of the week are regular food intake.
  • 16:8 Method: All daily calories are eaten within an 8-hour window that you choose, but nothing is eaten the other 16 hours in the day. For example, many people skip breakfast and only eat during an 8-hour window such as 11 a.m. to 7 p.m. This method tends to be the most popular and most successful because it seems to be more manageable for most people than going 24+ hours without eating.  The rules are simple – don’t eat outside of the 8 hour window!

 Intermittent Fasting

During the fasting period, you can drink water, coffee, tea, or bone broth but should restrict total daily calories to < 500.

Much more than restricting calories…

A recent study shows people who followed an alternate-day fasting diet cut weekly calories by an average of 37% and lost an average of 7.7 pounds over four weeks, while those not on the diet reduced calories an average of 8.2% and lost an average of 0.44 pounds.  However, it should be understood that intermittent fasting is different than just cutting calories on a daily basis and has benefits beyond weight loss. 

It would be assumed that intermittent fasting only works because you are restricting the total amount of calories you are eating… although this may help, it is not the only piece of the puzzle. The key here is how often you eat, not the total number of calories you eat. Going long periods without eating at all versus eating a small amount more frequently induces a different metabolic and hormonal response by the body.  

Metabolic response:  Regularly cutting calories cause a decrease in the body’s metabolic rate … to counteract weight loss efforts! So eating less just means your metabolism slows down so it doesn’t burn as many calories – making weight loss quite literally impossible.  Additionally, people are left feeling cold, tired, and hungry.

What about intermittent fasting? “Wouldn’t this make my metabolism go to ZERO?” Actually, no! Some studies show metabolism actually slightly INCREASES during a period of fasting. Other studies show there is no decrease/no change in metabolic rate after 22 days of alternate daily fasting. During fasting, the body first burns off glycogen (i.e. stored sugar) in the liver, and then turns to burn fat. Since there is plenty of fat to burn, the body’s metabolic rate doesn’t drop.  Also, since there is no change in metabolic rate with intermittent fasting, there is also a low risk for rebound weight gain.

 Hormonal changes: Remember that type 2 diabetes is a disease of hyperinsulinemia (i.e. too much insulin!) – so the goal should be to lower insulin levels in the body as much as possible!   Intermittent fasting provides extended periods of low insulin to enhance insulin sensitivity and lowers insulin maximally compared to any other diet. 

Studies show that you may be able to lose the same amount of weight with intermittent fasting as restricting calories … but intermittent fasting is more effective at reducing insulin levels, reversing diabetes, and reducing the amount of fat inside the liver and pancreas organs. You can’t have a constant intake of food to get this same effect – despite decreasing carbs and calories.

With intermittent fasting, insulin levels drop sharply, noradrenaline rises to keep metabolism high, and growth hormone rises to maintain lean muscle mass. Recent studies also show a reduction in inflammation levels.

How long does it take to work?

Weight loss can start to occur quickly in the first few days.  If you are looking for diabetes remission and reduction in medications - usually people see results within weeks, but keep in mind it could take several months depending on the intensity of the fasting regimen and length of time you have had diabetes.

What do I eat during non-fasting periods?

Keep in mind, the more you eat insulin stimulating food (carbs/sugar/processed foods), the more you need to fast to bring those insulin levels back down. So it is recommended to follow LCHF during non-fasting times for maximum benefits.  In other words – you can’t binge for 8 hours and expect great results!

How should I expect to feel?

As the body starts to eliminate its stored sources of sugar (in the blood and organs) – people may experience initial hunger pains, headaches, and muscle cramping as it “detoxes”.  As insulin levels drop, this triggers the liver to release stored sugar and some people may notice an initial rise in blood sugar levels as this happens. Remember if the sugar is not coming from food, it is coming from somewhere else in the body (i.e. shifting locations to the blood!) and generally means a longer fast is needed (such as more hours fasting or more frequent days fasting).  If you aren’t replenishing the liver with sugar in between fasts, over time the stored sugar sources should eventually deplete themselves.

What do I do with my medications?

Fasting for a person with diabetes can be potentially dangerous and requires medical supervision.  You must talk with your healthcare provider for guidance with medication adjustments.  Risk of hypoglycemia with certain medications can be extremely dangerous (especially with insulin and sulfonylureas like glipizide and glimepiride) and certain medications such as SGLT2 inhibitors (Invokana, Farxiga, Jardiance, Steglatro) should absolutely not be taken during long fasting periods. 

How can Diabetes Doctor™ products help?

It is recommended to use Daily Support and Sugar-Blocker for support during intermittent fasting regimens.  Daily Support™ reduces insulin resistance, which helps reduce insulin levels.  Sugar-Blocker can be taken with meals on non-fasting days to reduce the number of carbohydrates absorbed with food. It can also be taken during fasting periods to suppress sugar cravings. Berberine, the key ingredient in Sugar-Blocker, is a powerful insulin sensitizer and has been shown to lower insulin levels.  


  • Chávez Socorro

    Tengo tipo 2 .
    Diabética. Quiero pastillaz me interesa y cuanto valen

  • Maria

    I was diagnosed in 2008 and I have been in denial; however I made better choices with my food. Got my weight down from 222 to 170. I am now 165. I recently got a checkup- no kidney damage! I am recommited to my health. I am walking a mile a day! I have gotten my blood sugar down but it has to be better! I am taking Metformin-ugh! I have been logging everything for about a week. I saw this ad for this natural product and I am about to order. I hate doing it omline. Thank you!

  • Marleen Thurber

    I’ve had diabetes for approximately 10 years now. My doctor has me taking Metformin as well as Bydureon and Tresiba. I’ve had diabetic retinopathy as well in the last two years, which I get injections for. I’ve been on the Tresiba for about 2 years now. I desperately want to get off all these medications and be free of diabetes for good. I have started the intermittent fasting for about the last month or so – I fast from about 9pm to 6pm the next day, drinking only water. My sugar levels have improved, especially on fast days. What are my chances of getting off all these meds and being free of the disease as well as having the blurriness of my eyes improve? Is there anything else I should be doing to help this happen? Thanks so much!

  • LInda GAbin

    Dr Redmond
    I would like to try the fasting . My weight has really gone up in the last 6 months and it is because my meds have been increased . I also want to try the meds you have offered . What I would like to know is how long do I have to stay on the fasting? Is this a process I would have to continue the rest of my life? I have to return to my doctor in April and I am suppose to have lost 15 pounds so I was hoping this would help me because as of now I have not lost any.since last month when I started cutting my carbs and eating less.
    How much would the daily support and sugar blocker be? I am on limited income so I would hope I could get a helpful discount.
    Thank you
    Linda Gavin


    I notice it says Magnesium oxide. Isn’t this a chesper less absorbed form of Mg?? Thanks

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