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Fasting Glucose Higher Than You Expect On A Low Carb Or Ketogenic Diet?

Thank you for posting this.

I have been getting higher fasting BGs than I would have expected since changing from 50-80g carbs to around 20 g carbs daily. I naively thought that the fact that I had been producing ketones since going to the lower amount meant that my BGs would plummet quickly. It's nice to know the reasons why this hasn't happened.
 
A very interesting read.

I have been pursuing a LCHF diet for a couple of months or more and have got to the stage where my BG readings throughout the day have been going in "reverse" almost. I wake up to a 6 to 6.5, rise a bit further as the morning progresses and then start to fall after lunch until I get to about 5.3 just before bed. After meals there is no spike - in fact typically I register a drop 2 hours after eating.

I'd like to think that this provides the explanation for me....but as with all things associated with T2 there are many entwined factors so I am not going to 100% accept this is the answer for me. My latest HbA1c results are due any day so its will be interesting to see how that matches up with my own monitoring.
 
I find this to be true for me also but I am not spiking through out the day.
Higher in the morning and great numbers the rest of the day.
 
It matches my experience perfectly. The lower I go with carbs, the higher my fasting BG becomes.
 
Makes me feel better about my 'orrible FBGs.
 
Yes me too I am not so worried about my FBGs now ...lost another pound . I like ketosis.
 
Yes my fasting readings have often been hgher than might be expected from my other levels for most of the time (over four years) that I've been eating a low carb/ketogenic diet. However since they don't appear to be a problem as they seem to have little impact on my overall results, and I've assumed my liver knows what it's doing, they've never been a real concern.

Robbity
 
Ask your Dr or diabetes practitioner about splitting your Lantus dose into morning and evening. Lantus does not last a full 24 hours so you might be a bit light in the afternoons allowing your BG to rise and perhaps peak after an evening meal as your evening Lantus will take several hours to be effective (note - do not do this without medical advice). I did this about 2 years ago and my HbA1c improved markedly.
 
I have been mulling over this for a day or so and after another day of 6's in the morning lowering to low 5's in the evening after dinner, I wonder what impact a high carb meal would have for someone in a "adaptive glucose sparing" state*. Can the pancreas and body react to manage glucose or would it lead to a big BG spike?

The author is using mindfulness (I'm classing yoga as mindfulness) to try and manage those higher FBG levels and this interests me. I am certain stress/lack of sleep/jetlag plays a big part in my higher BG levels. I need to be far more disciplined in taking time out to try some relaxation techniques. (That sounds like an oxymoron but you know what I mean!! )

*I'm not volunteering to find out.
 
That's fine if you're a T1 or T2 on insulin, but many of us T2s have to control our glucose by our diet (or diet and oral meds) alone.

This was one of the first patterns I discovered after I got my meter, and in fact it made me decide to split my metformin dose to morning and evening, instead of just evening. (Though now I know that this shouldn't - and actually didn't - make much difference though!)

Robbity

ETA And yes, eating more carbs can often spike my levels too depending on quantity, but so too can stress, illness, pain - and these generallly more so than the extra carbs can!
 
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Hi @TonyHancock my levels follow a similar pattern to your, waking mid to high 5’s to low 6’s then continue to rise slightly during the morning, regardless of whether I eat breakfast or not.
Lunchtime and onwards the numbers lower and yes, occasionally I get a lower post meal reading. As you say lots of factors to consider, very rarely are 2 days alike.
Good luck for your next HbA1c I hope you are rewarded with numbers that you are happy with.
 
My bgs are in the 4s again for past few mornings. I was reading a piece by Ted Naiman... that eating cheese in evening before bed can also cause a morning “rise”

I was doing that and stopped. Things seem to be back to normal for me.
 
I decided to record my BG more frequently yesterday and took the following readings - along with food/drink/exercise

Aug 5th 21:43 - 5.3 (Bedtime)
Aug 6th 08:40 - 7.0 (Fasting)
Aug 6th 10:25 - 7.2 (Just tea with whole milk at this stage)
Aug 6th 11:27 - 7.4
Aug 6th 12:28 - 7.5 (Coffee with double cream)
Aug 6th 13:30 - 7.0
Aug 6th 14:37 - 6.8
Aug 6th 15:59 - 6.4 (Coffee with double cream)
Aug 6th 17:36 - 5.4 (40 minute walk)
Aug 6th 20:29 - 5.8 (2 hrs after keto scotch egg, spinach, celery, cherry tomato, radish olive oil and red wine vinegar)
Aug 6th 21:24 - 5.8 (Bedtime)

I must admit I have been carrying out some googling on this subject because it may well be an explanation for my readings.

I'm hoping the 7's might drop to 6's or high 5's as my body adapts.

This morning's fasting reading is another 7.0.
 
I ate some cheese again last night. This morning BG 5.7. I think the cheese is doin me in lol. 20 min hard cycle and BG down to 4.9.
 
Got my Codefree meter Wednesday so just been doing fairly random testing. One thing I have noticed very quickly is that for the first test when I get up has been 9.1 & 7.8 but tests at about 4pm were 6.2 & 5.8 (both about 2 hours after eating). Other posts seem to suggest lower readings in the mornings.

Not worried just curious. Trying to avoid going on meds and have lowered carbs and upped the exercise in last few weeks.
 
Congratulations on your efforts. To explain your higher fasting bgs, you might want to look at what you are eating for dinner, and when. Is your last meal of the day at 4pm? Once we are horizontal our digestions tend to slow down, so that if you are eating a big meal too near to bedtime that might be one explanation. Some of us including myself find that our bodies handle carbs worse at dinner and breakfast, which leaves lunch as the biggest meal of the day - not very convenient! Alternatively, if your last meal of the day is at 4pm, it is possible that your body doesn't like your fasting for so long, and you might get a better fasting reading in the morning by eating a little something before bed. It's a matter of experimenting. You could search for the "dawn phenomenon" where many of us have discussed this.

I suggest increasing your testing for a while. You will have a better idea what is going on if you test immediately before meals, and after meals at 1 hour and 2 hours. Theoretically, a normal person's bg rises in the first hour and has gone down again by hour 2. However, delayed stomach emptying (a common complication of diabetes from which I suffer) and a large and/or rich meal can all cause a later rise and, therefore, a later fall. Or bg can go up and then not come down for hours. So it is a good idea to test at 3 hours and maybe even 4. The aim is to see how much your bg rises and how soon it falls back to its pre-meal level. Once your bg has fallen back to its pre-meal level, you don't need to test again until just before your next meal.

You say you want to avoid meds, and many people feel as you do. However personally I have chosen to take the maximum dose of Metformin as it is considered a trusted and benign drug. IMO keeping my bg as low as possible is absolutely vital, and my number one priority. I am eating very low carb but my bg levels are still not what I want, so I am glad to take Metformin as well.
 
Thanks Alexandra thats very useful. Very rarely do I eat a meal after 7:30pm and usualy in bed for 10:30 - 11:00. Had a 9 before breakfast this morning and down to 4.6 before lunch at 1pm. Breakfast was 1 slice of seeded wholemeal toast with marmite and a glass of very diluted fresh orange juice. Had 20 mins quick paced walk about 8:30. Lunch was tin of tuna in spring water with salad not tested since ( tut tut) dinner was fried (veggie oil) pork strips and veg, no potatoes
Just tested now and bg is 7.7, w and a half hours after eating.

I am not totally against taking Metformin but to my mind it is good to know how meal times etc. affect bg before jumping in.
It was my doc who prescribed Metformin by DN said she wouldnt have done (Hba1c at last test was 62 or 7.8 in old money).

Really appreciate your advice and will increase my testing.

Thank you. X
 
So maybe dawn phenomenon. Did you test after breakfast?

I am not clear what diet strategy you are following. It sounds rather like highish carb low fat? Did you know that orange juice is often used by T1s to boost their bg as quickly as possible when they suffer hypos? I take it the morning readings you are quoting are taken fasting immediately after getting up and going to the loo? Given these puzzling highs I suggest testing just before bed.

I'm glad you have not decided definitely against Metformin. However there is some research suggesting that it does most good if started asap after diagnosis. This is from Jenny Ruhl:

"Metformin Started Early Far More Effective than Metformin Started Later
A study published of 1,799 Kaiser patients who were able to lower their A1c below 7.5% using Metformin found that when patients were started on Metformin immediately after diagnosis, they were able to stay at an A1c lower than 7% for longer than did patients whose doctors waited a year before starting them on the drug.
Secondary Failure of Metformin Monotherapy in Clinical Practice Jonathan B. Brown. Diabetes Care Diabetes Care March 2010 vol. 33 no. 3 501-506 doi: 10.2337/dc09-1749
A more detailed discussion of this study can be found here:
Diabetes in Control: Early Treatment Doubles Chance of Success for People with Diabetes
This is important. Many people with diabetes resist taking a drug thinking that it is better to attempt to lower blood sugar with diet or exercise alone. Because the action Metformin is different from the effect of cutting carbs or exercising, this may be a mistake. It may be better to start metformin along with other approaches as soon as you receive a diagnosis of abnormal blood sugar (including a diagnosis of pre-diabetes) rather than waiting."

You can read the whole article on Metformin here: https://www.bloodsugar101.com/metformin
 
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