I keep reading anecdotes of people saying that their blood sugar ROSE over time on an LC diet. Many in LC community dismiss this as "physiological insulin resistance"....but high blood sugars are bad regardless of how they get that way, no?

My hunch is that most people on LC see vastly BETTER blood sugars over long-haul, and that those who see rise over time are in minority. At least I sure hope that's the case, because I'd hate to think LC could mess up blood sugar levels over long-haul.

What say you guys about this apparently not totally uncommon phenomena in LC circles?

This article over at Ketopia is what piqued my interest about this issue.

http://ketopia.com/high-blood-sugar...and-metabolism/

I don't think I've heard of that. What I have seen happen is that people will say their BG is going up while they are on a LC diet, but if pressed, they will admit to carb creep. I don't know about non-diabetics, but for diabetics the amount of food makes a difference. I can be eating very LC foods, but if I eat too much my BG will rise. Also gastroparesis (which I recently found I have) will elevate BG at odd times, as will illness. I'm not checking my BG right now as I have a bad cold & my BG is just too depressing. But I know I'm eating right.

I should admit that while I read the article, I didn't understand a lot of it. I'm not very sciencey.

Interesting article, Coach Jeff, at least what I could make sense of. I was not able to blow up the graphs enough to read what I was looking at, but the text was mostly understandable.

I've been eating Low Carb for 10 years and VLC (<50 grams total per day) for around 4. My fasting glucose was always great, but A1c began running strangely high (5.7-5.9) about 7 years ago. Neither raising nor lowering carbs seemed to change it much.

And then about a year ago, my fasting glucose began to rise. My doctor ran my fasting insulin levels, expecting to find high levels, but instead it was the lowest level of normal (5 on this particular scale, with 30 being really high). I'm assuming it is physiological insulin resistance.

I've been keeping conscientious track of my FBG and PP levels intermittently for about 6 months. If I eat 3 moderate meals a day, fasting glucose is in the 90s or low 100s; PPs are seldom above 120. If I skip a meal or otherwise IF, my glucose levels go down to the 80s, but sometimes PP will go as high as 130. I'm not sure I understand quite what is going but I intend to read your article a few more times to see if something clicks.

Something that pops out for me on those graphs is that they show fasting insulin going down on whatever version of a low fat diet was used, and up on the high fat diet. I don't consider this as evidence against a high fat diet in general, but against specific high-fat diets. I do better on an 80 percent fat diet, near null carbs, than I do on a 40/30/30 carbs/fat/protein mix like the Zone, but that doesn't make fat innocent--it doesn't mean a 30 percent fat diet is better than 15 or 20 percent fat diet, like the one lots of Asian cultures were eating until fairly recently. I'm better off eating some butter with my steak, than a potato--but I'm not convinced I'm better off eating some buttered potato with my steak than a plain potato with my steak.

http://www.ncbi.nlm.nih.gov/pmc/art...t00221-0045.pdf

I was reading this rat study yesterday. Rats, fasted 24 hours. Given a glucose dose that would quadruple their insulin levels at the twenty minute mark if they hadn't been fasting for two days, their insulin barely budges. Very slight increase in insulin, glucose just goes up around where it normally would at twenty minutes--and stays there for hours.

The explanation given, and it seems reasonable, is that in order for glucose to stimulate insulin secretion in beta cells, the glucose given needs to stimulate an increase in ATP production in the beta cells. During starvation, various tissues adapt to fat metabolism, sparing glucose for the brain--this includes pancreatic cells. I've seen studies where this failure of the insulin response to glucose can be obliterated if animals are given niacin--niacin shuts down lipolysis, and once free fatty acids aren't available for fuel, cells are forced to return to glucose as a fuel (assuming it's available).

Jeff, I could write volumes trying to answer that question, but net down, I still dont know what to do about my higher BG readings! I am a classic case of this long term reaction to VLC, have read every article written on this phenonema, including Peter's long explanations at Hyperlipid, but currently feel more uneasy about this than previously.

My FBG has climbed from 80s pre-LC, to 100s at 2 years, to 120s at 4 years. When my first lab test went over 100, I was assured it wasn't problematic and HbA1c was a better indicator for those in nutritional ketosis.
Well now at 4+ years LC, that test is also in the pre-diabetic range. I am reading so much new info on gut microbiome and need for prebiotics, that I am testing the addition of fiberous vegetable and fermented foods. I will have my A1c repeated in Feb, but GPs don't buy the "it's a complicated relationship" when in "nutritional ketosis" theory that the LC doctors use as the explanation. I don't think my below normal fasting insulin, and mine has been UNDER normal, around 1.6, balances out a three month indication of high BG. So since Sept, I have been upping my carbs, and with some recent holiday meals, not in a good way.

Currently reading Bulletproof Diet only since the library ordered it, not a big fan of Asprey. But he drops in comments about this problem a few times at random (need to go back and find them again). His suggestions are to eat more carbs at dinner, and to have some version of a "carb re-feed" once a week. Not go crazy with it, but states without much background provided, as many others have recently, that continuous very low carb causes higher blood sugars. Dr. Davis has added to his program about feeding the gut micro biome with real food starches. Dr. Sarah Ballentyne's recent interview with Jimmy Moore brought up this issue around the 1 hour mark. The entire podcast was good "food for thought", but her comments about VLC exchanging one metabolic inflexibility for another, was spot-on for me.

And here's a completely anedoctal observation from knowing other long term low carbers, it seems to me that people who had high blood sugars, or were diagnosed diabetic before LC, continue to have fantastic BG control after years on LC. Those like myself who did not have problems previously (or at least it never showed up in a FBG test, so never had an HBA1c) do see this physiological insulin resistence more often. Maybe a result of these genetic markers in the Ketopia article you posted? Whatever, high blood sugars are bad for me, so now trying to find a way to un-do them.

Yeah, the progressively higher blood glucose numbers sounds like something to look for. If your blood glucose had just gone to around 100 mg/dl and stayed there, that could be chalked up to physiological insulin resistance. If it keeps getting worse, not so much. Free fatty acids go high enough to provoke insulin resistance within days of going on the diet, that can't explain a progressive worsening.

And insulin that low with high blood sugar doesn't sound like insulin resistance, it sounds like resistance to secreting insulin.

I know Alan Aragon...who you may be familer with (very popular nutritionist within hardcore fitness circles) says excess saturated fats really and truly does interfere with proper glucose handling and insulin sensitiivty.

I used to dismiss that idea, one which Weston Price Foundation "debunked" over 10 years ago, as propaganda from fat-phobic mainstream types...but perhaps it's true.

Heck even Cordain is STILL very insistnent that certain sat-fats are a problem.

I really don't know for sure.

As they say, the more you learn about diet, the more confused you seem to get at times.

JEY100 - I would have to agree that increasing FBG really is NOT likely to be an "ok" part of following an LC lifestyle. It does seem that it's FASTING sugars that rise on many LC folks....yet somewhat paradoxically their A1C tends to get better a lot of the time. (Though some do indeed report that even the A1C rises.) Also very interesting that diabetics see their sugars go DOWN very predictably, whereas those who LC for other reasons sometimes see theirs go UP over the years.

I am a lifelong sufferer of hypoglycemia, and a reduced carb diet is the ONLY thing that fully controls it, so will never go high carb of course. But I find my body seems to reject very low carb....I am too hungry on VLC/HF for some reason. I feel better and have better satiety on higher protein and carbs around 70 to 75.

It's worth noting that several doctors, including the Life Without Bread author, put patients on about 70 grams of carbs a day, rather than mega low. I wonder if trial and error showed them that "side effects" like we're talking about here could be avoided at slightly higher carb levels?

It's also worth noting that I've seen several people, who saw their FBG RISE on long-term VLC/HF, report that this issue seemed to go away when they dropped all dairy from the diet. Which kinda makes sense from an evolutionary viewpoint...that many humans would do better WITHOUT neolithic dairy on thier LC plan?

But man oh man...LC without dairy would be tough for me to follow. I'd have to be real certain it was necessary to be motivated enough to go that way. I do not drink milk, and eat very little dairy...but I do like a bit to make my LC diet more tasty.

Would the "Dawn Phenomenon" at all account for why morning fasting sugars are high in some? I hear diabetics mention this, but not actually sure what it is.

This has been a discussion for years.

There was this raw meat guy who saw this, can't remember his name or what the outcome was. He had been eating nothing but raw meat for years.

Anyway, many peop have had this experience over the years and there's been stuff written about why this exists and why it's okay.

IMHO, it's never okay. Blood glucose is blood glucose no matter where it comes from. It's still glucose!!

I think it more likely to occur in ZC (or VVLC). That has been my personal experience.

There's no way of knowing unless you are testing or if your labs are showing BG over 100 on a regular basis.

These numbers don't go to extreme levels but can hover around 110.

Oh, yes, I think it's dawn phenom that most of these peop are experiencing.
Some years ago there was some discussion on the ZIOH forum.

First, I think the reason why diabetics' FBGs come down when they go low carb is because most of these people, even those under standard 'treatment' for their disease, are eating a lot of carbs. If they are not being treated, their BGs can run way up in the hundreds. If they are being given standard medical advice they are still eating lots of carbs, and trying to control their blood sugars with various drugs and insulin. Going low carb immediately eases the situation, and their BG goes down nicely. I'd be very interested in whether their blood sugars start going back up after years of low carb eating.

I think the Dawn Phenomenon accounts for much of the rise of fasting blood sugars in VLC eaters. Fasting blood sugars are measured in the morning after all, and I am one of those whose early morning readings are in the 120s after having eaten LC for several years. If I wait until 10:00am or so, my BG looks much better. Right now it's running at about 97.

So, the last time I went to my doctor for a checkup, just a month ago, I had a choice as to what FBG I wanted to show him, depending on when I showed up at the lab. I chose to go for my blood draw early, and so got a reading of 126. He's now convinced I'm a Type II. I'm not so sure. My HbA1c is not so good though, so he may be right. In any event, I've added some IF to my plan to see if that does any good for the FBG.

This is a very interesting topic, and one that does make me uneasy about my dietary choice. Something is not right here, and I'd sure like to know what it is.

ETA: I wonder if having slightly high FBG but with low insulin levels is a good thing. I've read that high insulin levels are as problematic as high BG, but I'm not sure what is worse, high fasting blood sugars or high insulin.

Seems obvious that having both is the worst of all worlds, but maybe having slightly elevated FBG for a couple of hours in the morning, but with low insulin, is actually a good thing.

This is what I'm thinking as well. I've been heavily influenced by Dr Jason Fung's blog this year and he definitely thinks high insulin is worse than high glucose levels, that it is the insulin that does most of the serious damage to the body. Using his IF methods (though modified because I'm a wimp and can't seem to fast for a full 24 hours, much less 36), I'm bringing my FBG down to normal levels.