Diabetes Blood Sugar Basics

Is your head spinning trying to understand everything about diabetes blood sugars?

Sometimes it’s helpful to have a basic explanation. So here’s your 101 on diabetes blood sugar basics.

Diabetes Blood SugarI’ve complied answers to some of my clients’, friends’ and readers’ most common questions about diabetes blood sugar.

Q: What should my blood sugar level be?

A: There is no single number that is right for every person with diabetes. Your blood sugar targets should be individualized based on your health status, age, how long you’ve had diabetes, your medications, risk for low blood sugar (hypoglycemia) and other things. However, the American Diabetes Association (ADA) has these general targets.

  • Fasting & Before Meals: 80 – 130 mg/dl
  • 1 – 2 Hours After Eating: < 180 mg/dl

Talk to your healthcare provider to learn your specific blood sugar targets. It’s to important to know that these targets are general targets for people with diabetes. They are not numbers for people who do not have diabetes.

Q: Why does my doctor want my A1C level to be less than 7%, but my mom’s doctor told her that he was pleased with her A1C level at 7.8%? Shouldn’t my mom and I aim for the same A1C goal?

A: Not necessarily. The ADA general target for A1C is < 7%. But just like we personalize other blood sugar targets, A1C goals should also be specific to the individual. Lowering A1C to < 7% reduces the risk of microvascular complications of diabetes such as nerve, kidney and eye problems. And if people with diabetes achieve this level of blood sugar control early in the course of the disease, their risk of heart disease is also reduced.

But having tight blood sugar control also comes with risks. Some people with diabetes are more likely than others to have hypoglycemia, which might lead to falls or driving accidents, for example. (The risk of hypoglycemia largely depends on medications.) Plus, some studies suggest that stringent blood sugar control among people with established heart disease or among people who have had diabetes for a very long time might be harmful. For this reason, the ADA suggests that A1C goals be individualized based on health status and other concerns. Some people will benefit from an A1C goal of < 6.5%, but others will need a more lenient goal of say 8%.

Q: Wouldn’t I know by how I feel if my blood sugar level is high?

A: While it’s not unsual to feel fatigue from poorly controlled blood sugar levels, going on a feeling is very unreliable. And making treatment decisions based on feelings instead of actual blood sugar numbers can be dangerous.

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Q: What are some things that make my blood sugar level go too high?

A: Carbohydrates will raise your blood sugar more than any other nutrient. The foods with the most carbohydrates are these:

  • Starches including grains, starchy vegetables like potatoes and corn, and pulses like black beans, kidney beans and lentils
  • Fruits including fresh, frozen, canned, dried and fruit juices
  • Milk and yogurt, including milk substitutes like soy milk
  • Sweets and treats including sugary beverages, sports drinks, snack bars, honey, agave nectar and jelly

Other things that might cause your blood sugar levels to go too high are these:

  • Not taking your diabetes medications properly
  • Taking medications that can cause hyperglycemia
  • Infection, illness or injury
  • Menstrual cycle

Q: What are some things that make my blood sugar level go too low?

A: Hypoglycemia (low blood sugar) occurs when your blood sugar falls below 70 mg/dl. If you do not take insulin or another medication that has the side effect of hypoglycemia, you likely have a very low risk of having your blood sugar level drop too low. It’s a myth that most people with diabetes are at risk for hypoglycemia. Thus it’s a myth that most people with diabetes need to snack or eat often.

Many things can cause hypoglycemia, including these:

  • Skipping a planned meal or snack or eating too little carbohydrate (if your medication has the side effect of hypoglycemia)
  • Exercising more than usual (especially if your medication has the side effect of hypoglycemia)
  • Drinking alcohol, especially if you do not eat carbohydrate-containing foods at the same time
  • Taking too much diabetes medications

The ADA identifies the signs and symptoms of hypoglycemia and explains how to treat it. Hint, it’s NOT the right time to treat yourself to that jumbo chocolate bar.

Q: Since carbohydrates turn into blood sugar, shouldn’t I just stop eating them?

A: I agree that this seems logical, but avoiding carbohydrates is quite problematic. I write about the benefits of carb-rich foods in an earlier post. It’s critical to consider that controlling blood sugar is only one part of diabetes management. In type 2 diabetes, insulin resistance is a major problem. Though insulin is best known for its role in blood sugar control, insulin actually has quite a number of jobs and affects both protein and fat metabolism too. Insulin resistance affects blood pressure, triglyceride levels, liver health, cardiovascular health and so much more. While avoiding carbohydrates will lower blood sugar levels, it’s not a cure for insulin resistance.

People with diabetes have double to quadruple the risk of developing heart disease. They also have a higher-than-average risk of developing certain types of cancer. Carbohydrate-rich foods like fruits, vegetables, whole grains, and beans and lentils are loaded with disease-fighters, including heart disease fighters and cancer fighters. Plus, if you avoid foods with carbohydrates, then you’ll likely be eating an excess of other foods. Instead of avoiding carbohydrates, count them. Learn the basics of carb counting and how to count carbs like a pro.

Q: Why is my blood sugar higher in the morning than it is when I go to bed? I am definitely not eating in the middle of the night!

A: This one confuses a lot of people! During the night and when you are fasting, your liver provides sugar to the blood. This is normal and is necessary to keep the body functioning during periods without food intake. Unfortunately, there is often some miscommunication in type 2 diabetes. Because of insulin resistance, the liver does not recognize that blood sugar levels are high enough and it continues to send out excess sugar, making high levels of blood sugar even higher. Surprisingly, including some carbohydrate-containing foods like a piece of fruit in your breakfast can shift you out of the fasting state and improve blood sugar levels.

What more would you like to know about diabetes blood sugar levels? I’ll answer your questions in future posts?

In the meantime, stay on track. Grab your free 1-year schedule of diabetes appointments and tests to keep you in your best health.

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Jill Weisenberger

I'm Jill, and I believe simple changes in your mindset and health habits can bring life-changing rewards. And I don't believe in willpower. It's waaaay overrated. As a food-loving registered dietitian nutritionist, certified diabetes care and education specialist and certified health and wellness coach, I've helped thousands of people solve their food and nutrition problems. If you're looking for a better way to master this whole healthy eating/healthy living thing or if you're trying to prevent or manage diabetes or heart problems, you'll find plenty of resources right here.

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  1. Debra on January 26, 2019 at 10:06 am

    I am learning quite a bit from your blog that I haven’t learned from my diabetic nutritionist. However, I am confused about including grains in a meal plan for diabetics, such as organic rolled oats or steel cut oats, when these foods raise blood sugar. Adding these types of foods seems contraindicated.

    • Jill Weisenberger on January 27, 2019 at 12:20 pm

      Your question is not uncommon, so thank you for asking it. Often people think that because grains, fruit, legumes, etc raise blood sugar that people with diabetes should avoid them. I understand why some people think this, but I firmly disagree. First of all, these foods raise blood sugar in all of us, not just people with diabetes. But most importantly, these are health-boosting foods. People with diabetes must be carb-aware, but not carb-phobic or carb-avoiding. They key is to find the balance in your diet (and other lifestyle habits, as well as meds) that allows for blood sugar management, enjoyment and includes all types of disease-fighting foods. Grains are important for many reasons, including their fiber. Fiber is strongly linked to better heart health, and it’s the grain fiber that appears to be the most important. Our gut bacteria thrive on having a variety of fiber types, so a varied diet is critical. Another very important thing is that wholesome plant foods like nuts, grains, fruit, vegetables, tea, and legumes provide so much more than carbohydrates. They give us thousands of phytonutrients that work together in the body with other nutrients and phytonutrients and interact with gut bacteria to improve insulin use, protect the eyes and the brain, lower cholesterol, turn off cancer, act as antioxidants, acts as anti-inflammatory compounds and more. There are so many of these phytonutrients that eating a varied diet is absolutely critical. I go into a bit of detail in my post about carbs. The bottom line is that the most healthful diet is the least restrictive – not the most restrictive as the current diet chatter might have us all believe. Does this answer your question clearly?

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Jill Weisenberger

I believe simple changes in health habits can bring you life-changing rewards.

And I believe willpower is way overrated.

Right here is where you can discover the mindset and habits to stick with healthy lifestyle choices most of the time - and drop the guilt when you don't.

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