In the next two articles we’re going to discuss the concept of “normal” blood sugar. I say concept and put normal in quotation marks because what passes for normal in mainstream medicine turns out to be anything but normal if optimal health and function are what you’re interested in.
Here’s the thing. We’ve confused normal with common. Just because something is common, doesn’t mean it’s normal. It’s now becoming common for kids to be overweight and diabetic because they eat nothing but refined flour, high-fructose corn syrup and industrial seed oils. Yet I don’t think anyone (even the ADA) would argue that being fat and metabolically deranged is even remotely close to normal for kids. Or adults, for that matter.
In the same way, the guidelines the so-called authorities like the ADA have set for normal blood sugar may be common, but they’re certainly not normal. Unless you think it’s normal for people to develop diabetic complications like neuropathy, retinopathy and cardiovascular disease as they age, and spend the last several years of their lives in hospitals or assisted living facilities. Common, but not normal.
In this article I’m going to introduce the three markers we use to measure blood sugar, and tell you what the conventional model thinks is normal for those markers. In the next article, I’m going to show you what the research says is normal for healthy people. And I’m also going to show you that so-called normal blood sugar, as dictated by the ADA, can double your risk of heart disease and lead to all kinds of complications down the road.
The 3 Ways Blood Sugar Is Measured
Fasting blood glucose
It only tells us how blood sugar behaves in a fasting state. It tells us very little about how your blood sugar responds to the food you eat.
Up until 1998, the ADA defined FBG levels above 140 mg/dL as diabetic. In 1998, in a temporary moment of near-sanity, they lowered it to 126 mg/dL. (Forgive me for being skeptical about their motivations; normally when these targets are lowered, it’s to sell more drugs – not make people healthier.) They also set the upward limit of normal blood sugar at 99 mg/dL. Anything above that – but below 126 mg/dL – is considered “pre-diabetic”, or “impaired glucose tolerance” (IGT).
Oral glucose tolerance test (OGTT)
The OGTT measures first and second stage insulin response to glucose. Here’s how it works. You fast and then you’re given 75 grams of glucose dissolved in water. Then they test your blood sugar one and two hours after. If your blood sugar is >140 mg/dL two hours later, you have pre-diabetes. If it’s >199 mg/dL two hours later, you’ve got full-blown diabetes.
Keep in mind these are completely arbitrary numbers. If your result is 139 mg/dL – just one point below the pre-diabetic cut-off – you’ll be considered “normal”. Of course this is perfectly absurd. Diabetes isn’t like catching a cold. You don’t just wake up one day and say, “I’m not feeling so well. I think I got a bad case of diabetes yesterday.” Like all disease, diabetes—and diabesity—is a process. It goes something like this:
malfunction > disease process > symptoms
Before your blood sugar was 139, it was 135. Before it was 135, it was 130. Etcetera. Would you agree that it’s wise to intervene as early as possible in that progression toward diabetic blood sugar levels, in order to prevent it from happening in the first place? Well, the ADA does not agree. They prefer to wait until you’re almost beyond the point of no return to suggest there’s any problem whatsoever.
[End rant]
The other problem with the OGTT is that it’s completely artificial. I don’t know anyone who drinks a pure solution of 75 grams of glucose. A 32-oz Big Gulp from 7-11 has 96 grams of sugar, but 55% of that is fructose, which produces a different effect on blood sugar. The OGTT can be a brutal test for someone with impaired glucose tolerance, producing intense blood sugar swings far greater than what one would experience from eating carbohydrates.
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Hemoglobin A1c
Hemoglobin A1c, or A1c for short, has become more popular amongst practitioners in the past decade. It’s used to measure blood glucose in large population-based studies because it’s significantly cheaper than the OGTT test.
The higher your blood sugar has been over the past three months, the more likely it is that glucose (sugar) is permanently bonded to hemoglobin.
The problem with the A1c test is that any condition that changes hemoglobin levels will skew the results. Anemia is one such condition, and sub-clinical anemia is incredibly common. I’d say 30-40% of my patients have borderline low hemoglobin levels. If hemoglobin is low, then there’s less of it around to become bonded to glucose. This will cause an artificially low A1c level and won’t be an accurate representation of your average blood sugar over the past three months.
Likewise, dehydration can increase hemoglobin levels and create falsely high A1c results.
The “normal” range for A1c for most labs is between 4% and 6%. (A1c is expressed in percentage terms because it’s measuring the percentage of hemoglobin that is bonded to sugar.) Most often I see 5.7% as the cutoff used.
In the next article we’ll put these “normal” levels under the microscope and see how they hold up.
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Hi I need to know if my readings on the glucose meter are normal or if I should worry and test further . I am not diabetic but don’t ever want to be either .I woke up and did not eat and testes at 88 ate lunch drank juice and water testes two hours later and was at 132 is this normal for non diabetic ? Please help ?
Hi Angela, your reading of 132 @ 2hrs after food is probably absolutely fine, but I does depend on what you ate. If it was a high or moderately high carb meal, then 132 is OKish, if it was a low carb meal then 132 is in the zone to start looking at your diet. Ideally you should be back down to around your start point at 2 hrs. Try testing at 45mins to 1hr after food to see if you are getting high spikes (over 160), if you are then start to look at your diet and make improvements. Remember that its mainly carbs that raise BG levels, high GI will spike you earlier, around 30-45 mins, low GI will spike you later, anything from around 1hr30 to 2hr30. Once you can see if there is a problem, you can work out what it is and make adjustments. Ideally you should remain below 140 all the time, but a brief excursion to 160 will not cause you any damage as long as its not too often or for too long.
I am healthy man some times my fasting blood suger come under 100 after 11 or 12 hours when i take sugar food when no sugar food then after 8 hours it comes down 100 while i am healthy man of 58 please give me advice
Hi Chris,
So my concern is I have been feeling tired after meals for the past week. I had gestational diabetes with my son born a year ago, but my sugar levels went down right after birth. Now I have been using my accucheck meter to see if this is why I have been so tired. My fasting glucose has been in the range of 109-117 in my left hand over the last 3 days but my 2 hour post meal is 154 from the left hand and 110 from the right. The range is so large. The test strips and machine are all the same. I believe if I checked my fasting on my right hand it would be lower too under the 99 mark. Do you think the other tests will help give me a better idea if I am actually Pre-Diabetic or not?
I’d been having blood test regularly for a lot of years…then suddenly I was told I was diabetic….I couldn’t understand why nobody realized that my blood sugar reading was getting higher…..diabetes doesn’t just happen suddenly…..I had no symptoms….no thirst….no weight loss…..but I was taking statins for years……now …they tell us that statins raise blood sugar and can cause diabetes……I stopped the statins…..my b.s has come down….and my dr. is very pleased with my a1c results….he says they are as good ///if not better than some non diabetics….he’s not pleased that I stopped the statins….
i’m obese and was diagnosed DIABETIC 2 years ago, but drastically reduced my carb intake and brought my fasting bg readings down to 74-84. However, I got lazy and started eating poorly, and gained weight back (i lost about 60 pounds in the dieting process). So fearing the bad news from the dr., i’ve started back onto my good habits and my post prandials (2 hrs) are around 105-115, but my fasting never seems to drop under 90 (though it has stayed under 100)… anyone have any advice or thoughts on this?
Need advice…I had a 20 hour fast yesterday and after 18 hours my bg was 3.3, I felt awful, however was told this is normal, it keeps happening where I keep feeling low after about 4 or 5 hours of eating. I bought a home monitor and when i was discharged from hospital I was given a sanwhich and some orange juice, went home and tested one hour after eating and it was 11.7 is that normal? Please help this is all new to me. I have done a previous 12 hour fast and my bg was 2.6!
Great blog. Thank you for providing this information.
I went for a JOG not a job.
My glucose was 230 this morning. I read the comments herein and went for a job at 10am. When I got back my gl was 190. Still high but it showed me the way! Thank you!
So I feel nervous with what I’ve read. I have recently been getting really sick, dizzy nauseous shaky those things. I went to the dr and they drew my blood and have a blood test thing to me for the next 10 days or so. My first two readings 1 when I had eatin maybe 20 minutes prior was 139 and a few hours later now. I’m feeling sick again and tested at 110… What are some solutions to save myself? I know 139 is bad… I don’t understand though why I feel so sick at 110? I don’t know if I’m asking my question well but I’m very worried and just don’t want to end up with diabities… I’m a 24 5’9 and 170 pounds female who is trying to be smarter with my food choices…
Any advice or some explanations? Is dropping so fast a bad thing too?
Thankyou!
Hayli
Hello,
I have read many post but yours caught my attention. I am a cna and work with diabetic patients. My mother n law is also a diabetic and I have to keep a close eye on her. Normal levels range from 70-140 you can push it a little as long as it doesn’t go over 200. I have done lots of research on this subject however, everyone is different I have found. One of my patients can have glucose readings that just reads hi then 1 hour later she is bottom out on me. The best advice I can give you is to know your body test yourself before breakfast and an hour later. Eat small portion meals frequently. For example 3 meals a day maybe 3 small snacks. A half a peanut butter sandwhich and 1 cup of juice should help hold your sugar through the night. If you have problems with waking up with low sugar set your alarm at night for 3am drink a cup of juice if to low it does’nt hurt to add a spoon of sugar or eat spoon of jelly to get it up if around 40. It is a proven fact every diabetic sugar drops at 3am. I wouldn’t worry about sugar levels at 139 that is good. My patient would go to bed with sugar levels around 180 and at 1am drop to 70 at 3am to 40. So everyone is different some are more sensitive than others. You shouldn’t be having problems with your sugar being at 110 but that doesn’t mean its not possible.
I have no family history of diabetes, I have always been a big guy, 6ft and 280 lbs. Recently my wife has been testing her blood sugar levels and for fun I decided to do mine. My glucose levels have been from 300 to 600 within the past two days every time we test. I test before meals, after meals, after fasting for 4 hours. we also bought a ac1 test and mine came to 11%. any ideas, am I diabetic?
Tim – Those numbers would definitely be classified as diabetes. And 300-600 mg/dL blood sugar is dangerously high. You could potentially have Type 1 diabetes, which is an autoimmune condition that destroys the pancreatic cells that produce insulin. Either way, you need to see a doctor immediately.
hi there I have a reading of 135 is this a prediabetic level ??? many thanks
Surely if your fasting BG level is low it means that your are not particularly insulin resistant? Virtually everyone that I know that has insulin resistance has a high fasting BG. The fact that you are producing loads of insulin indicates that you are insulin resistant. I have really low fasting BGs, but spike really badly after consuming more than about 20g of carbs simply because I now don’t actually make much insulin and so cannot cope with any more than that small amount of carbs. If you are insulin resistant wouldn’t your BGs stay high because the insulin that you are producing is basically ineffective?
Hi Veronica, what I’m trying to say is that I’m severely insulin resistant and confirmed by an NMR LP-IR score of 67 and sky-high fasting insulin level. My functional doc has told me that if my pancreas is still very efficient (so I’m not a diabetic) at churning out the insulin, then it’s able to keep my blood sugar normally low. It means that if there are two cars going the same speed down the highway, one car would be going at 10,000rpm (my pancreas) and my blood sugar would be cruising along nicely at 3,000 rpm. So my point to you and Chris, are you not missing out on the fact that some (or maybe a lot of) people may not be properly diagnosed as insulin resistant because they’re blood sugar is normal and healthy, but since the medical practitioner never checked the fasting insulin (or NMR), we could be missing the diagnosis! Check out this video of a wrestling coach who had great fasting blood sugar and normal basic cholesterol numbers. But guess what they find out when they dig deeper and find out he’s severely insulin resistant and is at amazingly high risk of cardiovascular disease: http://www.youtube.com/watch?v=an6L9VY0v8A
Couldn’t agree more Howie. If you are insulin resistant, and still producing lots of insulin to compensate, then you are effectively wearing out your pancreas. So, yes, I am sure that there are many people out there that are not being diagnosed. I’ve got the other problem of not producing enough when I eat food, so 20g gives me a huge spike, but, funnily enough 75g of glucose doesn’t have any effect on me ! ! an annommaly I know. Most of the time I don’t actually produce enough insulin, hence very low c-peptide, but if I take glucose then I produce insulin ! So far, no-one has been able to give me a sensible answer on that one.
Isn’t fasting insulin a far superior measurement of insulin resistance than blood sugar, which is what we’re really concerned about? A lot of people will have “good” blood sugar levels of 80 or below (like me), but my fasting insulin is around 9 uIU/mL (good is below 3). I have ragingly high insulin levels that are keeping my blood sugar down, so as a clinician, do you not worry that you’re missing the whole story? Love what you do and thanks for letting me have a voice.
Howie–How do you correct insulin resistance? Is it meds or diet? Could you elaborate. Think I may be dealing with this–and causing hypoglycemia issues
insulin resistance? meds or diet?
Either, both. Depends on whether you’re willing to make lifestyle changes or would rather take the pharma route. Without “control” it only gets worse.
Hi Chris,
It is really helpful to read your blog.
I have family history of diabetes. My mother has it at the age of 52
My age is now 30. I was overwight for 2 years during and after pregnancy (80 kg. my height is 5.5). I reduced my weight to 60 in 2012 but I have put on again 5 kgs. now I am 64-65 kg. I tested my FBG using home glycometer it was 94 and 99 on next day. my post meal BG was 104. I am worried that I either have prediabetes or diabetes because of family history and my reading.
2-3 years back these readings were FBG 75 and Post meal 95.
are home glycometers correct? am I at high risk for diabetes?
Hi Chris
I have had a sweating problem all my life. I have been told that I have an over-active sympathetic nervous system but thought it might be related to blood sugar levels. I had some fasting tests done and the only reading I can remember was Hemaglobin (I think) of 4.3, which is apparently normal. I, however, get thrush at the slightest intake of any sugar, I’ve probably had thrush hundreds of times and so now I do not consume any sugar at all. Do you think, that my sweating problem could still, somehow be related to something to do with my blood sugar? Please help
Thank you for this article. Question. I am not overweight, I exercise and eat pretty darn clean 80% Paleo. My A1C levels have been 5.6 then with diet change 5.4. To me, this is not acceptable. My doctors response is exactly how you described above. I do have thyroid problems but seem to be Ok with levothyroxine and cytomel. I have terrible chronic back pain. I also have pretty bad IBS/leaky gut. My naturopath told me I do not detoxify efficiently. I take milk thistle now and chlorophyll. Do you recommend anything to help detoxify. Any shake or supplements that help? How can I get these sugars down?? Please help?
Great website sent it to my daughter’s who are experimenting with paleontology diet. My glucose runs between about 118 to 140 daily a.m. testing but I have a 5.5 A1C …it was at 6 …and highest 6.5 according to a.m. fasting test I have diabetes (diagnosed in 1984 along with bells palsy…have had 7 cases since then) the other test I don’t. I watch my diet well as I have other neuropathyies. Drs (neurologists etc)scratching thier heads. One point agent Orange was dropped right on top of me and my team on several different occasions in Vietnam. VS says I have diabetes with palsy as secondary. Can I have at times diabetes and at other times not have it. Can it go into a prediabatetic state? Bottom line can it appear to be cured of can it be cured with diet and exercise. Thks you are really doing a service here…
Hi , i hav a question, i had a fasting blood test. Only thing is because i was vomiting daily i didnt fast properly. Now my G.P is sayin i hav diabetes as my report came bak wid sugar level of 9.8 . What i want ti know is , is this accurate ? Is ther any thing i may not b diabetic ? Im a bit confused
Chris, I respectfully disagree with your criticism of the glucose tolerance test, although its true that “real world” diets do not reflect it, that’s the point, with so much variation in diets, the glucose tolerance test is neutral, a person who for instance does poorly but in real life conditions and diets is okay, is not indicative of the person doing fine, rather the person’s diet may be different, and they have delayed syndromes due to their gut or other factors, for instance if a person’s body slowly converts carbs more than others to glucose, that isn’t indicative of the test’s unreliability. Similary if a person passes the test, if could mean they have other problems, for instance dr. bernstein in his talk about the “Chinese vegetable effect” states that eating even a small vegetable can cause an increase of blood sugar because of the mismatch between glucagon and insulin.
So regardless of these factors and whether folks are more sensitive to wheat, carbs, and other foods, the glucose tolerance test is a neutral factor, simply to measure how the body tolerates the end product of carbohydrates and proteins, glucose.
Just because a person’s diet and body are different doesn’t make the test irrelevant or “artificial” because other factors influence the result.