Would you ever put people with type 2 diabetes on insulin?

Ask Dr. Jason Fung

How can a person with type 2 diabetes lower their HbA1c? Would you ever put a person with type 2 diabetes on insulin? What is a normal insulin level? And, can you have celery, radishes and lettuce during a fast?

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

Low serum insulin + High HbA1c

Dear Dr. Fung,

Have you come across a situation in which a person on LCHF and IF has been able to bring fasting insulin levels down but HbA1c stays high? If T2D for 20 years; after 3.5 years of LCHF and IF, fasting serum insulin is 3.8, but HbA1c remains at 8-9. I would like to understand the science behind this and how to reduce HbA1c. Thank you.


We’ve seen every possible combination. Latent onset type 1 diabetes is a situation where fasting insulin may fall over time and blood glucose remains high.

Dr. Jason Fung

Would you ever put T2D on insulin?

If you had a patient who was strictly keto for a month but after removing meds such as gliclazide, due to the stress it puts on the pancreas, but was still taking maximum metformin but waking on 12-17 would you introduce insulin? How long would you give the body to rid itself of sugar naturally? I would be interested in your approach. Hypothetically of course. Thanks.


Every situation is unique, and I treat patients on an individual basis, but yes, I’ve put many people with type 2 diabetes on insulin. Other than that, I can’t answer specific cases.

Dr. Jason Fung

What is normal insulin levels?

Dr Fung,

I read your book the Diabetes Code about reversing type 2 diabetes and you talked about insulin toxicity in T2DM patients. On page 58, a diagram shows fasting insulin levels in obese people. Can you tell me in general what is the normal insulin range (pmol/L) for diabetics who are not over weight or obese, but have a diagnosis of T2DM? Thank you.


You need to check with your own lab. Each lab has different levels that they consider normal.
Dr. Jason Fung

Can I eat celery, radishes and lettuce during my fast?

Hi Dr Fung,

I was thinking that as these are extremely low in carbs, they would no affect the fat-burning that occurs during a fast? They also help with the cravings and chewing on them seems to help me.


Fasting is classically just water and no food. You can do a variation of fasting that allows celery, radishes, and lettuce, and that may certainly be successful for weight loss.

Dr. Jason Fung

Q&A videos

Top Dr. Fung videos


Intermittent fasting for beginners

A keto diet for beginners

Earlier Q&A

Intermittent fasting Q&A

More with Dr. Fung

All posts by Dr. Fung

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

The Obesity CodeThe Complete Guide to Fastingthe-diabetes-code (1)

Dr. Fung’s books The Obesity Code, The Complete Guide to Fasting and The Diabetes Code are available on Amazon.1

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