Why your fasting blood sugar might still be high on low carb

September 9 2017 by in Blood sugar, Diabetes, Low carb & high fat

It’s not too uncommon to have slightly high fasting blood sugar on low carb and keto diets. Is this a problem?

It depends on your insulin levels, as outlined by Dr. Ted Naiman below. If you’re insulin sensitive, and have slightly higher fasting blood glucose, it’s likely just fine.

The dawn phenomenon – why are blood sugars high in the morning?

Low carb for beginners

How to reverse type 2 diabetes

Insulin

Insulin toxicity — Dr. Jason Fung's diabetes course
09:03
Dr. Fung looks at the evidence on what high levels of insulin can do to one’s health and what can be done to lower insulin naturally.
Part 7 of Dr. Jason Fung's diabetes course
05:01
Dr. Fung gives us a comprehensive review of what causes fatty liver disease, how it affects insulin resistance and, what we can do to reduce fatty liver.
The pathways of insulin resistance
30:41
Are we chasing the wrong guy when it comes to heart disease? And if so, what is the real culprit in the disease?
Is obesity caused by too much insulin?
25:27
Is obesity mainly caused by the fat storing hormone insulin? Dr. Ted Naiman answers this question.
Diet Doctor Podcast #35 with Ben Bikman, PhD
00:00
Why is insulin so important for us to control and why does a ketogenic diet help so many people? Professor Ben Bikman has studied these questions in his lab for years and he is one of the foremost authorities on the subject.
Weight control – calories or insulin
36:26
Is weight loss controlled by calories in and calories out? Or is our body weight carefully regulated by hormones?
Insulin resistance and sexual health — Dr. Priyanka Wali
23:24
Is there a connection between insulin resistance and sexual health? In this presentation, Dr. Priyanka Wali presents several studies that have been made on the subject.
The key to obesity
44:22
How insulin toxicity causes obesity and type 2 diabetes – and how to reverse it. Dr Jason Fung at the LCHF Convention 2015.
What causes insulin resistance?
29:01
No less than 70% of people die from chronic disease, connected to insulin resistance. Dr. Naiman explains what causes it.
Why we get fat
47:30
Why do we get fat – and what can we do about it? Gary Taubes at Low Carb USA 2016.
Hyperinsulinemia - what insulin does in your body
45:29
Controlling the insulin in your body can help you control both your weight and important aspects of your health. Dr. Naiman explains how.
Why you shouldn't fear protein on keto
20:15
Do you really need to worry about protein on a ketogenic diet? Dr. Ben Bikman shares a new way of thinking about this.
The carbohydrate-insulin model of obesity — Dr. David Ludwig
37:54
In this presentation from the Low Carb Denver 2019 conference, Dr. David Ludwig walks us through the latest discoveries on how weight gain and weight loss actually work in practice.
Diet Doctor Podcast #28 – Amy Berger
54:29
Amy Berger has a no nonsense, practical approach that helps people see how they can get the benefits from keto without all the struggles.
Diet Doctor Podcast #29 – Dr. Spencer Nadolsky
47:49
Dr. Spencer Nadolsky is a bit of an anomaly as he openly wants to explore low carb nutrition, low fat nutrition, multiple forms of exercise, and use it all to help his individual patients.
How to measure your insulin response
29:27
How do you measure your insulin-response pattern?

Advanced low-carb topics

Common mistakes on low carb
15:47
Do you have a hard time losing weight on low carb or keto? Then perhaps you're making one of the common mistakes.
Why more protein is better
15:17
Dr. Ted Naiman is one of the individuals who believes more protein is better and recommends a higher intake. He explains why in this interview.
A new life with a keto diet
13:38
If your muscles can't use stored glycogen, is it then a good idea to eat a high-carb diet to compensate for this? Or can a keto diet help treat these rare glycogen storage diseases?
How to think about how to eat — Gary Taubes
30:34
In this presentation from the Low Carb Denver conference, the amazing Gary Taubes talks about the conflicting dietary advice we are given and what to make of it all.
Exploiting cancer metabolism with ketosis
44:42
Can a ketogenic diet be used in cancer treatment? Dr. Angela Poff at the Low Carb USA 2016.
Framingham and the Muddy Waters – part 1
21:00
What’s the real cause of heart disease? How do we most effectively estimate someone’s risk?
Grass based health and the ruminant revolution
47:53
Is red meat really that bad for the environment? Or could it play a positive role? Dr. Peter Ballerstedt at the Low Carb USA 2016.
Diet Doctor podcast #15 with Prof. Andrew Mente
39:57
As an epidemiology study, how much faith can we place in the results, and how do these results fit into to our current knowledge base? Professor Mente helps us make sense of these questions and more.
Will a low carb diet shorten your life?
30:57
In this highly insightful presentation from Low Carb Denver 2019, Robb Wolf takes us through studies which can help us better understand weight loss, food addiction and health on a low-carb diet.
Does fiber make you fat?
31:09
What role does gut flora play for your health? And what about the microbiome and obesity?
Weight control – calories or insulin
36:26
Is weight loss controlled by calories in and calories out? Or is our body weight carefully regulated by hormones?
Weight loss and type 2 diabetes reversal on low carb – is it sustainable?
31:51
In this presentation, Dr. Andreas Eenfeldt goes through the scientific and anecdotal evidence, and also what clinical experience tends to show, regarding the long-term effects of low carb.
The truth about low-carb performance
20:43
Is it possible to exercise on a strict low-carb diet? Professor Jeff Volek is an expert on the topic.
45:29
Although it is new in popularity, people have been practicing a carnivore diet for decades, and possibly centuries. Does that mean it is safe and without concern?
Nutrition nuggets to combat conventional dietary advice
45:06
What are the seven common beliefs that are just myths, and that hold us back from understanding how to eat truly healthy foods?
Diet Doctor podcast #7 – Megan Ramos
54:01
In the seventh episode of Diet Doctor Podcast, Megan Ramos, co-director at IDM program, talks about intermittent fasting, diabetes and her work together with Dr. Jason Fung at the IDM clinic.
How to break a weight plateau
13:52
Are you experiencing a weight-loss plateau? Dr. Westman explains how to restart your weight loss.
Women's questions introduction
01:36
In this video series, you can find expert views on some of your top questions about low-carb and women's health.

Diabetes

The essential problem with type 2 diabetes
05:09
Dr. Fung's diabetes course part 2: What exactly is the essential problem of type 2 diabetes?
Living low carb with Chris Hannaway
08:19
What does living low carb look like? Chris Hannaway shares his success story, takes us for a spin in the gym and orders food at the local pub.
How to reverse type 2 diabetes
10:21
Dr. Fung's diabetes course part 1: How do you reverse your type 2 diabetes?
Part 8 of Dr. Jason Fung's diabetes course
05:21
Dr. Fung gives us an in-depth explanation of how beta cell failure happens, what the root cause is, and what you can do to treat it.
My success story with Kenneth Russell
02:52
When Kenneth turned 50, he realized that he wouldn't make it to 60 the way he was going.
Why low-fat diets don't work — Dr. Jason Fung's diabetes course
09:16
Does a low-fat diet help with reversing type 2 diabetes? Or, could a low-carb, high-fat diet work better? Dr. Jason Fung looks at the evidence and gives us all the details.
My low-carb story with Marc Gossange
03:01
After living somewhat of a high-carb life and then living in France for a few years enjoying croissants and freshly baked baguettes, Marc was diagnosed with type 2 diabetes.
Insulin toxicity — Dr. Jason Fung's diabetes course
09:03
Dr. Fung looks at the evidence on what high levels of insulin can do to one’s health and what can be done to lower insulin naturally.
Carb-Loaded
1:14:40
This may be the best (and funniest) low-carb movie ever. At least it's a strong contender.
Part 7 of Dr. Jason Fung's diabetes course
05:01
Dr. Fung gives us a comprehensive review of what causes fatty liver disease, how it affects insulin resistance and, what we can do to reduce fatty liver.
How to avoid complications of type 1 diabetes
37:28
Why are the recommendations to people with diabetes to eat a high-carb diet a bad idea? And what is the alternative?
Living low carb with Yvonne Lane
05:51
Yvonne used to see all those pictures of people who'd lost so much weight, but sometimes didn't really believe they were real.
Can low carb make it fun to be a doctor?
36:47
Dr. Unwin about getting his patients off medications and making a true difference in their lives using low carb.
A low-carb story with Dr. Sanjeev Balakrishnan
01:59
How can you as a doctor treat patients with type 2 diabetes? Dr. Sanjeev Balakrishnan learned the answer to this question seven years ago. Check out this video for all the details!
Diet & diabetes – how to normalize your blood sugar
16:26
Dr. Eenfeldt's get-started course part 3: How to improve type 2 diabetes dramatically using a simple lifestyle change.
The perfect treatment for diabetes and weight loss
45:20
Do doctors treat type 2 diabetes completely wrong today – in a way that actually makes the disease worse?
A disease of insulin resistance
09:30
Part 3 of Dr. Fung's diabetes course: The core of the disease, insulin resistance, and the molecule that causes it.
How to help patients reverse type 2 diabetes
27:43
How exactly do you as a doctor help patients reverse their type 2 diabetes?

Dr. Naiman

Why more protein is better
15:17
Dr. Ted Naiman is one of the individuals who believes more protein is better and recommends a higher intake. He explains why in this interview.
Is obesity caused by too much insulin?
25:27
Is obesity mainly caused by the fat storing hormone insulin? Dr. Ted Naiman answers this question.
Bodyweight training for beginners with Dr. Ted Naiman
11:35
In this video, Dr. Ted Naiman shares his best tips and tricks on exercising.
What causes insulin resistance?
29:01
No less than 70% of people die from chronic disease, connected to insulin resistance. Dr. Naiman explains what causes it.
Hyperinsulinemia - what insulin does in your body
45:29
Controlling the insulin in your body can help you control both your weight and important aspects of your health. Dr. Naiman explains how.
Becoming a low-carb doctor
19:30
How do you find a low-carb doctor? And how do we make it more simple for doctors to understand low carb?
Too much protein is better than too little
40:13
Is increasing protein intake on low carb a good or bad idea idea in terms of weight and health – and why? Dr. Naiman explains.

Earlier with Dr. Naiman

All earlier posts about Dr. Naiman

26 comments

1
rpf
September 9 2017
Interesting but hard to know for oneself since there's no easy way to get your daily fasting insulin that I know of, is there?
2
Tanya
September 9 2017
I just got a glucose monitor and was a bit worried when I saw my fasting blood sugar-6.9 mmol, almost diabetic. So no need for concern? Will it normalise?
3
Cathis
September 9 2017
How can i messure the insulinlevel my self?

Reply: #5
4
Eddie
September 10 2017
Who created this infograph?

Are the conclusions (high FBG "not a problem" if insulin profile appropriate) supported by studies?

What is best course of action for a LCing (keto at time), exercising, daily IFing, man who is concerned about "pre-diabetic" FBG and A1c?
5
Reply to comment #3 by Cathis
Peter Biörck Team Diet Doctor
September 10 2017
Hi Cathis!

There are no easy way (like for sugar and ketones) yet to do home testing for insulin levels.

How can i messure the insulinlevel my self?
6
Jennifer bowerman
September 10 2017
Am I wrong here? Most doctors don't measure insulin levels. They determine diabetes status based on blood glucose levels and then prescribe insulin or its equivalent to balance off and bring the glucose down. So high insulin is treated with high insulin. Isn't this a message Dr. Fung makes many times in his lectures?
7
It
September 10 2017
Low carb is why i became hpothyroid. Good luck.
8
Peter
June 26 2018
I've been reading a lot about this. It could just be an insulin resistant liver that takes time to get rid of it's insulin resistance.

Insulin resistance can exist at different levels in different organs.

When the liver is insulin resistant, it thinks insulin levels are lower than they actually are. This can increase glucose production in the liver. Over time because of the insulin resistance, the glucose production set point changes, going higher.

You won't notice this unless you're fasting.

Then you go on the keto diet, causing your insulin levels to be lower than what it used to be and adding intermittent fasting causing longer periods of low insulin. Now your liver thinks it has to produce more glucose. It's glucose production set point is too high.

I think the only way to change insulin resistance in the liver is through eating a lot of vegetables and exercize.

It takes 3 to 6 or more months to rid your liver from insulin resistance, depending on how bad it is. The rest of your body can have mild insulin resistance while your liver has high resistance. And without lots of vegetables it may not go away at all. (I know that a lot of people on keto don't do the healthy amounts of vegetables required, and just stuff them selves with meat, fat, eggs and dairy products.)

Just my take on it. I had glucose levels of over 105 every day after 15 hours of fasting. They would be around 85, 4 hours after eating. Now, after 9 months on keto, and below 20% protein, my fasting glucose is below 95.

High protein intake can accelerate gluconeogenesis I think. Keeping protein below 20% will also help reduce high fasting glucose levels.

Reply: #18
9
Cindi Long
July 24 2018
I'm badly type 2 diabetic, have been on an insulin pump needing 500 units per day when eating SAD, more like 200 units per day when eating better. I've done IF and LCHF a couple times when I was younger and I reversed it. I'm older now, and I tried plant based no oil last year in which I ate ONLY plants, and now trying to IF and eat LCHF is taking forever to work. My concern is that I've had only 20 g carbs daily for the last week and a half, eating only within 6 hours each day, and my blood sugar is still 250 to 300. I feel like that's too high and that I need to cautiously use insulin. Does anybody know of anybody else whose sugar stayed that high for this long? In the past I only needed 3 days to get normal blood sugar with no meds at all.

Reply: #10
10
Reply to comment #9 by Cindi Long
Michelle
August 1 2018
Cindi I’m experiencing this as well. I am eating 20g of carbs per day, taking metformin, basaglar, and Saxenda (for almost 2 weeks now) and my sugar was still 391 this morning and I hadn’t eaten for 8 hours.
11
Barbara
September 28 2018
I’m experiencing the same issue. I’ve been intaking >35 grams of carbs for the last 5 days and my fasting blood sugar is 168. I’ve been feeling to get out and walk or some type of exercise to burn off the excess sugars.
12
Barbara
September 28 2018
Oops. I used the wrong sign. I meant (less than) <35 gram of carbs per day.
13
Ronit
October 26 2018
U need to tighten your diet. I started with 43 units of insulin and 3 oral medications, diabetic for 25 years. I first went to LCHF, and slowly added IF, now I am LCHF and OMAD. It's been 6 months, and I watched my fasting sugars go from 350 to 119. I am now off the insulin, but still on the oral meds. It is taking a long time, but it's working. I also lost 25 pounds in the process. I expect to get off ALL my meds be next year
I also walk for one hour most days. Be patient, this is a Metabolic Syndrome we are repairing, this WORKS. Be patient dear, and keep at it.
Ronit

Reply: #16
14
Donna
February 26 2019
Hi I am Type 2 diabetic and am experiencing really high fasting blood sugars in the A.M. today it was high at 176.40 . I fast 23/1 and very little to no carbs. My sugars do go down and by 3pm can go as low as 88.20 . 2Hr PP after dinner - my bloods are 91.80 but just feel dismayed with the early morning high fasting levels.

Reply: #15
15
Reply to comment #14 by Donna
Kristin Parker Team Diet Doctor
February 26 2019

Hi I am Type 2 diabetic and am experiencing really high fasting blood sugars in the A.M. today it was high at 176.40 . I fast 23/1 and very little to no carbs. My sugars do go down and by 3pm can go as low as 88.20 . 2Hr PP after dinner - my bloods are 91.80 but just feel dismayed with the early morning high fasting levels.

You can read more about the Dawn Phenomenon here - https://www.dietdoctor.com/the-dawn-phenomenon

Some people find that a small amount of protein like cheese or nuts before bed will help bring that number down. If you are on diabetes medication, make sure and work with your doctor on dosage adjustments as needed.
16
Reply to comment #13 by Ronit
Kathleen
March 10 2019
We sure would like your type of results! We just had pulled pork that I made myself with no sugar or glucose and avocado with lettuce. My husband was 200 glucose afterwards. He’s trying to not use insulin. It’s maddening.
Kathleen
17
Troy
March 31 2019
Cindy Long - when the pancreas is insulin resistant it produces glucagon even in presence of food and during fasting. Liposomal GABA can be used to help improve sensitivity of pancreas. Take it when fasting - may require high doses so start small and titrate up accordingly!
18
Reply to comment #8 by Peter
Amy
June 12 2019
Hi Peter, do you have a source on the liver information presented here? Many Thanks

I've been reading a lot about this. It could just be an insulin resistant liver that takes time to get rid of it's insulin resistance.
Insulin resistance can exist at different levels in different organs.
When the liver is insulin resistant, it thinks insulin levels are lower than they actually are. This can increase glucose production in the liver. Over time because of the insulin resistance, the glucose production set point changes, going higher.
You won't notice this unless you're fasting.
Then you go on the keto diet, causing your insulin levels to be lower than what it used to be and adding intermittent fasting causing longer periods of low insulin. Now your liver thinks it has to produce more glucose. It's glucose production set point is too high.
I think the only way to change insulin resistance in the liver is through eating a lot of vegetables and exercize.
It takes 3 to 6 or more months to rid your liver from insulin resistance, depending on how bad it is. The rest of your body can have mild insulin resistance while your liver has high resistance. And without lots of vegetables it may not go away at all. (I know that a lot of people on keto don't do the healthy amounts of vegetables required, and just stuff them selves with meat, fat, eggs and dairy products.)
Just my take on it. I had glucose levels of over 105 every day after 15 hours of fasting. They would be around 85, 4 hours after eating. Now, after 9 months on keto, and below 20% protein, my fasting glucose is below 95.
High protein intake can accelerate gluconeogenesis I think. Keeping protein below 20% will also help reduce high fasting glucose levels.
19
Amie
September 13 2019
Hi just wanted to tell anyone who is reading to not give up and I pray you all get better! God bless you all!
20
Barbara
October 31 2019
Thank all of you for this great info. It really helps to know I am not alone. Strict keto 8 weeks and fasting sugars are over 200. Much worse than with normal healthy foods and meds.
I know it will get better, but none of the medical professionals or health coaches have offered any explanation.
God bless all of you!
21
Andre
April 1
I’ve been keto for almost 4 months and my fasting blood sugars range from 105-125 and my blood sugar throughout the day is 105-135. My A1C was 6.1 at the 3 month mark. I don’t know why my blood sugars can’t get below 100.

Reply: #22
22
Reply to comment #21 by Andre
Kristin Parker Team Diet Doctor
April 2

I’ve been keto for almost 4 months and my fasting blood sugars range from 105-125 and my blood sugar throughout the day is 105-135. My A1C was 6.1 at the 3 month mark. I don’t know why my blood sugars can’t get below 100.

You may want to monitor your blood sugar before and after meals to see if what you're eating is inadvertently keeping your numbers higher than you would like. You may also find this helpful.
https://www.dietdoctor.com/blood-sugar
23
Peggy
April 14
I've been LCHF for 7 years (dx with prediabetes at that time) and monitoring ketones for last 1 1/2 years. In the past week my fasting blood sugar, normally in the low 100's suddenly jumped to 140's even as ketone levels hold between 0.5 and 1.5. I eat around noon and early evening, usually protein and a vegetable or Greek yogurt with few berries. This week blood glucose tends to start dropping early afternoon to around 115 but then creeps back up through the evening. My last A1c was 5.1, from two months ago. I feel well otherwise and no other health issues but I am baffled by this new development. I have a very low tolerance for abnormal glucose levels! Part of me says cool it and just watch for now. The other part wants to fix it NOW. Any ideas as to what might be going on?

Reply: #24
24
Reply to comment #23 by Peggy
Kristin Parker Team Diet Doctor
April 14

I've been LCHF for 7 years (dx with prediabetes at that time) and monitoring ketones for last 1 1/2 years. In the past week my fasting blood sugar, normally in the low 100's suddenly jumped to 140's even as ketone levels hold between 0.5 and 1.5. I eat around noon and early evening, usually protein and a vegetable or Greek yogurt with few berries. This week blood glucose tends to start dropping early afternoon to around 115 but then creeps back up through the evening. My last A1c was 5.1, from two months ago. I feel well otherwise and no other health issues but I am baffled by this new development. I have a very low tolerance for abnormal glucose levels! Part of me says cool it and just watch for now. The other part wants to fix it NOW. Any ideas as to what might be going on?

As this is a new development, it may be worth checking in with your physician.
25
Peggy
April 15
Thank you for your response. I think I've resolved it! It appears to be a bad lot of strips. I had already replaced my monitor thinking that was the problem. My husband suggested switching to a different lot of strips and voila! Numbers returned to expected levels and finger sticks taken at the same time with the "bad" strips are consistently 20 - 40 points higher. I'll continue to monitor but I feel pretty confident that is the issue. Note to self: look for simple solutions first!
26
Peggy Nestor
April 17
My conversation with the strip manufacturer was quite enlightening so I wanted to share. I had purchased my meter and strips from Amazon. The customer rep says they have been having issues with strips purchased from Amazon giving faulty readings. Even the "new" meter I purchased a few days ago is actually an expired product that was manufactured in 2011! The company is making it right and sending me a replacement meter, strips, and control solution. She is also sending me a list of reliable distributors. I have to admit I have skipped the control solution for the last few years and presumably that would have picked up my problem strips right away. So lesson learned!