No More Carb Confusion
Choosing your carbs wisely, not low-carb dieting, will help you control your glucose levels and your weight
What is low-carb dieting and what can it do for you when you’re trying to control your glucose and your weight? It’s true that carbohydrate-rich foods have the most immediate impact on your blood glucose control. But you’ll find that controlling your portions of all types of food, including those dense in carbohydrate, best helps you to manage your diabetes.
In the diet world, “low-carb dieting” is not the same as limiting carbs to manage blood glucose. Christine McKinney, M.S., a diabetes educator at The Johns Hopkins Bayview Medical Center, sorts through the carb confusion to highlight what you need to know about carbs and your diabetes.
Carbs and blood glucose
The quantity (measured in grams on nutrition labels and in many recipes) and source of carbohydrate from the foods we eat influence how much and how quickly glucose levels rise after a meal. Insulin (your body’s, if you don’t have diabetes or manage your Type 2 diabetes with medication; or injected insulin if you use insulin) is needed to convert the glucose into usable energy. Knowing and sensibly limiting your carbohydrate intake is an easy way to plan meals and keep your blood glucose levels on target.
Don’t confuse carbohydrate counting with low-carb diets like Atkins™ or South Beach™. These diets start with very few carbs for a few days, add more after an initial weight loss but remain low in carbs. For people with diabetes, counting carbs is a lifetime strategy for glucose control, not a short-term strategy for weight loss. Counting carbs is an everyday task, because the amount of carbs you consume each time you eat affects your glucose level over the next few hours.
Whether or not you have diabetes, your body needs to get about half its total calories as carbohydrate. The challenge with diabetes is knowing how much to eat at any one time to maintain good glucose control.
How many grams of carbs do you need?
The American Diabetes Association (ADA) recommends that 45-65 percent of total calories come from carbohydrate and that people with diabetes not restrict their daily total to less than 130 grams (about eight 15-gram servings) of carbohydrate. Keeping within the ADA recommended range, 50 percent of a 2,000-calorie diet is 1,000 calories. Foods with carbohydrate provide energy, fiber, vitamins and minerals. The glucose from carbohydrate is vital to your brain and central nervous system.
When you begin carb-counting, a nutritionist or diabetes educator can help you determine how many carbohydrate grams you need. Most people find the plan easy to learn and modify as needed. In the Diabetes Control and Complications Trial, a major 10-year study of people with Type 1 diabetes, people who followed a carbohydrate-counting meal plan kept blood glucose levels close to normal and had more flexibility with food choices.
Know your carbs
Wondering which foods contain carbohydrates? They can be broken down into the following categories:
- Sweets (including candy, cakes and sugary beverages)
- Starches (including breads, pasta, rice, crackers, cereal and starchy vegetables such as potatoes, peas, corn and legumes)
- Fruit and fruit juices
- Milk and yogurt
One serving of carbohydrate equals approximately 15 grams. This is NOT the same as the “serving size” listed on every nutrition label, which contains the number of carb grams also listed on the label. If a package of oatmeal, for example, says one serving contains 30 grams of carbohydrate, then eating that much oatmeal counts as 2 servings of carbohydrate toward a carb counter’s daily total. A serving may be as large as ½ cup or as small as 1 ounce, depending on the carbohydrate density of the food item in question. Examples of a single serving are a small banana, one slice of bread and a half-cup of mashed potatoes.
Many people like carbohydrate counting because it allows them to eat their favorite foods once they know the carb value. Carb counting lets you know how many carbs at a meal will lead to an after-meal blood glucose level that’s within your range. As a beginning carb counter, you figure that out by testing two hours after your meal. If your blood glucose then is within range or less than 50 points higher than your pre-meal reading, then the amount of carb you ate worked!
Let’s say you discover after a couple of weeks of carb-counting and post-meal blood glucose testing that 45 grams of carbs works for you at meals. This means you’ll have three servings of carbs (at 15 grams apiece) per meal. Now you have some choices to make. Maybe you’d like two starches and a fruit (two slices of bread and a small orange) for lunch. Or you want a fruit, milk and a starch. The choice is yours. All you need to do is make sure your servings or units of measure are accurate. (Is that ½ cup or 1 cup of pasta? If your portion size doubles, so will the carb content.)
You don’t need to carry all this carb information around in your head. Start by learning a few carb counts for your favorite foods. You can write them down or use flash cards, pocket-sized carb guides (sold at some grocery store checkouts), online guides or other tools to help you remember.
“Good” carb, “bad” carb?
Use common sense to choose healthy carbs. An apple is better for you than a chocolate chip cookie, even if they contain equal amounts of carbohydrate. Foods such as breads, cereals, pasta, fruits and milk are always better choices than cookies, candies and pies. It’s OK to have an occasional treat, but remember the carbs in it count toward your total for the meal and the day.
Use nutrition labels to calculate carbs
When eating prepared foods or using prepared ingredients, read the label to know what you are eating. The amount, in grams, of total carbohydrate per serving is listed in bold. “Total Carbohydrate” (not just the sugar grams) is the amount of carbs per serving in the food. You need to decide how much you’ll eat. If the serving size is ¾ cup but you are going to eat 1½ cups, you must double the total carbs per serving to know the amount of carbs you will be eating.
When you’ll be eating out, plan ahead. Many chain restaurants have nutrition information for their menu items available online or at the restaurant. And before long you’ll know, for example, that French fries have many more carbs per serving than cole slaw, making it easy to order a meal within your carb budget.
Beware of low-carb marketing
Marketing terms such as “low-carb,” “carb-wise” or “carb-fit” have not been defined by the Food and Drug Administration. You may think you can eat larger servings of these lower-carb products but think again. They tend to cost more and aren’t necessary once you get the hang of carb counting the foods you enjoy best. Also, the “low carb” product you choose may have fewer carbs but be very high in fat and calories. Remember, too, that foods labeled “sugar-free” are not carbohydrate-free. Always focus on the number that matters—grams of total carbohydrate per serving—and then decide whether it’s for you.
What are “net carbs”?
A term you may have come across on packaged foods is “net carbs”—another concept promoted by the low-carb diet industry. Net carbs is a number equal to the total grams of carbohydrate minus the grams of fiber, sugar alcohol and glycerin. This marketing practice is not as scientific as it is promotional. It encourages consumers to eat more of the foods claimed to have fewer net carbs. However, people who count only net carbs tend to give themselves permission to overeat when, in fact, they could be eating their favorite foods in portions that work well in a carb-counting routine.
Balance your meals
Spread your day’s carbohydrate allowance throughout your meals and snacks to keep your blood glucose levels even. Eat three to four carb servings at each meal and one to two servings in snacks but make sure you don’t exceed your daily carb budget. (Depending on your current weight and your weight goals, your doctor or educator may make different recommendations.) And remember, a balanced meal consists not only of carbohydrate but also of some protein, vegetables and healthy fats.
Don’t be tempted to save up your carbs for a big feast or special occasion—it doesn’t work. Overloading on carbs at one meal will show up afterwards in your blood glucose. Day-to-day, meal-to-meal glycemic control is your real goal.
Top tips for carbohydrate counting
- Check food labels. This is the only way to count carbs accurately. Note that for glucose control purposes, a serving of carbohydrate equals 15 grams, no matter what the package says about the number of total carbs in one of its servings.
- Spread carbohydrate intake across your day’s meals and snacks. Even consumption will yield more even control of your blood glucose.
- Plan ahead for meals. Try to use recipes or visit restaurants for which you have nutrition information.
- Select a variety of carb sources. Get most of them from the fruits, milk and starches groups.