Diagnosis: High Blood Sugar (A1C). Now what?

What is blood sugar and why are high levels a problem? Here’s what you need to know about A1C, fasting glucose and all things related to blood sugar.

What is blood sugar?

Blood sugar, otherwise known as blood glucose, is the body’s main source of energy. When we eat carbohydrates, the digestive process breaks them down into glucose to then release into the bloodstream for circulation to tissues around the body.

Blood sugar must remain within a certain range for optimal health: the hormone insulin, released by the pancreas (an organ), helps us manage blood sugar levels by shuttling glucose into cells where it can be used for energy. The more glucose there is in the bloodstream, the more insulin will be required.

You can think of insulin as chaperones produced by the pancreas that are released to assist the glucose into the cells. With insufficient chaperones available, glucose would just build up in the blood stream, eventually reaching an unhealthy level and wreaking havoc.

Why is blood sugar an important health metric?

When blood sugar is too high, the body falls into a state of hyperglycemia. Short term effects can be as mild as a headache, whereas chronically-elevated levels will lead to insulin-resistance and to the subsequent development of diseases like prediabetes and Type-2 diabetes.

Living with these diseases can be uncomfortable due to constant fatigue, frequent urination, and numbness in the extremities. Additionally, when blood sugar remains uncontrolled for too long, the elevated glucose in the bloodstream will eventually damage nerves and organs. This damage can lead to the development of blindness, the need for limb amputation, heart disease, and (eventually) premature death.

Did you know? You can suffer from high blood sugar, prediabetes and Type-2 diabetes without being overweight. 
Diet, physical activity levels, and stress all play a major role in the management of blood sugar levels, so while obesity can contribute to elevated blood glucose levels, people of every body weight can still be at risk of blood sugar-related diseases.

How is blood sugar measured?

To measure of the amount of sugar in the bloodstream, a blood sample is needed. This sample can be taken venously (by a clinic/lab) or can be achieved via finger prick for quick at-home readings. Wearing a continuous glucose monitor (CGM) is another option for tracking blood sugar readings accurately over an extended period of time. However, a CGM is costly and generally unnecessary for people who do not have diabetes.

What is considered an elevated blood sugar level?

Clinically, there are three main tests for used to assess blood sugar:

• Hemoglobin A1C (Hb A1c, often listed as just A1c)
• fasting blood glucose,
• and the oral glucose tolerance test.

Here in Canada we use mmol/L, but here is a handy conversion chart to mg/dL for those in the US.

A1c levels are used for the diagnosis of Type-2 diabetes, as they provide a measure of blood glucose over an 8-12 week span. In other words, someone’s A1c tells us how high their blood sugar has been over the last few months. A normal A1C level is under 6.0% while anything over that indicates a diagnosis of either prediabetes (6.0-6.4%) or diabetes (>6.5%).

Going back to our previous simplified chaperone analogy, A1c is an indication of how much blood sugar has hitched a ride to haemoglobin found in your red blood cells. The longer glucose hangs around in the blood without insulin helping chaperone it into cells, the more likely it is to hitch a ride with your red blood cells.

Fasting blood glucose is descriptive; it gives a reading of your fasted blood sugar levels on the day of your blood test (>12 hours without eating). This measure demonstrates where your blood sugar levels ‘rest’ without insulin in the bloodstream. A healthy result is <5.6 mmol/L and anything above that is indicative of either prediabetes (5.6-6.9 mmol/L) or diabetes (>7.0 mmol/L). If someone has a high reading for the first time, they’ll typically be counselled on lifestyle advice to help bring it down before being re-tested.

A glucose tolerance test is also descriptive; it reveals how blood sugar levels react to the ingestion of a high-sugar liquid. In this test, you’d be given an unpleasantly sugary drink to consume and then have blood draws at intervals up to three hours after the drink to determine how well your body responded to and processed the sugar. A healthy result is <7.8 mmol/L and levels above that are indicative of either prediabetes (7.8-11.0 mmol/L) or diabetes (>11.1 mmol/L).

Once again, going back to our analogy, this test indicates how well the insulin chaperones are released (remember, they come from the pancreas) to assist with clearing glucose from the blood stream after ingesting a lot of it.

Can blood sugar be too low?

Low blood sugar is called hypoglycemia. Type-1 diabetics are the group most at risk for hypoglycemia, followed by people with Type-2 diabetes who take insulin or other blood sugar-lowering medications. For people without diabetes, this condition can happen in extreme circumstances such as extended fasting or ketogenic diets, too much physical exertion, exposure to high temperatures/humidity, or other underlying conditions (such as kidney disease).

Causes of chronically-elevated blood sugar

While it is normal for blood sugar to rise after a meal, it is dangerous when levels don’t drop back down to a resting level within a few hours. There are multiple factors that can result in chronically high blood sugar levels which, in turn, lead to the development of prediabetes and Type-2 diabetes. The following are considered risk factors for developing chronically high blood sugar levels:

• Family history of insulin resistance/Type-2 diabetes
• Smoking
• Physical inactivity
• Chronic stress
• Excessive intake of processed foods (notably sugar/carbohydrates)
• Habitual alcohol intake
• Obesity
• High blood pressure/hypertension

It is vital to know your family history. The likelihood of developing Type-2 Diabetes is 3x greater if someone in your family has previously been diagnosed with it. Genetics are non-modifiable risk factors which ultimately means it becomes even more important to address the lifestyle factors that are within our daily control.

Outside of genetics, the common thread among the modifiable risk factors is that they are all highly inflammatory inputs to the human body. If you are exposed to one or more of these stimuli for an extended period of time, resting blood sugar levels will become increasingly elevated over time.

How to lower blood sugar levels

The most effective ways to manage blood sugar levels and lower A1c are as follows:

1. Increase physical activity

• This is the body’s innate “magic” ingredient because muscles that are put to use regularly with exercise are glucose sinks, taking up and using blood sugar. Going back to our earlier analogy, when muscle is worked, there are extra “doors” that appear for your insulin chaperones to assist glucose through. Having more doors helps clear a crowd!
• While frequent aerobic/cardiovascular training has always been the main recommendation for lowering blood sugar and still is, new research shows that any form of activity is effective at lowering blood sugar.
• The exercise dosage is what is most important, so if your blood sugar is high, choose any activity that you find the most enjoyable or that’s easiest to work into your daily routine. Start with whatever dosage you can manage, and build this up over time. The more consistently you’re able to do it, the better the effects.
• Aim to achieve the weekly minimum recommended dosages of >150 hours of moderate intensity activity and >2 sessions of resistance training.
• Something is better than nothing, and more over time is generally better.

2. Increased dietary fibre intake

• Dietary fibre slows digestion and helps to regulate spikes in blood sugar levels. Increasing daily intake of fruits and vegetables is the top way to introduce more fiber into the diet, although fibre supplementation can be a helpful tool as well.

3. Reduced consumption of alcohol

• Less than 2 standard drinks/day for men, and less than 1 standard drink/day for women.

4. Cessation of smoking

• The chemicals in cigarettes make insulin less effective, causing blood sugar levels to rise. People who smoke are 30 to 40 percent more likely to develop Type-2 diabetes; the more cigarettes you smoke, the higher your risk for Type-2 diabetes.

5. Increased intake of whole food sources

• While dietary fiber is king for blood sugar regulation, any dietary changes that reduce the overall intake of ultra-processed foods will be impactful. The aforementioned fruits and vegetables are priority 1, but it is also beneficial to increase intake of foods like nuts, seeds, fish, eggs, fresh meat, legumes & whole grains (to name a few).

6. Weight loss (if you are currently overweight)

• If you are overweight or obese, even a small amount of weight loss will have a favourable impact on blood sugar levels.
• As previously discussed, weight loss is complicated and effective maintenance of a lower body weight happens as a symptom of altered daily actions such as increased physical activity and healthy eating. This is in direct contrast to having a singular focus on weight loss, particularly through extreme measures.

A combination of the above strategies will always lead to the best results. If you find you’re not achieving aspects of the above list, focus on whichever one is the most attainable to you first. Once you feel you have a handle on one element, add in another layer and you’ll be well on your way to reducing your risk factors for Type-2 diabetes and beyond.

What about medications?

There are many available medications that help manage A1C and Type-2 diabetes. One of the most commonly prescribed medications is metformin, which decreases the amount of glucose being produced by the liver. It is a very effective drug for people who have diabetes and who are not exercising. Oddly enough, metformin has been shown to blunt the positive impacts of exercise, so it’s not a great option for anyone who is already physically active or those who want to reap the benefits of integrating physical activity into their management.

Lately, GLP-1 agonist drugs have been getting all the headlines (e.g Ozempic/Semaglutide) due to their propensity to help many people lose weight quickly. Note, this doesn’t work for all and weight loss isn’t a panacea on it’s own. These drugs mimic human hormones that stimulate insulin release while blocking those that cause blood sugar to rise. As with all prescription drugs there are side effects that may or may not be tolerable to the individual.

Physicians are uniquely qualified to help patients determine which drugs are right for them, whether as monotherapy or in combination, based on individualized circumstances.

By and large, medications are better when they can be combined with exercise; there is so much that exercise does for the body beyond blood sugar management that pharmacology simply cannot substitute.

Which is better, exercise or medications?

As mentioned above, metformin and exercise are not great partners. For individuals with Type-2 diabetes, metformin has shown to be more effective at reducing A1c, but for those who have not already been diagnosed with diabetes, exercise is the better option to manage glycemic control.

Regarding GLP-1 agonists, exercise is a vital adjunct to treatment. These drugs can cause rapid weight loss which includes muscle mass, the cornerstone of metabolic health. As such, it’s crucial to incorporate exercise in an effort to maintain muscle mass and cardiovascular health.

Long story short: Physical activity is the undisputed king when it comes to human health, and should be the recommended backbone for all disease management.

In Summary

• High A1c and chronically-elevated blood sugar levels will lead to insulin-resistance and to the subsequent development of diseases like prediabetes and Type-2 diabetes.
• You can suffer from high blood sugar, prediabetes and Type-2 diabetes without appearing to be overweight or obese.
• Chronically-elevated blood sugar levels are caused by behaviours such as smoking, physical inactivity, chronic stress & habitual alcohol intake.
• The likelihood of developing Type-2 Diabetes is 3x greater if someone in your family has previously been diagnosed with it. However, neither genetics nor age alone lead to an inevitable development of this or any other type of chronic disease.
• Both medications and exercise are effective at managing blood sugar levels; exercise provides additional health benefits on top of medication.
• The more lifestyle based strategies applied to reducing A1c levels (increasing exercise, reducing alcohol, replacing processed foods with whole foods, etc.), the more you can reduce your risk of diabetes.

Recommended Reading & Listening

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Resources

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