To print: Select File and then Print from your browser's menu
Looking Beyond “Low-Carb” Labels
I couldn’t believe it. Right there on the grocery store shelf was a mint chocolate candy bar with no sugar. I was so excited I almost ate it before checking out. Three hours later, however, I felt a lot less enthusiastic about this product. Even with no sugar, it had somehow caused my blood glucose level to skyrocket. How had this happened?
Like so many hopeful consumers before me, I found out the hard way that “no sugar” does not necessarily mean “no calories” or “no carbohydrate.” Had I read the Nutrition Facts panel on my candy bar or even read the ingredients list, I might have realized that this treat, even though sugar-free, would have an effect on my blood glucose level.
Understanding label claims
Here are some label claims that have a specific, legal meaning:
Sugar free. Foods bearing this claim must have less than 0.5 grams of sugar per serving. However, they may contain carbohydrate from other sources.
No added sugar, No sugar added, Without added sugar. These claims mean that no sugar or ingredients that contain sugar such as fruit juice or applesauce are added to a food during processing or packing. Additionally, the processing itself cannot increase the sugar content of the food, and the product that the food is replacing must normally contain added sugars.
Reduced sugar. Foods bearing this claim must have at least 25% less sugar per serving than a comparable reference food. For example, reduced-sugar ice cream would have at least 25% less sugar than regular ice cream.
The following terms have been invented by food manufacturers to suggest that their products contribute few grams of carbohydrate to the diet, but none of them has been defined by the U.S. Food and Drug Administration (FDA), so they have no legal meaning: net carbs, impact carbs, effective carbs, low carb, reduced carb, and carb free.
Food manufacturers usually calculate the “net,” “impact,” or “effective” carbs by subtracting all of the grams of fiber, all of the grams of sugar alcohols (see “Low-Carbohydrate Comparison”), and all of the grams of glycerine (also known as glycerin and glycerol) from the total carbohydrate amount. While it’s true that fiber is not absorbed and does not affect blood glucose levels, most diabetes nutrition experts recommend subtracting grams of fiber from total carbohydrate only if there are more than 5 grams of fiber per serving. Sugar alcohols, on the other hand, do get at least partially absorbed, do contain calories, and do affect blood glucose levels. And glycerine, which is used both to sweeten foods and to make them moist, provides as many calories per gram as sugar and is considered a carbohydrate by the FDA. However, many food manufacturers contend that glycerine has a negligible effect on blood glucose levels.
Sugar-free or “low-carb” foods aren’t necessarily all bad. Some may have fewer grams of carbohydrate than their regular counterparts and may fit well into your meal plan. Some may be significantly lower in calories. But it’s important to know what’s in them and to understand how they can affect your blood glucose control if you’re going to include them in your diet.
Sugar alcohols. Sugar alcohols, which are often used as ingredients in “low-carbohydrate” foods, are nutritive sweeteners. In spite of label claims suggesting otherwise, sugar alcohols contribute calories and carbohydrate to the diet, and they raise blood glucose levels. Most sugar alcohols provide fewer calories than sugar (2–3 calories per gram rather than 4 calories per gram). They are also absorbed into the bloodstream more slowly than sugar, so they do not raise blood glucose levels as high, and they require less insulin to metabolize. Sugar alcohols are also less sweet than sugar, and they add bulk and moisture to foods, so they are often used in combination with nonnutritive sweeteners in foods and in products such as cough drops. Some products also combine sugar alcohols with sugar or other caloric sweeteners to create a product that’s somewhat lower in carbohydrate than one sweetened only with sugar.
Food manufacturers may voluntarily list the number of grams of sugar alcohols in a serving of food in the Nutrition Facts panel. However, if a claim such as “sugar-free” or “no added sugar” is made on the package, the sugar alcohol content must be shown in the Nutrition Facts panel, according to FDA regulations. If only one type of sugar alcohol is used, the specific name may appear in the Nutrition Facts panel, but if more than one type is used, the term “sugar alcohols” must be used. Most diabetes nutrition experts recommend counting half the grams of sugar alcohols in the portion of food you eat toward your carbohydrate total for the meal or snack.
Common sugar alcohols include erythritol, hydrogenated starch hydrolysates, isomalt, lactitol, maltitol, mannitol, sorbitol, and xylitol. If eaten in excess, sugar alcohols can cause gastrointestinal symptoms such as gas or diarrhea. The American Dietetic Association advises that more than 50 grams per day of sorbitol or more than 20 grams per day of mannitol “may cause diarrhea.” However, individual tolerance of these substances varies, and some people may be affected by as little as 10 grams of sorbitol a day. Because of these side effects, foods that contain sorbitol or mannitol and are likely to be eaten in amounts that could produce such an effect must bear the statement “Excess consumption may have a laxative effect.”
Tagatose. A relatively new reduced-calorie sweetener on the US market, tagatose occurs naturally in a variety of foods, including some dairy products, and is 92% as sweet as sucrose (table sugar). Because it is not completely absorbed by the body, it provides only around 38% of the calories of sucrose, but this incomplete absorption can lead to bloating, nausea, flatulence, and diarrhea.
Trehalose. Another relative newcomer on the US sweetener market, trehalose is a sugar that is naturally present in foods such as mushrooms and lobster. It is commercially produced from cornstarch and is approved for use in a variety of foods and beverages including nutrition bars and sports drinks. According to preliminary studies by Cargill, the company that produces trehalose, it may cause a lower insulin response than glucose. However, trehalose is only about half as sweet as sucrose.
Fructose. This sugar occurs naturally in foods such as fruit, honey, and some vegetables. Products sweetened with fructose are sometimes marketed with the claim that they raise blood glucose levels less than similar products sweetened with sucrose. It is true that pure fructose has little effect on blood glucose levels and, because of the way it’s metabolized, can be used by the body for energy without insulin. However, fructose has the same number of calories per gram as sucrose or glucose, so portion size remains important, and it’s a good idea to check the label for other ingredients, such as white flour, that have a more pronounced effect on blood glucose level.
Most people are currently advised to get less than 10% of their calories from saturated and trans fats. For a person who eats 1800 calories per day, that’s less than 20 grams of saturated and trans fats. For a person who eats 2,000 calories per day, that’s less than 22 grams of saturated and trans fats.
People who have coronary heart disease or high LDL cholesterol (100 mg/dl or higher) are advised to consume an even smaller amount of saturated and trans fats: less than 7% of calories. That’s less than 14 grams of saturated and trans fats in an 1800-calorie-per-day diet and less than 15 grams in a 2,000-calorie-per-day diet.
Counting the grams of saturated fats in packaged food products is easy because saturated fat content is listed in the Nutrition Facts panel. Counting the grams of trans fats became easy in January 2006, when a new FDA labeling regulation made it mandatory to list them in the Nutrition Facts panel. Some food manufacturers have removed trans fats from their products (and labeled the products “trans fat free”). If a food is not labeled “trans fat free” and trans fats are not listed in the Nutrition Facts panel, look at the ingredients list for hydrogenated or partially hydrogenated oils. If they are present, the product almost certainly contains some trans fats.
Although saturated fats in general are to be avoided, there is a ray of light where the fat contained in chocolate is concerned. While this fat, which comes from cocoa butter, is highly saturated, about one-third of it is oleic acid, a heart-healthy monounsaturated fat, and another third is stearic acid, a saturated fat that does not seem to affect cholesterol levels. And chocolate, particularly dark chocolate, may actually have some cardiovascular health benefits. This is because cocoa, one of the main ingredients in chocolate, is a plant-based product that is rich in flavonoids. According to a study published in the February 2003 issue of Journal of the American Dietetic Association, the flavonoids in chocolate have a variety of healthful effects, primarily as antioxidants (antioxidants, it is believed, help reduce damage done to body cells by substances called free radicals). Adequate consumption of flavonoids may reduce the harmful effects of LDL cholesterol and perhaps even lower blood pressure. This should not be taken as a license to eat chocolate with abandon, however, since simply adding chocolate to your diet will likely result in weight gain. Most processed chocolate contains a fair share of calories, fat, and sugar.
In general, a regular, 12-ounce beer provides about 150 calories and 13 grams of carbohydrate and is about 5% alcohol by volume. A light beer provides about 100 calories and 5 grams of carbohydrate (although some have more) and is about 4% alcohol by volume. A “low-carbohydrate” beer provides about 95 calories and 3 grams of carbohydrate and, like light beer, is about 4% alcohol by volume.
The fact that beers marketed as “low-carbohydrate” have about the same amount of alcohol per serving as regular or light beer is worth noting for people who have diabetes. This is because drinking alcohol, particularly on an empty stomach, can cause low blood glucose (hypoglycemia). Unlike carbohydrate, protein, and fat, alcohol is not broken down through the process of digestion. Instead, it is absorbed into the bloodstream directly through the lining of the stomach and wall of the small intestine. If there is no food in the stomach, alcohol is absorbed quickly; the presence of food slows absorption somewhat. Once in the bloodstream, alcohol tends to make insulin and other blood-glucose-lowering drugs “work” harder, which can lead to hypoglycemia.
Another way in which alcohol raises the risk of hypoglycemia is by interfering with the normal release of glucose by the liver when blood glucose levels are low. The liver metabolizes most of the alcohol a person consumes, and while it is processing alcohol, that task takes first priority. The liver breaks down alcohol at a rate of about half an ounce per hour, so it takes about two hours to metabolize one ounce of alcohol — the amount in about 12 ounces of beer. Not only is the liver not releasing glucose while processing alcohol, but it is also not adding to its stores of glycogen (a storage form of glucose), which can raise the risk of hypoglycemia hours after drinking.
Exercising while drinking also increases the risk of hypoglycemia since physical activity also tends to lower blood glucose levels.
To lower the risks associated with drinking alcohol, diabetes experts offer the following, commonsense guidelines:
No free lunch
Low-carbohydrate foods and beverages may offer some new options for your meal plan, but they’re not necessarily “free” foods. When sampling new, “low-carb” products, keep these tips in mind:
Statements and opinions expressed on this Web site are those of the authors and not necessarily those of the publishers or advertisers. The information provided on this Web site should not be construed as medical instruction. Consult appropriate health-care professionals before taking action based on this information.