My husband finally got onboard with low carb and has been doing it for the past nine months, except for some cheating on holidays. He likes it and has lost about 40 pounds. He recently started testing his blood sugar and was shocked to discover how high his fasting BS is. I've read up on it, and know that low carb can cause higher fasting blood sugars, but this morning his was 131!

Any ideas? Advice?

If he's only recently started testing his blood glucose, when already low carb--you don't have a baseline. You could have him test his blood glucose while on a stint of a higher carb diet, I guess. Typically I hear about low carb putting somebody around the 90-110 area, if it gives them higher fasting blood glucose.

A few possibilities. One, sometimes a box of strips just sucks, I once had my fasting blood glucose testing near the prediabetic range, that lasted as long as that box of strips.

Another possibility is that his blood glucose was already running high. You don't really know if his fasting blood glucose is running higher on low carb--it might even be running lower than it was before low carb.

What are his postprandial blood sugars like? If a low carb meal doesn't move them that much, that's probably a good sign.

His fasting blood sugar at the doctor last year, before low carb, was 97. And he did a test that came with the meter...apparently the strips are fine. I'll ask about his post-prandials. Thanks for the suggestions.

Could be the Dawn Phenomenon or Somogyi effect - check out:
https://my.clevelandclinic.org/heal...-in-the-morning

Also, some BG monitors require recalibration whenever you start a new package of strips.

Since he doesn't have diabetes, I didn't think those applied.

Does he have fatty liver? (Answer: If he's overweight, his liver is fatty, even if he's not yet symptomatic. That's the first place your body starts stashing excess carbs, before it turns it into fat everywhere else.)

When I started testing, I was really upset/confused by this, too. But his liver is finally being free to dump that glycogen (which is then converted into glucose).

IF helped me get my fasting BG numbers back where they should be. (I didn't start until 3 or 4 months back on the LC wagon, when my hunger went away. At that point, IF became easy.)

The Diabetes Code by Dr. Fung helped me understand a lot. (I was able to borrow an e-copy from my library, using Hoopla. Great if you're impatient. )

I think intermittent fasting might be a good option for him. Even before low carb he never had a problem skipping meals. I will suggest it. Thanks!

Sources of blood sugars are food(protein, carb, fat), Glycogen, body protein breakdown and fat breakdown.

Just don't know why there is a demand of blood sugar? The only part of body we know of that needs carb is brain. Carb created by body is enough to cover that already. This is why people keep calling keto diet.

You can try no carb for couple days to weeks to see the blood test results. If it is food, then you can relax. You just need to adjust the ratio of food.

Thanks. This morning he had 105, which isn't too bad. Didn't really make any changes. But I'll pass on the advice.

And since he has been Keto for nine months already, and successfully lost weight...it may be normal "Adaptive Glucose Sparing" Read about that, and a few other possibilities at:

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

That was my first thought, Janet, but 130 seemed quite high, even for adaptive glucose sparing. It's down a little now, and I'm thinking it might have been stress...I don't know. Thanks so much for you input.

How is your husband's blood sugar now?

About the same. He was 124 this morning.

It was not unusual for my BG to be higher in the morning. It would change over the course of the day and was normal after meals, so I attributed it to dawn phenomenon. After 18 months or so, I had my HbA1c tested and was at 4.9, so over the 3 months prior to the test, I was in a good zone. That's why I attributed those morning highs to dawn phenomenon. Sometimes it takes a while for the metabolic responses to adjust even after going strict keto. It's typically a lag effect.

That’s really good to hear - 4.9 is amazing.