Diabetes Basics

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Diabetes Basics

If you have been diagnosed with diabetes, then you know that controlling blood glucose is a critical part of your treatment plan. Good control requires a balance between:

Although not a medical device, the MyNetDiary Diabetes Tracker is a powerful tool that can help you understand your diabetes better. Please see our companion article, Tracking Diabetes with MyNetDiary for specific information about this incredibly useful application that is available for web, Android, and iPhone.

Carbs, Blood Glucose, and Diabetes

Carbohydrates ("carbs") are found in abundance in grains, grain products (e.g. bread), dried beans and peas (legumes), starchy vegetables (e.g. potatoes), fruit, juice, milk, yogurt, sugars, syrups, and sweets. The carbs that you eat and drink directly affect your blood glucose level. All digestible carbs are eventually converted to glucose, a simple sugar. Glucose travels through the bloodstream to provide cells with energy. Insulin, a hormone produced in the pancreas, is necessary to allow glucose to enter most types of cells in your body. Diabetes is a condition where there is not enough insulin, no insulin, or the insulin is not handled properly in the body so that levels of glucose in the blood rise and stay too high. When blood glucose is high enough, glucose leaks into the urine. Over time, high blood glucose can cause damage to our eyes, kidneys, nerves, gums, and vascular system (e.g. heart and brain vessels).

There are two major types of diabetes: type 1 and type 2 diabetes. In addition, there are two conditions that cause elevated blood glucose and increase the risk for type 2 diabetes: prediabetes and gestational diabetes. What is common to all types is that blood glucose is too high for health - it increases the person's risk for poor health and complications. In the case of gestational diabetes, high blood glucose increases risk to the fetus.

With diabetes, it is critical that diet, exercise, and medication work in concert so that blood glucose neither rises too high nor drops too low. Tracking helps us identify relationships between food and beverage intake, exercise, medication, body weight, and blood glucose. Once these relationships are understood, you can analyze, plan, and implement behavioral changes to better control your blood glucose levels, and therefore, diabetes.

The information contained in this article is mostly appropriate for type 2 diabetes and prediabetes, but has relevance to type 1 diabetes and gestational diabetes too. If you have been diagnosed with diabetes, then I urge you to get diabetes self-management education and training. This is typically offered in a clinic for people newly diagnosed with diabetes. Ask your doctor about getting a referral so that you get access to individualized care, goals, meal plans, self-management education, and appropriate follow-up.

Tracking Carbohydrates

Since I work as a diabetes educator, I hear patients describe all sorts of dietary strategies to control their blood glucose. Some just avoid sugary foods while others have completely eliminated all "white foods" from their diet. Your dietary strategy for effective blood glucose control will depend partly on your diagnosis, type of diabetes medication (if any), and whether or not you exercise.

Whatever strategy you choose, it is important that you know how to count carbs. The most common mistake I see is that folks only count sugar grams. This is a huge error since it severely underestimates one's carb intake and effect on blood glucose.

Total Carbs. The most common method of carb counting is to count total carb grams listed on the Nutrition Facts panel. This is the method of carb counting most often taught in diabetes education classes, especially for people newly diagnosed with diabetes.

Net Carbs. This value comes from subtracting all fiber and sugar alcohol grams from total carb grams. This method is no longer taught in diabetes education classes since it underestimates the total digestible carb load (and therefore, the expected rise in blood glucose after eating). Some amount of soluble or viscous fibers, although not digested in the small intestine, can be broken down in the large intestine, absorbed, and then converted to glucose. Also, some amount of sugar alcohols (low caloric sweetener) can be broken down and converted to glucose. This form of carb counting is fine for low carb diets but if you take rapid-acting insulin and find that your post-meal blood glucose is too high, then you might want to get help with adjusting your insulin to carb ratio or choose a different carb counting method.

Diabetes Carb Count. For those of you who use an insulin to carb ratio to dose your rapid-acting insulin, you might have been taught advanced carb counting. MyNetDiary Diabetes Tracker includes this method of carb counting as "Diabetes Carb Count":

Total Carbs - 1/2 (fiber if >= 5 grams/serving) - 1/2 (sugar alcohols if >= 5 grams/serving)

Please talk with your diabetes educator about the type of carb counting to follow or if you need help transitioning from one method to another.

How Many Carbs Can I Eat?

Your carb goal per meal and snack depends upon your blood glucose response to the foods you eat, your diagnosis, your diabetes medication, and your level of physical activity. If you have personalized carbohydrate goals for meals and snacks that is working well for you, then stick with it. But if you want general guidelines, you can try starting with 30-45 grams total carbs per meal if you are a woman, or 45-60 grams total carbs per meal if you are a man. Most folks do well with a snack limited to 15 grams total carbs, but some active people might need 15-30 grams total carbs per snack.

If you have gestational diabetes, please follow the nutrition guidelines that your healthcare provider has recommended so that your blood glucose stays within a safe level to support and sustain the pregnancy.

If you take medication that increases insulin production, or if you inject insulin, then your risk of hypoglycemia (low blood glucose) is greater if you consume too few carbohydrates. Hypoglycemia can be life threatening - if your blood glucose goes too low you can pass out. Imagine if that happens while you are driving, working on a roof, or operating dangerous machinery! As well, skipping meals, having too large of a gap between meals (e.g. more than 4-5 hours between meals), and engaging in more exercise than typical can increase your risk for hypoglycemia.

How do you know if your carb goal for meals is appropriate? You won't unless you check your blood glucose. And that is another good reason to seek care from your healthcare provider or diabetes educator - to learn how and when to monitor blood glucose. Your blood glucose testing schedule should be guided by a diabetes care professional. If your A1C continues to remain high (e.g. > 7%), then ask your doctor for a referral to diabetes self-management education and training so you can learn how to better manage your blood glucose with diet, exercise, and medication.

What Type of Carbs Can I Eat?

Although the carbohydrate content of your meal or snack will most directly affect your blood glucose level, the type of carb you consume also plays an important role. As a general rule of thumb, when comparing foods/drinks of similar total carb content, the one that is higher in fiber and lower in sugar is typically the better choice to control post-meal blood glucose. However, just because a food contains sugar does not mean it is forbidden or off the menu. For instance, a small piece of fresh fruit (or 1 cup of berries) is heart-, weight-, and diabetes-friendly and makes a perfect snack when combined with a small serving of protein such as cheese, nuts, or seeds.

Glycemic Index (GI) is the term used for how a single food affects blood glucose levels compared to a glucose solution (or white bread) with the same amount of digestible carbs. See The University of Sydney's About Glycemic Index for a detailed description of the GI and its use. The concept is simple - lower GI foods will cause a lower rise of blood glucose over a 2-hour period compared to foods with higher GI values. Therefore, choose more foods with a lower GI (less than 55) than foods with a higher GI (greater than 70). What is not so simple is how to actually use the GI in meal planning for diabetes. Here are some limitations with using GI for food selection:

Tip: If you like GI as a tool to help you make food choices, and then use it with common sense. Do not simply choose foods based on GI alone. Remember to look at the big picture - what else does that food provide and is it also weight- and heart-friendly?

Sugars, Syrups, and Honey

Do you have to cut out all sugars, syrups, and honey from your diet if you have diabetes? Not necessarily, but you do have to account for the carbs. Some foods are so high in carbs for commonly consumed portion sizes that I recommend that people either severely restrict their portion size or avoid them altogether. For example, 1 tablespoon of maple syrup contains about 52 calories and 13 grams carbs (all sugars) whereas 1 teaspoon contains only 17 calories and just over 4 grams carbs. So, if you use natural sweeteners, measure your portion size carefully and learn to like a less sweet taste.

Should you avoid all foods with high fructose corn syrup (HFCS)? Well, it depends. If the food contains small amounts of HFCS yet has nutritional benefit, then I would eat it. However, many sweetened sodas, teas, and energy drinks have a high HFCS content and just based on their total carb content alone makes them a poor choice for anyone, whether or not they have diabetes. Same goes for many packaged sweets. How many total carbs are you getting for a typical portion size? The danger is using your meal and snack carbs on junk foods that provide little or no nutritional value and that are likely to spike your post-meal blood glucose level sky high.

Artificial Sweeteners

If consumed in the same portion size, organic or natural sweeteners will raise your blood glucose level just as much as high fructose corn syrup and other highly processed sweeteners. All sugars and syrups are extraordinarily high in carbs - always measure these items carefully if you consume them.

Non-Caloric Sweeteners

Many people want to know if it is okay to use non-caloric (non-nutritive) sweeteners to cut down on carbs. If you consume the same portion size, then yes, a sugar-free version would lower your carb grams. For example, replacing a regular can of soda (39 grams carbs) with diet soda (0 grams carbs) significantly reduces both your calories and carb intake. But keep in mind that sugar-free does not necessarily mean carb free for all products. Always read the food label (Nutrition Facts panel) to check the total carb grams per serving, and measure your serving.

There is research that shows an association between regular high intake of non-caloric sweeteners and insulin resistance. For instance, Huang et al. published a study from the Women's Health Initiative in 2017 that found women who drank 2 cans of diet soda or more a day had an increased risk of diabetes compared to those who drank it rarely or never (< 3 cans/month). But women who drank diet soda still had half the risk of developing diabetes compared to women who drank the same amount of regular soda. Although diet soda drinkers had a lower risk of diabetes compared to regular soda drinkers, their risk was still higher than women who rarely drank it. Romo-Romo et al. in 2016 state that research needs to account for existing obesity and other factors before a definitive conclusion can be made about how non-nutritive sweeteners affect risk for metabolic diseases. As far as I can tell, neither study was funded by the sweetener industry.

If you drink soda daily and do not wish to stop, then at least transition to diet soda - that will have an immediate effect on your blood glucose. If you are sensitive to caffeine, consider a diet soda that is also caffeine-free. But ideally, consume less soda. If you crave something with flavor and caffeine, try unsweetened tea or coffee (but choose decaf if you are sensitive to caffeine). If you need it sweeter, try adding just 1 teaspoon of honey for 20 calories and 5 grams carbs. And don't forget - water is the best way to hydrate so be sure to drink that as a first choice.

Non-caloric sweeteners do not appear to cause cancer. You can learn more by reading Artificial Sweeteners and Cancer at the National Cancer Institute.

Specific Diet for Diabetes?

There is not one specific diet that all people with diabetes must follow. However, people with diabetes have a much higher risk for having a heart attack or stroke so heart healthy eating is critical. Eating more non-starchy vegetables is common to all healthier eating plans. As well, having carb goals for meals and snacks is important so that in concert with your exercise and medication use, you can keep your blood glucose within a safe range.

Mediterranean style. This type of eating plan is considered heart healthy given the high intake of vegetables, nuts, fish, and extra virgin olive oil. There is a fair amount of research to support this style as a wise choice for people with diabetes as well as to lower one's risk of developing diabetes. However, it is still important to be aware of carb intake and follow goals - you can still get too much of a good thing!

The Idaho Plate Method is a simple meal planner that limits carb intake to about 45 grams (3 carb choices) per meal. The concept is simple - half of your plate is filled with non-starchy veggies, 1/4 is filled with a protein food, and 1/4 is filled with a starch (ideally whole food/high fiber). In addition, add 1 cup of milk, yogurt, or non-dairy replacement and 1 small piece of fruit. You can learn more about this method by reading this short blog post at MyNetDiary: Simple & Healthful Meal Planner - Plate Method.

Low Carb. If you are an otherwise healthy person who is not yet taking medication for your diabetes or perhaps you are only taking metformin, then a low carb diet with heart healthy choices could help you kick start weight loss and control your blood glucose. If this is an eating style that appeals to you, talk with your healthcare provider and see what type would be best for you, given your medical history or other medical conditions.

It is a misconception that all people with diabetes have to eat low carb. However, it is wise for people with diabetes to have carb goals for meals and snacks so that their blood glucose does not rise too high after eating. If you take insulin or a sulfonylurea, then meals and snacks should be planned carefully to include enough carbs to avoid hypoglycemia. Another thing to keep in mind is that if you exercise, you can generally handle a higher carb load than if you are sedentary.

Important Diet and Lifestyle Factors

Let MyNetDiary Help You!

MyNetDiary can help you with tracking of foods and carbs, blood glucose, insulin, and more, making mundane tracking fast and easy. Diabetes Tracker is available online for MyNetDiary Premium members and separately as a standalone application for iPhone or Android phones. Benefits include:

You can take the reins and control your diabetes - it is within your grasp! If you have questions or comments about your tracking experience, please feel free to comment in MyNetDiary's Community Forum or Facebook page. I would love to hear from you!

More Resources

Last Updated on May 15, 2018

May 15, 2018
Katherine Isacks
Katherine Isacks, MPS, RDN, CDE - Registered Dietitian and Certified Diabetes Educator (CDE)

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