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EventsDr. Jason Fung answers questions about intermittent fasting
, medical content by Dr. Jason Fung, MD
in Dr. Jason Fung, Intermittent fasting, Q&A 
Here are a number of questions answered by Jason:
High morning blood sugar
Dr. Fung,
I have read and re-read everything on your blog and this site for nearly a year. I have T2D and have been following LCHF, and doing some IF. I currently take 1000 mg of metformin. This was recently reduced because my A1C came down to 5.2! I feel great about the progress I have made but the dawn phenomenon still has me puzzles. My numbers in the morning are always in the 130’s. I want them lower!
Should I not be concerned about this? I have read your blog about DP, but I’m not quite sure if you are saying that high numbers in the morning don’t matter or if I should expect to see them come down in time. It seems to me that recently my morning numbers have gone up- Can you clear this up for me?
Dr. Jason Fung: Your DP indicates that you have not entirely gotten rid of insulin resistance. Sometimes it just takes more time. Insulin resistance is a time dependent phenomenon. It can take years to develop and can take months-years to go away.
I wouldn’t worry particularly about it. But it does mean you have more work to do.
Read more in Diet Doctor’s guide to insulin resistance.
Is drinking broth really fasting?
Dear Dr.Fung,
Thank you very much for all your help and for the lovely website,
I was just wondering regarding the broth, how come we can have it during the fasting since I believe it contains some fat/ some proteins/ and some calories from the bone and meats which are boiled… I’m just thinking aren’t we are better off without it and stick to water tea, for a proper fast?
Thank you
Dr. Jason Fung: Yes, the broth technically breaks the fast. We use it more in extended fasts for 2 reasons. First, the small amount of protein makes very little difference to most people. Second, it reduces the risk of re-feeding syndrome. If you would like to stick to water fasting, that is fine, too.
Should I eat more often?
Dear Dr. Fung,
This is one of the best life changing regimen I have ever done and it is showing great results in my blood work as well, recently I’ve been going through a body fast were I wake up not hungry and eat only when I feel the need to (still trying to control that, wait too long I guess before eating) as well I workout twice a day.
Do I continue with this concept where I eat when I need to or time it in a way to eat every 8 hrs, it’s very confusing since I am still considered a Diabetic (hopefully not for too long).
Just to add, I was diagnosed as a diabetic in Jan 2015 with A1c of 6.5; Lantus 8 units; 1000mg Metformin and before the diet the A1c was 5.5 on Oct 2015, now after 3 months my A1c is 4 and recently taking 500 mg Metformin and no Lantus (had to reduce/remove since I went into hypo a few times). Sadly I live in Bahrain and there are no Doctors that agree to this diet and no one to support, so doing this on my own with experimentation and checking my results on a monthly basis (family has a history of BP and Diabetes with other health issues like GERD and hypertriglyceridemia which I think this is norm with T2D).
I’m guessing I am doing it right since I have done the research and saw almost all your content on the site with monthly blood works.
Dr. Jason Fung: If you are not hungry, you should not eat. That is your body telling you that it has enough energy. Where is it coming from? Your own fat stores! That’s excellent. So, continue to let your body burn the fat and don’t eat.
More
Intermittent Fasting for Beginners
More Questions and Answers
Many more questions and answers:
Read Dr. Jason Fung’s new great book The Obesity Code for many more insights:
More About Intermittent Fasting and Diabetes
I need your reassurance.
Thank you!
You may want to try our free two week challenge!
https://www.dietdoctor.com/low-carb/get-started
I understood that the fast refered to was the overnight fast when the liver produces glucose to keep blood sugar from falling too low. They found that normally the liver can switch off the production of glucose when not needed but that this switch is not working in diabetic mouses. The team from Yale is trying to come up with a drug to fix this problem.
I have a better idea:
not overloading the liver with sugar by eating a very low carb diet.....!
If you are experiencing extreme fatigue, OMAD (one meal a day) may not be a good choice for you.
This article should be helpful for you! https://www.dietdoctor.com/intermittent-fasting/omad
It sounds like you're doing as much as you can! If you're feeling sick, it's definitely not a good idea to try and force a fast, especially if you're on medication. Keeping consistently on plan will help with the weight loss also.
It seems prudent to stop fasting if you are not feeling well.
Please check in with your doctor to evaluate your symptoms. Dr Fung does not recommend longer fasts without doctor supervision for issues such as this.
Im not on any meds..3 years ago my dr told me that i shud loose weight naturally.
If you are taking medications, you need to check with your healthcare provider about whether you can continue them during a fast. We can't give individual advice about that as it can be individualized in many circumstances.
I've been listening to Dr. Fung's lectures on You Tube, and have been doing 8/16 IF for about a month now, and plan to stick with it long term.
Dr. Fung has indicated that even long fasts can be very beneficial for losing weight. In this light, I'm curious about a particular case I witnessed: A relative living in an Asian country undertook at month-long fast under the direction of a fasting guru. The only thing she ingested during that time was, as recommended in the fasting program, a special herbal tea and a teaspoon or so of fermented soy bean paste per day for salt intake. She was able to do complete the fast without much difficulty and very little hunger. She lost a lot of weight, and her skin improved, as did her allergies and sleep. However, when she went off the fast after a month, I noticed she ate a lot, including snacks. She seemed to be compensating for all those days of not eating. She eventually regained all the weight.
Any ideas about what went wrong here? Is the compensatory eating mostly psychological, or something else?
Would she have been able to keep off the weight if she'd maintained a schedule of IF long term, rather than going back to regular eating and snacking, or if she'd kept to a lower carb diet?
Thank you,
DT
Overeating will certainly cause weight gain. IF is not required for weight loss or weight maintenance. Please keep in mind that we recommend a doctor's supervision for any fast lasting longer than 36 hours. This article about longer fasts may be helpful! https://www.dietdoctor.com/longer-fasting-regimens