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clear search termsBlood Sugar: Surprising #1 Key Concept your At-Risk Clients Need to Know
Did you catch the first video in this series?
Most physicians still rely on fasting glucose to indicate when a patient has a problem with blood sugar management that needs more investigation. Most often chronically elevated blood sugar is caused by insulin resistance. Unfortunately, fasting glucose elevated outside the typical reference range happens after insulin resistance has been entrenched for some time. Check out this video to learn more about why fasting insulin (or even better, c-peptide) is perhaps The most important labwork marker for helping your client to identify when the early stages of insulin resistance have already taken hold. The earlier our clients identify this dynamic, the easier it is to reverse the inflammatory cascade and prevent diabetes from occurring – much less, it’s common partner: cardiovascular disease.
Fasting glucose is only a one-time marker that can be easily affected by short-term events (e.g. a particularly stressful commute to the blood draw). It is also highly influenced by cortisol awakening response – which can hide or amplify the real status of ongoing fasting glucose throughout a 24-hour period. Though the typical reference range for fasting glucose is 80-100 mg/dl, optimal is 90 or less (the lower half of the reference range). Individuals eating a particularly low carbohydrate diet may healthily have levels appreciably below the entire reference range.
So what about HbAc1? Great question. HbA1c measures the impact of blood sugar on hemoglobin, the oxygen carrying component of red blood cells (RBCs). Because RBCs live in the body 3-4 months, HbA1c is a much more useful marker to indicate the typical, ongoing blood sugar level. However, Hba1C has the same limitations as fasting glucose in that an elevated level is showing the downstream impact of insulin resistance that has been going on for some time. This marker also becomes less reliable for an individual who has some level of anemia due to suboptimal iron. Ideal HbA1c is typically 5.0% or less. Levels above 5.3% usually indicate some level of insulin resistance. Levels 5.7% and higher and usually diagnostic for physicians of pre-diabetes.
We have an opportunity as practitioners to help our clients to identify evidence of insulin resistance early on – BEFORE it has had the opportunity to cause elevated blood sugar. The video explains these dynamics in a way that you can easily relate to your clients.
Ideal fasting insulin is typically 4-7 mIU/L. Levels above this indicate insulin resistance. Levels much below this can indicate advanced pancreatic dysfunction, such as is seen in pancreatitis or unmanaged Type 2 Diabetes where pancreatic output has been stressed to the point where the gland simply cannot function at a minimal level.
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15 Questions for “Blood Sugar: Surprising #1 Key Concept your At-Risk Clients Need to Know”
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7.1
Nathalie says:
A similar answer was posted. Any condition that may affect the life span of RBC will cause variation of the HbA1c and can lead to false results. You may find it here: https://schoolafm.com/modules/puzzle-piecing-cases-core-101/#comment-23323.
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7.2
When there is iron deficiency anemia, there is a lower level of hemoglobin overall, so a certain amount of glycosylation will register as an abnormally higher percentage of the total.
Also, the current interpretation of HbA1c values measures hemoglobin glycosylation from exposure to glucose over a calculated average of 120-day lifespan of a red blood cell (RBC), assuming that the RBC life span is the same for all people. However, any conditions that reduce the rate of RBC renewal (e.g. anemia), even modest variations in production, and/or increase RBC average life span, may result in inaccurate falsely elevated HbA1c readings that do not correspond to actual plasma glucose concentrations (longer exposure to glucose).The opposite, a shorter RBC life span, could yield lower levels of HbA1c. You may be interesting in further reading:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5094338/
https://kresserinstitute.com/hemoglobin-a1c-not-reliable-marker/
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Carolyne Shapiro says:
May I ask if Homocysteine comes into play here at all? Total newbie here so pls excuse but just wondering — many thank yous!!!!
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6.1
We welcome all newbies, Carolyne, and we appreciate your courage to ask a question!
Homocysteine may come into play when the dynamic of high blood sugar and suboptimal methylation cycle has been in place long enough.
You may appreciate this post as well to learn more about methylation and homocysteine:
https://schoolafm.com/ws_clinical_know/homocysteine-an-often-hidden-heart-disease-risk-factor/
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stefanie Aring says:
At what level do iron and/or B12 deficiencies affect A1C levels? I have a patient who is overall very healthy, but has a ferritin of 24 and A1C of 5.3%. Fasting BS is 80. I suspect she has low stomach acid as her Ferritin is low and her B12 is only 327 as well, but she is not anemic. Can both the Ferritin and B12 levels being low cause her A1C to be slightly elevated? And what are the “cut-offs” for when B12 and Ferritin levels do not affect A1C levels?
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5.1
Alas, there are no ferritin or vit B12 ‘cut-offs’ that were defined for the reliability of the HbA1C. If anything I’d look at the hemoglobin level on the CBC – if that marker is on the low side, it may falsely indicate insulin resistance because of the general skewing of blood glucose to hemoglobin ratio. This is a good post for further reading on this issue: https://chriskresser.com/why-hemoglobin-a1c-is-not-a-reliable-marker/
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Sandy Anderson says:
My client was pre-diabetic for over ten years with an a1c of 5.7 and fasting glucose fluctuating between 100-119 and fasting insulin of 7 or 8. She is lean and athletic with good muscle tone. At the beginning of the year she removed all grains and processed carbs, eating lower carb with mostly vegetables (non-starchy) and some fruit (primarily low glycemic) with moderate protein and high healthy fat intake. She began intermittent (overnight) fasting daily 4-5 months ago with 14-16 hours between meals. Recent bloodwork shows a fasting glucose of 97, a1c of 5.0 and fasting insulin is less than 2. Is this low fasting insulin level and higher fasting glucose level any concern or a natural result of the lower carb diet and long 16 hour fasting period before the blood test? (She said she also took a two mile walk before the blood test.)
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SAFM Team says:
Well, first of all, the intention is to take a blood sample first thing in the morning without any substantial activity and with 10-12 hours of fasting. So the two-mile walk will definitely skew the results, especially the fasting glucose and fasting insulin, and a longer fasting window may have an effect as well. Especially in an extended fasting state, the body will release stress hormones in order to raise blood sugar to adequate levels if the exercise is aggressive enough to outpace the availability of fuel from ketosis. The most reliable marker given that is the HbA1c which does indeed show dramatic improvement – a great result. Remember that glucose is not just affected by diet; it’s affected by stress hormones e.g. cortisol, epinephrine. However, while most people experience a lower fasting glucose, it’s not uncommon for some following a ketogenic diet to have a more elevated fasting glucose, and generally if it’s paired with a low fasting insulin, is likely simply evidence that the body is sparing glucose for targeted use. Again, the HbA1c is the more important marker to assess ongoing, aggregate improvement.
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If the client’s blood sugar and a1c has been creeping up for the last 6 yrs – blood sugar now at 121 and a1c at 6.4 can we assume that the person is already pre-diabetic and don’t need the insulin challenge test?
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3.1
Yes. But keep in mind that the most important thing we can do is educate, empower and inspire a client to address the root cause. I don’t believe in using diagnostic language – primarily because it typically incites nothing useful at all…..usually a lot of fear and lots of googling and grouping themselves into alarming statistics and prognoses. Instead, teach them about the nuts and bolts of insulin resistance and how there is clear evidence that it’s been going on for quite a while and yet it can be reversed. Then show them how!
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Julie Oppenheimer says:
Can the fasting insulin be too low? Optimal range says 4 – 13 and the result was less than 2. Comment said intermediate risk.
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2.1
Yes. In fact, that is what happens in Type 2 diabetes when the pancreas has been trying to support a need for elevated insulin for so long that the gland is eventually unable to respond (“worn out”) and requires supplemental insulin. In this case, you will specifically see elevated blood sugar (and likely urinary ketones as well). However, a healthy person might consume a low carbohydrate diet that simply requires very little insulin, and the low level you state will be accompanied with healthy blood sugar, perhaps a bit on the lower end (e.g. 65-80 mg/dl) as the body has adapted to use ketones for fuel. In this case, it is likely just an adaptive response to the diet and not necessarily an issue at all. So we always want to look at the unique person who has a certain value vs. the value on its own. I also will say that given my research optimal for most people is more like 4-6. There are studies indicating that those with fasting insulin as low as 8 are more likely to develop type 2 diabetes.
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Laura says:
I had an insulin resistance test but they did Fasting, 1 hour and 2 hour readings. What are the ideal ranges at 1 hour and 2 hour please?
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Given all I have researched, I believe fasting insulin should be 4-5 IU/dl and both the one and two hour levels still less than 30. Optimal fasting blood sugar should be less than 90 mg/dl, and the one and two hour measurements should still ideally be less than 125 or so.
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Can you clarify the relationship between elevated HbA1C and anemia (low serum Hb)? To what degree does anemia have to be present for HbA1C to be an unreliable marker? What is the mechanism by which low Hb falsely elevates glycosylated hemoglobin?