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Blood glucose level during intermittent fasting.

sanmad

Newbie
Messages
4
Type of diabetes
Treatment type
Diet only
I was diagnosed with Pre-diabetes about 40 days back. My fasting blood glucose level first thing in the morning (after 10 hours of fasting) varies between 110 and 125. Reading Jason Fung, I started on intermittent fasting regime where I started skipping breakfast. And also cut down on carbs.
I noticed that by the time my fasting time period entered about 15 hours (around lunch time), my blood glucose would drop to about 85. I felt happy about that.

However after doing a month of that intermittent fasting, I am realizing that my blood glucose level now stays constant during the fast from morning till lunch time. So if the blood glucose level is 115 in the morning, it will stay constant even at 115 when I continue to fast late into the afternoon, Even if started the day at 115 and I do not eat till 3 pm in the afternoon, it still stays at 115.
Does it mean that my Diabetes is worsening?
 
@sanmad
Hello and welcome to the Forum :) Here is the Basic Information we give to new members and I hope you will find it both interesting and helpful.

BASIC INFORMATION FOR NEW MEMBERS

Diabetes is the general term to describe people who have blood that is sweeter than normal. A number of different types of diabetes exist.

A diagnosis of diabetes tends to be a big shock for most of us. It’s far from the end of the world though and on this forum you'll find well over 300,000 people who are demonstrating this.

On the forum we have found that with the number of new people being diagnosed with diabetes each day, sometimes the NHS is not being able to give all the advice it would perhaps like to deliver - particularly with regards to people with type 2 diabetes.

The role of carbohydrate

Carbohydrates are a factor in diabetes because they ultimately break down into sugar (glucose) within our blood. We then need enough insulin to either convert the blood sugar into energy for our body, or to store the blood sugar as body fat.

If the amount of carbohydrate we take in is more than our body’s own (or injected) insulin can cope with, then our blood sugar will rise.

The bad news

Research indicates that raised blood sugar levels over a period of years can lead to organ damage, commonly referred to as diabetic complications.

The good news

People on the forum here have shown that there is plenty of opportunity to keep blood sugar levels from going too high. It’s a daily task but it’s within our reach and it’s well worth the effort.

Controlling your carbs

The info below is primarily aimed at people with type 2 diabetes, however, it may also be of benefit for other types of diabetes as well.

There are two approaches to controlling your carbs:

  • Reduce your carbohydrate intake
  • Choose ‘better’ carbohydrates
Reduce your carbohydrates

A large number of people on this forum have chosen to reduce the amount of carbohydrates they eat as they have found this to be an effective way of improving (lowering) their blood sugar levels.

The carbohydrates which tend to have the most pronounced effect on blood sugar levels tend to be starchy carbohydrates such as rice, pasta, bread, potatoes and similar root vegetables, flour based products (pastry, cakes, biscuits, battered food etc) and certain fruits.

Choosing better carbohydrates

The low glycaemic index diet is often favoured by healthcare professionals but some people with diabetes find that low GI does not help their blood sugar enough and may wish to cut out these foods altogether.

Read more on carbohydrates and diabetes.

Over 145,000 people have taken part in the Low Carb Program - a 10 week structured education course that is helping people lose weight and reduce medication dependency by explaining the science behind carbs, insulin and GI.

Eating what works for you

Different people respond differently to different types of food. What works for one person may not work so well for another. The best way to see which foods are working for you is to test your blood sugar with a glucose meter.

To be able to see what effect a particular type of food or meal has on your blood sugar is to do a test before the meal and then test after the meal. A test 2 hours after the meal gives a good idea of how your body has reacted to the meal.

The blood sugar ranges recommended by NICE are as follows:

Blood glucose ranges for type 2 diabetes
  • Before meals: 4 to 7 mmol/l
  • 2 hours after meals: under 8.5 mmol/l
Blood glucose ranges for type 1 diabetes (adults)
  • Before meals: 4 to 7 mmol/l
  • 2 hours after meals: under 9 mmol/l
Blood glucose ranges for type 1 diabetes (children)
  • Before meals: 4 to 8 mmol/l
  • 2 hours after meals: under 10 mmol/l
However, those that are able to, may wish to keep blood sugar levels below the NICE after meal targets.

Access to blood glucose test strips

The NICE guidelines suggest that people newly diagnosed with type 2 diabetes should be offered:

  • structured education to every person and/or their carer at and around the time of diagnosis, with annual reinforcement and review
  • self-monitoring of plasma glucose to a person newly diagnosed with type 2 diabetes only as an integral part of his or her self-management education

Therefore both structured education and self-monitoring of blood glucose should be offered to people with type 2 diabetes. Read more on getting access to blood glucose testing supplies.

You may also be interested to read questions to ask at a diabetic clinic.

Note: This post has been edited from Sue/Ken's post to include up to date information.
 
Hello @sanmad and welcome and thanks @Debandez for the tag.

@bulkbiker is much more knowledgeable in this area than me, but I use intermittent fasting a lot - skipping breakfast every day and reasonably often eating only one meal a day. When I eat more than once, I try to have an eating window of no more than 5 hours.

You’re newly diagnosed so may have some variation in readings while you adjust your way of eating and your body settles down.

Fasting not an exact science - and there are many reasons why blood glucose levels may not drop in the same way each time. I’m referencing a few short articles below.

A couple of questions for you also.

1) Have you changed what you are eating to end your fasts? I.e. has carb creep become an issue (posting a typical menu may help people to spot patterns)
2) How often are you testing during the fast? Are you sure you remain constant all that time, or could it be that you drop lower and then rise back up? I quite often find that I’ll drop to a low point and then my liver will kick in and push the reading up a bit, but in those circumstances my post prandial reading will likely be lower.
3) What happens to your post prandial readings? Have they changed since you noticed the change in your fasting readings?

https://www.dietdoctor.com/low-carb/fasting-blood-glucose-higher

https://www.dietdoctor.com/why-does-blood-sugar-increase-during-a-fast

https://www.dietdoctor.com/intermittent-fasting/questions-and-answers
 
Thank you @Debandez and thank you @Goonergal .
Hi @Goonergal , I really appreciate such a thoughtful response. Let me go through the links you provided. Regarding your questions:
1 I eat a large salad, some nuts and small amount of bread to break fasts in the lunch time. My fasting period is usually just skipping breakfast. Sometimes I delay lunch till 3 pm. Dinner is some vegetables and a little bit of whole wheat tortilla and yoghurt. Sometimes I will meat during the dinner but only once in a week.

2. Good point. I tested only once or twice during the fast. But only towards the end. So its entirely possible that I went down and came up.

3. I have not measured post prandial with any discipline. Sometimes I have measured pretty high (close to 180) after an hour or two after meal. But it comes down to 110-120 or so if I wait 4 hours or more. What cadence would you recommend? Like 2 hours after meal?
One thing I have noticed is that just before I go to sleep my blood sugar is pretty much the lowest (110) compared to any other time in the day. I sleep around 11:30 pm. I usually eat my dinner by 7:30 pm.
 
Thank you @Debandez and thank you @Goonergal .
Hi @Goonergal , I really appreciate such a thoughtful response. Let me go through the links you provided. Regarding your questions:
1 I eat a large salad, some nuts and small amount of bread to break fasts in the lunch time. My fasting period is usually just skipping breakfast. Sometimes I delay lunch till 3 pm. Dinner is some vegetables and a little bit of whole wheat tortilla and yoghurt. Sometimes I will meat during the dinner but only once in a week.

2. Good point. I tested only once or twice during the fast. But only towards the end. So its entirely possible that I went down and came up.

3. I have not measured post prandial with any discipline. Sometimes I have measured pretty high (close to 180) after an hour or two after meal. But it comes down to 110-120 or so if I wait 4 hours or more. What cadence would you recommend? Like 2 hours after meal?
One thing I have noticed is that just before I go to sleep my blood sugar is pretty much the lowest (110) compared to any other time in the day. I sleep around 11:30 pm. I usually eat my dinner by 7:30 pm.
Careful with the bread/tortilla
 
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