Could chronic stress damage the metabolism over time?

Ask Dr. Jason Fung

Could stress over time damage your metabolism, resulting in weight gain or even type 2 diabetes? Can dairy protein be a problem? And could fasting reduce the chances of getting pregnant?

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

Does dairy protein intake makes it difficult to reverse diabetes?

I am a vegetarian and have some food intolerances and have to rely mainly on eggs and dairy proteins (cheese/paneer and yogurt) for my protein requirements.

Is there any evidence to suggest that dairy protein might make it difficult to reverse type 2 diabetes as it is highly insulinogenic?

I would highly appreciate your comments.


There is evidence that high intake of dairy fat (full fat cheese, yogurt, milk etc) is correlated to a lower risk of type 2 diabetes. Most natural dairy foods are not high protein. So I think natural full fat dairy products are good. However, I don’t recommend highly processed dairy foods eg. whey protein shakes. The whey protein is highly insulinogenic and removing it from the dairy fat may make things worse.

Dr. Jason Fung

Stress… It’s bad!!

Hope you’re well Doc. Great work!

I try to learn from many diabetes resources including most of your work. I find that most of the information out there is regarding nutrition, weight loss, fasting, diet etc. What about stress?

Now, no soul may pass through this wordly life without trial or tribulation. This is just the way things are. But in our lovely modern world, with its fast pace of living and constant distractions, I feel people are becoming more stressed.

Can stress (especially long term chronic stress) play a significant role in the development of type 2 diabetes? Going further… Can stress be the cause or at least one of the major root causes of this disease? We know long term stress can increase cortisol levels and this may in turn drive up blood sugar levels. Also, stress as we know can wreak havoc on one’s body. I have a friend who has skin that flares up when he’s under pressure. I have a niece who has very bad stomach complaints when she worries. In the past, I’ve lost weight through stress. So stress, commonly perceived to impact the psychological and the emotional can also be seen to be devastating to the physical. Could stress over time damage the pancreas/liver/metabolism? Your opinion on this would be greatly appreciated.


Yes, chronic stress can cause many problems including weight gain and type 2 diabetes. Cortisol is the hormone released during stress. This was an adaptation to acute stress (like getting chased by a lion) where you would either be dead or safe. Either way, cortisol goes down. In modern times, stress is chronic (school, marriage, work) where it becomes detrimental to our health. You can see the effects when people take chronic doses of synthetic cortisol (prednisone). In addition to weight gain, people get type 2 diabetes, cataracts, high blood pressure, skin problems, acne, ulcers, striae and numerous other problems. So yes, chronic stress is bad for many many reasons.

Dr. Jason Fung

Hormones, fertility and fasting

Can short term fasting negatively affect a woman’s hormones and fertility? I already have unexplained amenorrhea for the past 10 years. I am 36. Not over or underweight. One doctor thought I had PCOS and another does not think I have PCOS. I had two children using clomid. I enjoy fasting for short periods of time (dinner to 10 am or noon next day for example), but not every day of the week. Could this be helpful or detrimental to my hormones (since they are obviously already somewhat out of whack)?


Fasting causes many hormonal changes – but mostly related to hormones such as insulin, norepinephrine, cortisol, and growth hormone. It has minimal effect on sex hormones such as estrogen and progesterone. Not zero, but little effect. So, generally, fasting is not harmful unless you are severely underweight (which you should not be fasting anyways).

Dr. Jason Fung



Intermittent Fasting for Beginners

How to Reverse Type 2 Diabetes – The Quick Start Guide

Earlier Q&A sessions with Dr. Fung:

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.


Leave a reply

Reply to comment #0 by

Older posts