So Called "Normal Labs" are NOT Healthy

Dr. Eric Berg DC| 00:17:30|Mar 22, 2026
Chapters6
Normal labs can be misleading because “normal” often means average in a population that's metabolically unhealthy. The chapter argues that many patients are misdiagnosed or dismissed and previews key lab values and concepts worth understanding.

Normal lab ranges aren’t health; Dr. Berg explains why insulin, A1C, and vitamin D testing, plus smarter lipid and cortisol profiling, reveal hidden risks.

Summary

Dr. Eric Berg challenges the comfort of “normal” lab results, arguing that average values in a metabolically sick population don’t equal health. He deconstructs how reference ranges shift with population trends and highlights pivotal tests many doctors overlook. Berg emphasizes fasting insulin as a critical early warning—often rising long before glucose does—and introduces HOMA-IR as a practical tool to gauge insulin resistance. He explains why A1C provides a long-term view of blood sugar and discusses dawn phenomena, liver glucose production, and the benefits of low-carb, intermittent fasting strategies to normalize morning readings. The video also dives into the limitations of standard mineral testing and the importance of speciation tests for potassium, magnesium, selenium, and zinc, plus a more nuanced look at B12, MMA, and homocysteine. On cholesterol, Berg argues that total cholesterol isn’t the enemy and urges a focus on LDL particle size (Pattern A vs. Pattern B) via advanced lipid profiling. He covers cortisol testing, recommending saliva-based profiles or HRV as a noninvasive proxy, and argues vitamin D testing should assess cellular activity using parathyroid hormone alongside 25(OH)D levels. To harden the case, he cites historical shifts in normal ranges (glucose, prediabetes, and cholesterol) and warns against complacency with CRP, advocating anti-inflammatory strategies and mineral-focused testing. The overall take: to truly know your health, you need targeted, tissue-relevant biomarkers and a proactive, nutrition-first plan rather than relying on broad reference ranges.

Key Takeaways

  • Fasting insulin is a crucial, often-overlooked test; levels between 2 and 6 μU/mL suggest healthier insulin sensitivity, while 8 signals concern and 10–12 indicates high risk for insulin resistance and diabetes.
  • A1C provides a three-month glucose average (dashboard view) that can reveal hidden trends even when daily glucose looks normal, especially with weekend carbohydrate spikes.
  • HOMA-IR combines fasting insulin and fasting glucose to assess insulin resistance, catching problems when glucose remains normal but insulin is elevated.
  • Vitamin D levels alone can be misleading; a normal 25(OH)D with high parathyroid hormone (PTH) can indicate cellular deficiency, suggesting higher target levels (50–70 ng/mL, sometimes higher for therapeutic goals).
  • LDL cholesterol guidance should distinguish Pattern A (large buoyant particles, less risky on low-carb diets) from Pattern B (small dense particles, more atherogenic); a specialized lipid profile is essential.
  • CRP should be near zero; values like 1.5–2 indicate low-grade inflammation, which is not “normal” and should be addressed with diet, sleep, and omega-3s.
  • Insulin resistance is a liver and pancreas issue driven by high carbohydrate intake; reducing carbs and employing intermittent fasting can reverse dawn phenomenon and lower morning glucose via lifestyle changes.

Who Is This For?

Essential viewing for anyone on a low-carb or ketogenic path, people curious about why standard “normal” labs may miss early metabolic disease, and those wanting a deeper understanding of insulin, lipid profiling, and vitamin/mineral testing.

Notable Quotes

"Your labs are normal. That is probably the most dangerous phrase in modern medicine."
Berg opens by challenging the meaning of 'normal' and its danger in medical decision making.
"Insulin is removing sugar from the blood. The test that is the most important that doctors should be doing is a fasting insulin test."
Highlights fasting insulin as a critical, often neglected biomarker.
"The normal level of fasting insulin? There is no agreed upon number. So I’m just going to give you my two cents."
Acknowledge lack of consensus and present his threshold guidance.
"HDL and LDL are not the whole story; there are Pattern A and Pattern B LDL particles and you need a specialized lipid profile."
Explains particle size distinction and why a basic cholesterol test is insufficient.
"Vitamin D looks normal, but parathyroid hormone can tell you if vitamin D is actually penetrating the cells."
Describes cellular vitamin D activity and the role of PTH in interpretation.

Questions This Video Answers

  • Why is fasting insulin a better early detector of metabolic issues than fasting glucose?
  • What is HOMA-IR and how do you calculate it from fasting tests?
  • How can you interpret A1C in the context of weekend carb spikes?
  • What’s the difference between Pattern A and Pattern B LDL, and why does it matter for heart disease risk?
  • How should I test vitamin D beyond a standard 25(OH)D level and what does parathyroid hormone tell me?
Dr. Eric BergInsulin resistanceFasting insulinA1CHOMA-IRDawn phenomenonLow-carb dietIntermittent fastingCRPCholesterol profiling (LDL patterns)
Full Transcript
Your labs are normal. That is probably the most dangerous phrase in modern medicine. Do you know why? Do you actually know what normal means? It doesn't mean you are diseasefree. You are just average. And in a population where the majority of people are metabolically sick, average means you're probably in that bucket, too. I've seen this in practice for a long time. These people coming in, they do not look healthy. A lot of weight issues. They're losing hair. They have skin issues. but they come in with their blood values that are normal. Some people are told, "Oh, you know, it's all in your head." Don't buy that. I mean, the worst thing you could do to someone is give them the wrong diagnosis. And that's definitely a wrong diagnosis. Today, I'm going to show you some really important lab values. Then, I'm going to talk about some of the most important things you should know about a blood test and what you should focus on. But what happens with the blood values is just picture like a bell curve. And what they do when they create these reference normal ranges is they basically cut out the low end of this graph and the higher end. So as the population is getting sicker and fatter, these normal ranges are really coming out of that group. In 1997, they changed the normal fasting glucose level. It was 140 and then overnight they changed it to a 126 milligrams per deciliter. So before 1997 you would have to reach a blood sugar level of 140 before you diagnosed with diabetes. And then of course right at this point if you just had 126 you're a diabetic. Overnight 1.4 million people were diagnosed with diabetes. What's really interesting is that if you look at these trends or graphs of when people had a problem, you will see a lot of diabetic problems that happen over this. And if you don't know this data right here, you're thinking, "Wow, people are just eating a lot more sugar." Well, maybe, but maybe not. Maybe it's just that they changed the numbers. Also, in 2003, pre-diabetic used to be 110. Then after this date, it went to 100. Overnight, 41 million people were diagnosed with pre-diabetes after that. Again, when you're looking at trends and past statistics, you have to have all the data. And this is definitely missing data for a lot of people. And they also did it with cholesterol, too, which I think it was in the early 80s. Overnight, millions of people had high cholesterol. And then also with vitamin D. This was done just to look at the amount of vitamin D that you would need to prevent ricketetts and keep your levels at least at 20 nanogs per milliliter. when they calculated the RDAs they made an error which they never corrected even now they have never corrected this error because when they did this evaluation and said it was 600 in reality the true numbers that you need every day to keep your levels at 20 and prevent ricketetts is 8,895 international units that's a big difference right I know some doctors will even say this amount is toxic Unbelievable. If you have a vitamin D level of 20 nanogs per milliliter, that is a severe deficiency. That's just my viewpoint. I have a lot of data to back that up. But if you have 20 or less, you are probably suffering from a lot of symptoms that are related to a vitamin D deficiency. One of the biggest problems I see with what doctors test in your blood is glucose, right? They do a fasting glucose test to determine what's happening with your blood sugar. They almost never test insulin. This right here is the biggest blind spot in medicine. Okay? You can have perfect blood glucose levels, but have such a major problem with insulin, which is actually made by your pancreas. And literally your pancreas is screaming at you, but glucose is normal. So the most missing test or the test that is the most important that doctors should be doing is a fasting insulin test. This hormone right here will be elevated 15 to 20 years before your glucose starts to be elevated. So, this test measures how much your pancreas is yelling at you because insulin is removing sugar from the blood. Okay? Normally, you should only have like one teaspoon of sugar in all of your blood. And so, you can imagine an average person consumes a lot of sugar. I'm talking about 50 to 100 teaspoons of sugar per day. So, it's like working really hard. And you check your blood glucose. And the reason it's normal is because this guy is in the background working like crazy. What is the normal level of fasting insulin? There is no agreed upon number. Okay? So, I'm just going to give you my two cents on this based on a lot of research that I've done on this. You want your fasting level of insulin to be between 2 and six. If it's at 8, you should be concerned. If it's between 10 and 12, you're at high risk for developing insulin resistance and pre-diabetes and then diabetes. But some doctors when they see like 12, they're saying, "Well, that's normal." It's not. And then this leads us to the next test right here. Homir, I'm going to try to keep this really simple. Homir is doing some calculations between a fasting insulin test and also a fasting glucose test. and it gives you a little more information to tell you if you have insulin resistance. This is a precursor to diabetes. Homir is basically telling you how glucose and insulin are working together because if you really look at what's happening, right? You eat a lot of carbohydrates, you fill up your blood with glucose, and then what happens? Insulin comes in there, pulls it out, and the pancreas has to really work hard at doing this. And then the next day, you do the same thing over and over and over. Over a period of time, your body is going to compensate by creating what's called insulin resistance because too much insulin is very, very toxic. And when that happens, now the pancreas gets a signal like, oh, there's not enough insulin when there really is. So, it starts making more and more and more to the point where it starts burning out. And then now it can't regulate glucose. And so now you get pre-diabetes and then diabetes, which is literally 15 to 20 years after this whole thing started. But if you would have tested fasting insulin or even this right here, you would pick it up. But doctors never focus on that. So a lot of people ask me, "What supplements do I recommend?" Now, of course, I'm not biased of my own high-quality supplement line, but if you go to Amazon and type Dr. Bberg supplements, you'll find more information. I want to just tie in A1C. This is like a dashboard cam. So a dashboard cam is a video camera that you could play back information that happened in the past. A1C is an average of three months of blood sugar. So it's kind of taking out all the spikes and giving you an average. So let's say you eat really healthy between Monday and Friday, but in the weekends you go off and you start eating a bunch of carbohydrates. You can check your blood sugar during the week when it's great, but if you take the average from the weekends, it's going to drop it down. So, basically, an A1C is how much the red blood cell is exposed to glucose. So, this really gives you like the 10,000 foot view of what's happening. Now, since we're on the topic of blood sugar, I want to just mention this dawn phenomenon situation right here. What is that? Some people that when they get up in the morning, their blood sugar is high. Okay. But they didn't necessarily eat sugar right before that. It's high because either the cortisol is too high in the morning and cortisol mobilizes sugar or the liver itself is making sugar from other things because the person has insulin resistance. Because the insulin resistance really messes up your liver to the point where it can't really sense things correctly. So then it starts making sugar out of things that are not even sugar or things that you ate that were sugar. So here you are, you're not even eating any carbohydrates yet your liver is making all this carbohydrate, this sugar and it's showing up in the morning. So even if you take a diabetic who has severe insulin resistance, 80% of their blood sugar is coming from their liver making a lot of glucose and that may influence A1C and so it's a good idea sometimes to measure your blood sugars in the morning. I think what I would recommend if you have this is you want to get rid of the thing that created in the first place which is eating too many carbohydrates. If you start going on a low carb diet and you start reducing the need for this insulin, you are going to eventually correct this in relatively short period of time, several months. So, it's the combination of intermittent fasting and going low carb will ultimately correct this a problem with this, lower this, and also correct this right here. You just want to stick with it. Keep doing it until eventually you wake up in the morning, you check your blood sugar, and it's normal. Couple other things you could do. You can go for a long walk in the morning to walk off and burn off that sugar. Now, another thing that I know doctors really don't focus on nutrition, but if you were to do a blood test for your minerals, especially potassium or magnesium or even selenium or zinc, which are also important trace minerals, chances are they're going to show normal in the blood because these minerals are usually not hanging out in the blood. They're deep in the tissues. And so when you're checking the blood, you're only checking a very tiny percentage of where that mineral is. Maybe like 1 to 2%, maybe a little bit more with this. And so you're searching for deficiency of something in the wrong place. There are very specialized tests to pick up potassium, magnesium, selenium, and zinc. Instead of going through them in this video, I'm going to put them down in the description so you can get that data if you wanted to test minerals. But typical blood tests don't give you accurate information what's going on with the minerals. Like even magnesium for example, which is super important. If you check the blood and it's normal, you could actually be deficient because in your cells where the majority of magnesium is, it could be lowered but allow a little bit of it to trickle in the blood giving you the sense that you're normal but you're really not. Let's talk about number five, B12. When you check B12 in the blood, you're not just checking the active form of B12, but you're also checking part of the inactive B12. There's another test called MMA test that will pick this up better. And another good one to test this out indirectly would be to check a homocyine. I will include that down below as well. Number six, CRP C reactive protein. This is an inflammatory marker and so many people are inflamed. You want this number to be as close to zero as possible. You want it to be below one. I've talked to many doctors that will say, well, you know, if you're below three, you're fine. I disagree because that is a inflammatory process that's going on. And even though the average person has inflammation, that doesn't make it normal because again, the normal is basically average and I don't want to be average. I want to be healthy. If your CRP is between like 1.5 or two, like let's just say an average of 1.8, that's not good. Okay? You don't want that. That is a lowgrade inflammatory state. And a couple things you can do to improve this through diet of course. Avoid seed oils. Avoid sugar, refined carbohydrates, junk food. Focus on getting rid of your visceral fat. Make sure you sleep better. These are all things that will greatly improve this in addition to omega-3 fats, which is a natural anti-inflammatory. I like cod liver oil. And then now, let's get to number seven, cholesterol. I'm going to do a separate video on this, but cholesterol is something your body makes. It doesn't just equate to a disease. And just because you have high cholesterol does not mean it's a problem. Especially if you are on a low carb diet because people that are on a low carb diet, they eat more fat. They're mobilizing more fat. You're going to actually see more cholesterol in the body. And so one really important element of that is to look at the carrier of cholesterol because cholesterol is not just floating in your blood. It's in a little container that is delivered to the cells and then from the cells back to the liver. And LDL is the number one most confused part of this cholesterol story because there's actually two different types of LDL. And by the way, most people think LDL is bad cholesterol, but it's not. It's something your body makes to deliver cholesterol into the tissues. And so this is why it's really important to do a specialized lipid profile test instead of just a general cholesterol test because you want to be able to pick up the two different types of LDL. Pattern A and pattern B. Pattern A is the large buoyant LDL. This is the one that is usually associated with people on a low carb diet. This is usually the one that's non pathogenic because the size of these particles are big and they're floating and they're not invading the arteries creating inflammation. On the other hand, the pattern B LDL is a small dense particle size which can invade the arteries and is associated with more inflammation and more problem with heart disease and it's more pathogenic. So, you want to do this specialized test to pick up what you have more of. Is it this or that? The way that you get more of this is you go low carb. The way that you get more of this is you eat more carbohydrates. Number eight is cortisol. The problem with testing your cortisol is cortisol is on a wave. And if you just check your blood tests with cortisol at one time of the day, you're not going to pick up the whole picture. A better test would be a saliva cortisol where you're checking in the morning, noon, evening, and the middle of the night. So you can get a full picture of what's going on. But of course, it's a pain in the butt because you have to get up in the middle of the night. So there are other tests that you can do to pick up cortisol indirectly. And one of the best tests is uh heart rate variability test. Some people have the watches, some people have the bands around the waist, some people even have the rings. HRV technology has come a long way. That measures the autonomic nervous system through the heartbeat. And then lastly, I want to talk about vitamin D. When you test your vitamin D, you're testing the inactive vitamin D in your blood. You're not measuring what's going on in the active form inside your cells. Here's what a lot of even doctors don't know. A very high percentage of the population has what's called vitamin D resistance. their blood levels look normal, but they're actually very deficient. There's a couple other things you can test with vitamin D to kind of indirectly know if vitamin D is penetrating the cells or not. And the test that you want to do is called a parathyroid hormone test. So if you check your vitamin D levels and if it's normal and then your parathyroid is high, you can kind of indirectly deduce that I'm probably not getting enough vitamin D. So this parathyroid hormone is compensating. So you really want your parathyroid hormone to be normal and that way you know your vitamin D is kind of connecting into the tissues. And this 20 nanogs per milliliter for vitamin D is ridiculously too low. I would recommend at least 50 to 70. But if you're trying to therapeutically fix something, you want it even higher than that. I've done 284 videos on this topic. Now that you know this basic information, I highly recommend you watch my video on this LDL to get all the details to really fully understand this because this is where so many people are confused because there's all these big words. So, I created a video to make it very, very simple right here. Check it out.

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