Should You Care About Your HbA1c Levels?
HbA1c or glycated hemoglobin is a blood marker that most, if not all, type 2 diabetics will be very aware of.
But is this something that only concerns diabetics?
Or is it in everybody’s best interest to know what their levels are? Let’s dive in.
What is HbA1c?
To some, it’s hemoglobin A1c, to others it’s glycated hemoglobin and to the rest it’s simply just A1c. However you want to call it, this very simple blood biomarker has all to do with how much glucose (sugar) has been in your blood - which makes this an important screening process for diabetes.
Hemoglobin is the oxygen-carrying component of red blood cells which takes oxygen to the cells of the body to be used up as energy.
As glucose can become sticky when wet, it can bind onto and attach itself to various protein structures, hemoglobin being one of them. When this happens, we say that the structure has been ‘glycated’.
An important piece to understand with HbA1c is that as red blood cells have a typical shelf life of 3 months, your HbA1c levels are reflective of your blood glucose levels of the last 3 months. This gives us a slightly broader picture to analyse your gluocse levels and is currently the gold standard for diagnosing type 2 diabetes.
What should our HbA1c levels be?
In the right amounts, glycated hemoglobin is a normal process that shouldn’t be a cause for concern, however, when HbA1c levels rise it is a strong indicator that blood glucose levels are also rising which can be dangerous.
A HbA1c of 5.7% - 6.4% will put you in the prediabetes range and anything over 6.5% will tip you over to full type 2 diabetes.
Having said that, there does seem to be variances in HbA1c levels between different ethnicities.
For example, this meta-analysis found that black, Asian and Latino non-diabetics had a higher HbA1c than whites. The reasons for this are still unclear however this goes to show that an individual’s HbA1c could be genetically influenced and therefore a case-by-case assessment considering other biomarkers must be made when diagnosing diabetes (Cavagnolli et al, 2017)
How often should I check my HbA1c?
If you haven’t had yours checked in the last 5-10 years, it would be a good idea to get an updated test.
For individuals with no family history of diabetes or other cardiovascular health issues and are generally living a healthy lifestyle, a retest every few years would suffice.
However, for individuals at higher risk (overweight, obese, family history) keeping a closer eye on your levels is recommended. Especially if you are testing in the high 5% - low 6% range at the moment.
What does having a high HbA1c actually mean?
On a basic level, a high HbA1c tells us that there have been high numbers of glucose molecules floating around in the blood over the last 3 months.
Before we move on, we must appreciate just how tightly controlled our blood glucose levels are. At any given moment, throughout the whole of the human body, we have about 1tsp of sugar floating through all of our blood vessels. Just 1 tsp! (About 5grams).
When we compare that to the roughly 500g that the body can store (roughly 400g in our muscles and 100g in our liver), 5 grams pales in comparison. Hormones like insulin and glucagon work around the clock involuntarily to regulate this for us and therefore moments of high blood sugar (hyperglycemia) or low blood sugar (hypoglycemia) are quickly picked up by the body with symptoms ranging from mild to severe and even sometimes fatal.
Your glucose levels are constantly fluctuating throughout the day, with an increase in cortisol levels prior to you waking up establishing the first rise in glucose in the morning. A typical 24 hour span would see rises in glucose levels after activities like eating, stressful events or physical exercise which would then lower back down to a more stable level between these activities. HbA1c is a measure of the average of these ‘highs’ and ‘lows’.
What a high HbA1c tells us is that the body has been having a hard time lowering glucose levels. Insulin is the hormone that takes glucose molecules out of the blood to be deposited into muscle and liver cells for storage and when this mechanism breaks down or becomes faulty, this is known as insulin resistance. The hallmark feature of type 2 diabetes.
Why are high glucose levels dangerous?
As blood glucose levels rise. more and more glucose molecules bind onto protein structures which denatures them. This is what causes damage to the microvasculature of the body such as the blood vessels in the eyes, kidneys and extremeties which are usually the first to experience this (Chawla et al, 2016).
Can stress impact HbA1c levels?
One of the ways in which the body deals with stress is by increasing glucose levels. From a survival point of view, it is one of the many physiological responses that help us deal with a physical threat - say, getting away from a tiger for example. The issue is that in today’s world, our main stressors are non-physical i.e. work deadlines or being underslept, but the body deals with these stressors in the same way by releasing glucose in the blood.
In the example of being chased by a tiger, we would appropriately use up the glucose for energy, however the same can’t be said about our chronic, low-grade everyday stressors.
It’s hard to say whether non-physical daily stressors alone would be enough to send HbA1c levels to the levels seen in diabetes but what tends to happen is that stress is typically accompanied with unfavourable food choices. This is where the double whammy of stressful eating can really impact glucose levels and consequently HbA1c levels, especially if this causes weight gain (Boye et al, 2021).
Can HbA1c levels be lowered naturally?
In short, yes. The process of becoming insulin resistance occurs along a spectrum. On one end you have non-diabetic individuals who are insulin ‘sensitive’, and as you become more resistant to insulin, prediabetes ensues which is then followed by full blown diabetes.
Many of the processes taking shape that turn somebody insulin resistant are actually reversible through making lifestyle changes, improving body composition and eating a healthier diet.
Whether you need medication or not will come down to how severe your insulin resistance is and whether you need more immediate support because seeing improvements in blood glucose control and HbA1c through lifestyle modification does take time.
Other considerations for HbA1c levels
As insulin resistance occurs along a spectrum, it is vitally important to recognise the earlier stages of the disease as it’ll be easier to treat.
Chronically elevated glucose levels after eating (post-prandial hyperglycemia) is a good indicator that there is some insulin resistance brewing in the background and suggestive of prediabetes. And by high, I’m talking levels of between 8-11mmol/L consistently (Gerich, 2013).
You can check your own levels by doing a finger prick test 30-60 minutes after eating or by using a continuous glucose monitor.
Another thing to be aware of is that HbA1c levels could be influenced by things like iron deficiency anaemia or if the average lifespan of your red blood cells is longer than 3 months (Ghazanfari et al, 2010)
This is why to increase the accuracy of assessing insulin resistance and diabetes, combining fasting blood glucose levels with HbA1c is a good idea.
Summary
HbA1c is currently the gold standard for diagnosing type 2 diabetes as it shows your average blood glucose levels over 3 months. The cut-off is 6.5%.
As insulin resistance and type 2 diabetes occur along a spectrum, it would be smart to become aware of the earlier stages of the condition as an elevated HbA1c is usually indicative of the disease in a progressed state.
Post-prandial hyperglycemia is usually the first warning signs of insulin resistance/prediabetes and an at-home finger prick test can tell you your levels, as can a continuous glucose monitor.
Those at higher risk of this common metabolic disease such as individuals with a family history of diabetes, overweight/obese individuals, blacks, Hispanics and Asians should be more acutely aware of their HbA1c and more willing to do regular testing.
However, HbA1c isn’t perfect as there are genetic factors that can influence glucose levels, especially in ethnicities such as blacks, Hispanics and Asians. It can also provide a slightly misleading picture for those with iron deficiency anaemia and those with a longer red blood cell lifespan.
I hope you found this article informative and if you are looking for extra support with improving your blood glucose management, feel free to drop me a message about how my 1-2-1 coaching service can help.
References
Boye KS, Lage MJ, Shinde S, Thieu V, Bae JP. Trends in HbA1c and Body Mass Index Among Individuals with Type 2 Diabetes: Evidence from a US Database 2012-2019. Diabetes Ther. 2021 Jul;12(7):2077-2087. doi: 10.1007/s13300-021-01084-0. Epub 2021 Jun 2. PMID: 34076849; PMCID: PMC8266935.
Cavagnolli G, Pimentel AL, Freitas PA, Gross JL, Camargo JL. Effect of ethnicity on HbA1c levels in individuals without diabetes: Systematic review and meta-analysis. PLoS One. 2017 Feb 13;12(2):e0171315. doi: 10.1371/journal.pone.0171315. PMID: 28192447; PMCID: PMC5305058.
Chawla A, Chawla R, Jaggi S. Microvasular and macrovascular complications in diabetes mellitus: Distinct or continuum? Indian J Endocrinol Metab. 2016 Jul-Aug;20(4):546-51. doi: 10.4103/2230-8210.183480. PMID: 27366724; PMCID: PMC4911847.
Gerich J. Pathogenesis and management of postprandial hyperglycemia: role of incretin-based therapies. Int J Gen Med. 2013 Dec 4;6:877-95. doi: 10.2147/IJGM.S51665. PMID: 24403842; PMCID: PMC3884108.
Ghazanfari Z, Haghdoost AA, Alizadeh SM, Atapour J, Zolala F. A Comparison of HbA1c and Fasting Blood Sugar Tests in General Population. Int J Prev Med. 2010 Summer;1(3):187-94. PMID: 21566790; PMCID: PMC3075530.