BG readings a bit high

I'm new here, recommended to this group specifically. My original doctor was Lowell Gerber, a Maine cardiologist who recommended ketosis to me.

I'm following a modified Atkins diet, about 20 mg net carbs per day. Just started for the second time about a week ago (several years ago I was in ketosis for about 3 years, and didn't need any medicines to have good blood test results). I've been taking metformin 500 mg twice a day for several years. I plan to cut down a bit, but can't get any blood tests until December because I'm on Medicare and had tests recently.

My question is this: could the metformin be keeping my morning/fasting BG readings high, or is this just an effect due to my diet? For the past week, my BG has been about 122. Yesterday and today it dropped to 118.

Knowledgeable answers only, please and thanks.


I don't think it is metformin that is raising your morning blood sugars, it is Dawn Phenomenon. I call it Darn Phenomenon (DP). Dr. B talks about it in his book and basically advises insulin to address the issue. It basically happens as your body clears circulating insulin the early morning hours and then releases stress hormones (like cortisol) to help you rise. Too little insulin in the face of blood sugar being dumped from stress is a recipe for a blood sugar rise. Many of us have much, much worse DP.

I always found that not eating made it worse and that if I just ate right away, like a couple eggs I could at least stop further rises in my blood sugar.

Brian explained it perfectly. I keep a pre-filled syringe with 1.5 units of humalog on my nightstand and inject the second I become conscious in the morning. This usually keeps my DP at bay. I try to never skip breakfast too, as this can exacerbate it.

Metformin should be helping not hurting your numbers. I generally have better morning numbers if I don't snack in the evening. I don't always follow this advice but it generally holds true. I believe Dr. B recommends eating as soon as possible upon rising.

Sounds exactly like Dawn Phenomenon, but also be aware that infections can raise BG, even something as minor as bleeding gums. Something to take into consideration...

I don't want to take insulin to force my BG down. Insulin has side effects. Assuming that metformin is not causing the slightly high BG, which seems the consensus here, I'll wait and see if morning BGs continue to lower. Thanks.

Last week I was getting over a cold. Perhaps that is still having an effect. Thanks.

When you do have an elevated morning BG, what kinds of snacks caused it?

I don't quite understand this in that if your beta cells can't react to prevent the glucose released at dawn (via the mechanism as Brian described) then surely you should be high after meals too (as the beta cells should not be able to react to glucose from food either)? If so it sounds like you are a diabetic who needs more than a low carb diet and metformin to control it. Low carb diets can increase resting blood glucose at least initially (I don't know quite how, I think the ketones/fatty acids make cells physiologically insulin resistant so the little sugar there is is saved for the brain and bits that need it). On the whole tho, any rise should probably only get to 90 (5mmol) or so (???) so I don't think it is that and after longer time, in me, this (physiological) insulin resistance seems to settle and things return to normal. Other thought is that if it is just in the mornings that your BG goes up, would long acting (modified release) metformin taken at night help control that? Regards

All kinds, although always stick to low carb. The best for me is none, although It does seem that chocolate milk made with almond milk and sweetened with Truvia does not cause a problem.

Since everyone's diabetes is different the best course is frequent testing and then seeing if a pattern emerges.

I have read folks saying a green apple before bedtime or cheese or protein helps. For me they were ineffective but that doesn't mean they would be ineffective for you.


When I snack before bed, it is usually a slice or two of thin swiss cheese, some sunflower seeds, or a cup of bullion. Sometimes I have a high-carb snack, but this is always within my total, so it might be just 1 or 2 grams of net carbs. For example, I might have half of a York Peppermint Patty, or a small cracker, or a teaspoon of apple sauce. I can't believe that such a small snack would cause my BG to rise in the morning. But I can experiment and find out.

what used to keep your BG down was insulin anyway! (admittedly from your pancreas directly into your portal system and turned off automatically so no risk of hypos) and raised blood sugar long term also has side effects! However I guess need for further action depends on your HbA1c result which will assess whether your blood sugar is raised long term or not (especially if your raised BG's are a short term change from an infection etc as suggested below hence will settle alone). Of course, if needed, there are other treatments before insulin.. Best wishes

It is my understanding that an individuals insulin resistance varies depending on if the bodies store, of insulin, in the form of glucogon is depleted or topped off.

For myself my highest reading is invariably in the morning after breakfast and my lowest is my pre evening meal reading. I interpret this as lack of physical activity during sleep has not used any of my bodies stores and so my insulin resistance is high in the morning. Even minimal activity during the day depletes my reserves and lowers my insulin resistance.

You can use this to your advantage, my breakfast is usually less than 2g of carbs. My evening meal can have quite a few more carbs without resulting in a spike.

Thanks! This makes sense, and is kind of what I naturally do.