Is intermittent fasting a good idea when suffering from stress?

Ask Dr. Jason Fung

Is it OK to consume your daily protein at one meal? Is intermittent fasting good for people with adrenal dysfunction due to stress or other factors? And what about The Dawn Phenomenon – is it good or bad?

It’s time for this week’s Q&A about intermittent fasting and low carb with Dr. Jason Fung:

Is it OK to consume your daily protein at one meal?

I intermittent fast for 24 hours, is it OK to have my daily protein requirement of 58 grams at one meal or would it be better to split it up over 2 hours as I’m insulin resistant?

Thank you for all your help,

I suspect it makes little difference.

Dr. Jason Fung

Would you still recommend intermittent fasting if I have adrenal dysfunction?

I have adrenal dysfunction…? I’m stuck in a stress response… High cortisol, high insulin, overweight/obese, fatigued, hypothyroid/Hashimoto’s…. Would you still recommend intermittent fasting?


Fasting is not useful for lowering cortisol – only insulin. Fasting is a stress upon the body, just like exercise. Both are good in correct doses and with appropriate use. So if excess stress is your problem, then no, fasting is not the answer.

Decreasing the stress (cortisol) response does not depend upon the diet. Yes, excess stress may make you gain weight, but you need to deal with the underlying cortisol. Meditation, yoga, tai chi, exercise, proper sleep, acupuncture, community (going out with friends), spirituality, religion are all methods of altering the stress response.

Dr. Jason Fung

The Dawn Phenomenon – is it good or bad?

Hi Dr. Fung. Hope you’re well.

I am now into week 6 of intermittent fasting (16-18 hour fasts per day). Things are good. I know you (rightly) say that high blood sugar levels are just a symptom. However, my blood sugar after meals have improved greatly with my fasting regimen. 2-hour post meal readings are usually around 5.5 mmol/L (99 mg/dl) or at their highest 6.6 mmol/L (120 mg/dl). That’s even with slightly high-carb meals and this is without any diabetic medication whatsoever.

The problem is that my fasting blood glucose levels have risen. I used to have FBG of 5.5 mmol/L (99 mg/dl) and it’s now somewhere near the 7 mmol/L (126 mg/dl) mark. I’ve read most of your blogs and I have read about the Dawn Phenomenon etc. My question is are these raised morning fasting glucose levels potential signs of progress? Do you see similar trends in other patients? I know it’s hard to guess, but could this take months of intermittent fasting to resolve?

Many thanks,

Yes, it can take months for the Dawn Phenomenon to resolve. It’s neither really good or bad. It just means that you have excess sugar. I’ve written more extensively here.

Dr. Jason Fung



Intermittent Fasting for Beginners

How to Reverse Type 2 Diabetes – The Quick Start Guide

Earlier Q&A sessions with Dr. Fung:

Intermittent Fasting Q&A

Q&A videos

Top Dr. Fung videos

More with Dr. Fung

Dr. Fung has his own blog at He is also active on Twitter.

His book The Obesity Code is available on Amazon.

The Obesity Code

His new book, The Complete Guide to Fasting is also available on Amazon.


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