The American Diabetes Association (ADA) guideline for nutrition therapy recommends:
The two major forms of diabetes are type 1, previously called insulin-dependent diabetes mellitus (IDDM) or juvenile-onset diabetes, and type 2, previously called non-insulin-dependent diabetes mellitus (NIDDM) or adult-onset diabetes. There are other forms of diabetes that account for about 1 out of every 20 patients with diabetes.
Both type 1 and type 2 diabetes share one central feature: elevated blood sugar (
In type 1 diabetes, the pancreas does not produce insulin. Onset is usually in childhood or adolescence, but can occur in adults. Type 1 diabetes is considered an autoimmune disorder meaning your own immune system is involved in causing the disease.
Patients with type 1 diabetes need to take insulin. Dietary control in type 1 diabetes is very important and focuses on balancing food intake with insulin intake and energy expenditure from physical exertion.
Type 2 diabetes is the most common form of diabetes, accounting for 90% to 95% of cases. In type 2 diabetes, the body does not respond normally to insulin, a condition known as insulin resistance, which means your body needs to make more insulin. Over time, your ability to make high levels of insulin decreases and then type 2 diabetes develops. In type 2 diabetes, the initial effect is usually an abnormal rise in blood sugar right after a meal (called impaired glucose tolerance OR postprandial hyperglycemia).
Patients whose blood glucose levels are higher than normal, but not yet high enough to be classified as diabetes, are considered to have pre-diabetes (also called impaired fasting glucose). It is very important that people with pre-diabetes control their weight to stop or delay the progression to diabetes.
Obesity is common in patients with type 2 diabetes, and this condition appears to be related to insulin resistance. The primary dietary goal for overweight or obese type 2 patients is weight loss and maintenance. With regular exercise and diet modification programs, many people with type 2 diabetes can minimize or even avoid medications. Weight loss medications or bariatric surgery may be appropriate for some patients. Most patients only need to lose 5% to 10% body weight to cause a big improvement in control of their blood sugars.
Lifestyle changes of diet and exercise are extremely important for people who have pre-diabetes, or who are at high risk of developing type 2 diabetes. Lifestyle interventions can be very effective in preventing or postponing the progression to diabetes. These interventions are especially important for overweight or obese people. Even moderate weight loss can help reduce diabetes risk.
The American Diabetes Association recommends that people at high risk for type 2 diabetes lose weight (if necessary), engage in regular physical exercise, and follow a diet with reduced calories and lower dietary fat. High-fiber (14g fiber for every 1,000 calories) and whole-grain foods are recommended for prevention. These strategies can help reduce type 2 diabetes risk.
Patients who are diagnosed with diabetes need to be aware of their heart health nutrition and, in particular, controlling high blood pressure and cholesterol levels.
For people who have diabetes, the treatment goals for a diabetes diet are:
The American Diabetes Association's nutritional guidelines recommend:
There is no such thing as a single diabetes diet. Patients should meet with a professional dietitian to plan an individualized diet within the general guidelines that takes into consideration their own health needs.
For example, a patient with type 2 diabetes who is overweight and insulin-resistant may need to have a different carbohydrate-protein balance than a thin patient with type 1 diabetes in danger of kidney disease. Because regulating diabetes is an individual situation, everyone with this condition should get help from a dietary professional in selecting their best diet.
Recommended eating plans include Mediterranean, vegetarian, and lower-carbohydrate diets. (Vegetarian diets can be tricky to balance because vegetarian protein sources contain carbohydrates while animal protein sources do not.) However, there is no evidence that one plan is better than another.
What is most important is to find a healthy eating plan that works best for you and your lifestyle and food preferences. Whatever diet plan you follow, try to eat a variety of nutrient-rich food in appropriate portion sizes.
Several different dietary methods are available for controlling blood sugar in type 1 and insulin-dependent type 2 diabetes:
Both low blood sugar (hypoglycemia) and high blood sugar (hyperglycemia) are of concern for patients who take insulin. It is important, therefore, to monitor blood glucose levels carefully as instructed by your provider. Depending on your type of diabetes and the medications you take you may be asked to measure your blood sugar from zero to seven times a day.
In general, most adult patients should aim for the following measurements goals (patients with gestational diabetes may have different goals):
Hemoglobin A1C (also called HbA1c or HA1c) is measured periodically up to every 3 months, or at least twice a year, to determine the average blood-sugar level over the lifespan of the red blood cell. While point of care (fingerstick) self-testing provides information on blood glucose for that moment, the A1C test shows how well blood sugar has been controlled over a period of several months. For most adults with well-controlled diabetes, A1C levels should be at around 7%. For children, A1C should be less than 7.5%. (For people who do not have diabetes, normal A1C is <6%.)
Other tests are needed periodically to determine potential complications of diabetes, such as high blood pressure, unhealthy cholesterol levels, and kidney problems. Such tests may also indicate whether current diet plans are helping the patient and whether changes should be made. Periodic urine tests for albumin and blood tests for creatinine can indicate a future risk for serious kidney disease.
Every year thousands of new packaged foods are introduced, many of them advertised as nutritionally beneficial. It is important for everyone, most especially people with diabetes, to be able to differentiate advertised claims from truth.
In 2014, the FDA announced that it would be revising food labels to better reflect new dietary requirements, and highlight key information such as calories and serving sizes. The proposed labels will include information on fats, cholesterol, protein, sodium, total carbs, and dietary fiber. A new feature will be the distinction of sugars and "added sugars" to help consumers better understand how much sugar is naturally in the product, and how much has been added. Potassium and vitamin D information will also be required.
Labels show "daily values," the percentage of a daily diet that each of the important nutrients offers in a single serving. This daily value is based on 2000 calories, which is often higher than what most patients with diabetes should have, The serving size on a food label often does not mach the serving size of the diabetic exchange lists. For a person who is carbohydrate counting, a serving size contains 15 grams of carbohydrate. When calculating the serving size information, use only "total carbohydrate;" do not adjust to the diabetic exchange list using sugar or added sugar.
Weighing and measuring food is extremely important to get the correct number of daily calories.
Patients with diabetes should not skip meals, particularly if they are taking insulin. Skipping meals can upset the balance between food intake and insulin and also can lead to low blood sugar and even weight gain if the patient eats extra food to offset hunger and low blood sugar levels.
The timing of meals is particularly important for people taking insulin:
Compared to fats and protein, carbohydrates have the greatest impact on blood sugar (glucose). Except for dietary fiber, which is not digestible, carbohydrates are eventually broken down by the body into glucose. Carbohydrate types are either complex (as in starches) or simple (as in fruits and sugars).
Complex carbohydrates are broken down more slowly by the body than simple carbohydrates. They are more likely to provide other nutritional components and fiber:
Fiber is an important component of many complex carbohydrates. It is found only in plant-based foods. There are two types of fiber:
Simple carbohydrates, or sugars (either as sucrose or fructose), add calories, increase blood glucose levels quickly, and provide little or no other nutrients:
People with diabetes should avoid products listing more than 5 grams of sugar per serving, and some doctors recommend limiting fruit intake. Although moderation is important, fruits are an important part of any diet. They provide essential vitamins, minerals, and antioxidants, as well as fiber. You can limit your fructose intake by consuming fruits that are relatively lower in fructose (cantaloupe, grapefruit, strawberries, peaches, bananas) and avoiding added sugars such as those in sugar-sweetened beverages. Fructose is metabolized differently than other sugars and can significantly raise triglycerides, though usually a large intake of fructose is needed to do this.
In addition, limit processed foods with added sugars of any kind. Pay attention to ingredients in food labels that indicate the presence of added sugars. These include terms such as sweeteners, syrups, fruit juice concentrates, molasses, and sugar molecules ending in "ose" (like dextrose and sucrose).
Artificial sweeteners use chemicals that mimic the sweetness of sugar. They include aspartame (NutraSweet, Equal), sucralose (Splenda), saccharine (Sweet'N Low), and rebiana (Truvia). (Rebiana is an extract derived from the plant stevia.) These products do not contain calories and do not affect blood sugar. Artificial sweeteners can help with weight control, but it is important not to consume extra calories elsewhere.
Some people plan their carbohydrate intake using a system called carbohydrate counting. It is based on these premises:
The basic goal of carbohydrate counting is to balance insulin with the amount of carbohydrates eaten in order to control blood sugar (glucose) levels after a meal. There are several options for counting carbohydrates. It's best to work with a registered dietitian.
A dietitian can create a meal plan that accommodates the patient's weight and needs. Many patients with type 1 diabetes work with their providers to determine a carbohydrate to insulin ratio. This special calculation tells the patient how much insulin they need to take to cover a certain amount of carbohydrate in the meal. A common ratio would be 1 unit of insulin for 15 grams of carbohydrate. Then if you choose a meal with 60 grams of carbohydrate you know you need 4 units of insulin to match the carbohydrates and prevent the meal from increasing your blood sugar level. When patients learn how to count carbohydrates and adjust insulin doses to their meals, many find this system more flexible, more accurate in predicting blood sugar increases, and easier to plan meals than other systems.
The glycemic index helps determine which carbohydrate-containing foods raise blood glucose levels more or less quickly after a meal. The index uses a set of numbers for specific foods that reflect greatest to least delay in producing an increase in blood sugar after a meal. The lower the index number, the better the impact on glucose levels. This system is artificial in that the number is calculated when eating only that food. The index for mashed potato is 72, but eating the same amount of mashed potato with gravy, green beans and grilled chicken breast would change the absorption time significantly. The index also does not account for variation in food preparation. The lower (good) glycemic index of brown rice can be increased (bad) just be increasing the cooking time.
There are two indices in use. One uses a scale of 1 to 100 with 100 representing a glucose tablet, which has the most rapid effect on blood sugar. [See Table: "The Glycemic Index of Some Foods," below.] The other common index uses a scale with 100 representing white bread (so some foods will be above 100).
Choosing foods with low glycemic index scores may have a modest effect on controlling the surge in blood sugar after meals. Substituting low- for high-glycemic index foods may also help with weight control.
One easy way to improve glycemic index is to simply replace starches and sugars with whole grains and legumes (dried peas, beans, and lentils). However, there are many factors that affect the glycemic index of foods, and maintaining a diet with low glycemic load is not straightforward.
No one should use the glycemic index as a complete dietary guide, since it does not provide nutritional guidelines for all foods. It is simply an indication of how the metabolism will respond to certain carbohydrates.
The Glycemic Index of Some Foods
Based on 100 = a Glucose Tablet
Kidney (dried and boiled, not canned)
Spaghetti (boiled 5 minutes)
Spaghetti (boiled 15 minutes)
Note. These numbers are general values, but they may vary widely depending on other factors, including if and how they are cooked and foods they are combined with.
Low carbohydrates diets generally restrict the amount of carbohydrates but do not restrict protein and fat sources. The larger variation usually becomes the fat content as the percent of calories from protein does not vary as much between diets:
Protein is important for strong muscles and bones. Eating protein may help people feel fuller and thus reduces overall calories. In addition, protein consumption helps the body maintain lean body mass during weight loss. However, some types of protein (red meat, full-fat dairy products) are high in saturated fat, which can be bad for the heart and can make weight gain more likely.
Good sources of protein include fish, skinless chicken or turkey, low-fat dairy products, soy (tofu), and legumes (such as kidney beans, black beans, chick peas, and lentils).
Legumes are one of the healthiest types of foods, and are an important source of protein for vegetarians. Legumes include all sorts of beans such as black beans, pinto beans, lentils, and chickpeas. Dried beans can take more time to prepare, but they have less sodium (salt) than canned varieties. You can also reduce sodium by draining and rinsing canned products.
Soy protein is found in products such as tofu, soy milk, and soybeans. (Soy sauce is not a good source. It contains only a trace amount of soy and is very high in sodium.)
Plant-based proteins are rich in both soluble and insoluble fiber, and have more vitamins and minerals than meat or dairy proteins. They are also low in fat.
Fish is one of the best sources of protein. Evidence suggests that eating moderate amounts of fish (twice a week) may improve triglycerides and help lower the risks for death from heart disease. The healthiest fish are oily fish such as salmon, mackerel, or sardines, which are high in omega-3 fatty acids.
The omega-3 fatty acids contained in fish oil are also available as dietary supplements. However, according to the American Diabetes Association there is no evidence that show these supplements help prevent or treat diabetes. Eating fish is a better way to get omega-3 fatty acids.
Lean cuts of meat are the best choice for heart health and diabetes control. Saturated fat in meat is the primary danger to the heart. The fat content of meat varies depending on the type and cut. Skinless chicken or turkey, which are lower in saturated fat, are better choices than red meat. (Fish is an even better choice.)
A high intake of dairy products may lower risk factors related to type 2 diabetes and heart disease (insulin resistance, high blood pressure, obesity, and unhealthy cholesterol). Some research suggests the calcium in dairy products may be partially responsible for these benefits. Vitamin D contained in dairy may also play a role in improving insulin sensitivity, particularly for children and adolescents. However, because many dairy products are high in saturated fats and calories, it's best to choose low-fat and nonfat dairy items. Some nonfat items have a lot of added sugar - check the label!
Fats can have good or bad effects on health, depending on their chemistry. The type of fat appears to be more important than the total amount of fat when it comes to reducing heart disease, but all fats should be consumed in moderation. All fats, good or bad, are high in calories compared to proteins and carbohydrates. One fat gram provides 9 calories.
Current dietary guidelines for diabetes and heart health recommend that:
Try to replace saturated fats and trans fatty acids with unsaturated fats from plant and fish oils. Omega-3 fatty acids, which are found in fish and a few plant sources, are a good source of unsaturated fats. Fish oils contain the omega-3 fatty acids docosahexaenoic (DHA) and eicosapentaenoic (EPA) acids, which have significant benefits for the heart. Generally, two servings of fish per week provide a healthful amount of these omega-3 fatty acids.
Animal-based foods contain cholesterol, which contributes to heart disease. (However, saturated fat has a much greater impact on cholesterol levels than dietary cholesterol.) High amounts of cholesterol occur in meat, dairy products and shellfish. Although egg yolks contain cholesterol, up to 2 eggs (whole eggs) per day can be healthful for most people and are a good source of protein, iron, and B vitamins.
Plant foods, such as fruits, vegetables, nuts, and grains, do not contain cholesterol. Plant substances known as sterols, and their derivatives called stanols, may reduce cholesterol by blocking its absorption in the intestinal tract. Margarines containing sterols are available.
It is important for everyone to restrict their sodium (salt) intake. People with diabetes should reduce sodium intake to no more than 2300 mg daily (less than 1 teaspoon of salt). Some people may benefit from restricting sodium intake to no more than 1500 mg per day. Limiting or avoiding consumption of processed foods can go a long way to reducing salt intake. Simply eliminating table and cooking salt is also beneficial. The DASH diet is an excellent heart-healthy eating plan that restricts sodium.
Salt substitutes, such as Nu-Salt and Mrs. Dash (which contain mixtures of potassium, sodium, and magnesium) are available, but they can be risky for people with kidney disease or those who take blood pressure medication that causes potassium retention.
Potassium-rich foods are also important for good blood pressure. The best source of potassium is from the fruits and vegetables that contain them. Potassium-rich foods include bananas, oranges, pears, prunes, cantaloupes, tomatoes, dried peas and beans, nuts, potatoes, and avocados.
Patients with diabetes should check with their doctors before increasing the amount of potassium in their diets. Eating too much potassium-rich foods can cause problems for some people. (No one should take potassium supplements without consulting a doctor.) Kidney problems can cause potassium overload, and medications commonly used in diabetes (such as ACE inhibitors or potassium-sparing diuretics) also limit the kidney's ability to excrete potassium.
The American Diabetes Association recommends limiting alcoholic beverages to 1 drink per day for non-pregnant adult women and 2 drinks per day for adult men.
Many studies have noted an association between coffee consumption (both caffeinated and decaffeinated) and reduced risk for developing type 2 diabetes. Researchers are still not certain if coffee protects against diabetes. (If you drink coffee, don't add sugar or creamers, which negate any possible benefits.)
Research has shown that vitamin supplements have no benefit for heart disease or diabetes. Because of the lack of scientific evidence for benefit, the American Diabetes Association does not recommend regular use of vitamin or mineral supplements, except for people who have nutritional deficiencies.
Patients with type 2 diabetes who take metformin (Glucophage, generic) should be aware that this drug can interfere with vitamin B12 absorption. Calcium supplements may help counteract metformin-associated vitamin B12 deficiency.
Generally, manufacturers of herbal remedies and dietary supplements do not need FDA approval to sell their products. Just like a drug, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been a number of reported cases of serious and even lethal side effects from herbal products. Patients should always check with their doctors before using any herbal remedies or dietary supplements.
Traditional herbal remedies for diabetes include bitter melon, cinnamon, fenugreek, and Gymnema sylvestre. Few well-designed studies have examined these herbs' effects on blood sugar, and there is not enough evidence to recommend them for prevention or treatment of diabetes.
Various fraudulent products are often sold on the Internet as "cures" or treatments for diabetes. These dietary supplements have not been studied or approved. The FDA warns patients with diabetes not to be duped by bogus and unproven remedies.
The American Diabetes Association recommends that overweight and obese patients aim for a small but consistent weight loss of ½ to 1 pound per week. A registered dietician can compute a daily calorie goal for you based on your height, weight, age, sex, and activity level. Some registered dieticians are also certified diabetes educators.
Even modest weight loss can reduce the risk of heart disease and diabetes. According to the American Diabetes Association (ADA), low-carbohydrates, low-fat calorie-restricted, or Mediterranean diets may help reduce weight in the short term (up to 2 years). Physical activity and behavior modification are also important for achieving and maintaining weight loss.
Here are some general weight-loss suggestions that may be helpful:
Calorie restriction has been the cornerstone of obesity treatment. Restricting calories in such cases also appears to have beneficial effects on cholesterol levels, including reducing LDL and triglycerides and increasing HDL levels.
The standard dietary recommendations for losing weight are:
Aerobic exercise has significant and particular benefits for people with diabetes. Regular aerobic exercise, even of moderate intensity (such as brisk walking), improves insulin sensitivity. People with diabetes are at particular risk for heart disease, so the heart-protective effects of aerobic physical activity are especially important.
The following are precautions for all people with diabetes, both type 1 and type 2:
The objective of using diabetic exchange lists is to maintain the proper balance of carbohydrates, proteins, and fats throughout the day. Patients should meet with a dietician or diabetes nutrition expert for help in learning this approach.
In developing a menu, patients must first establish their individual dietary requirements, particularly the optimal number of daily calories and the proportion of carbohydrates, fats, and protein. The exchange lists should then be used to set up menus for each day that fulfill these requirements.
The following are some general rules:
The following are the categories on exchange lists:
Each exchange under starches and bread contains about 15 grams of carbohydrates, 3 grams of protein, and a trace of fat for a total of 80 calories. A general rule is that a half-cup of cooked cereal, grain, or pasta equals one exchange. One ounce of a bread product is 1 serving.
The exchange groups for meat and cheese are categorized by lean meat and low-fat substitutes, medium-fat meat and substitutes, and high-fat meat and substitutes. Use high-fat exchanges a maximum of 3 times a week. Fat should be removed before cooking. Exchange sizes on the meat list are generally 1 ounce and based on cooked meats (3 ounces of cooked meat equals 4 ounces of raw meat).
Exchanges for vegetables are 1/2 cup cooked, 1 cup raw, and 1/2 cup juice. Each group contains 5 grams of carbohydrates, 2 grams of protein, and 2 to 3 grams of fiber. Vegetables can be fresh or frozen; canned vegetables are less desirable because they are often high in sodium. They should be steamed or cooked in a microwave without added fat.
Sugars are included within the total carbohydrate count in the exchange lists. Sugars should not be more than 10% of daily carbohydrates. Each exchange contains about 15 grams of carbohydrates for a total of 60 calories.
The milk and substitutes list is categorized by fat content similar to the meat list. A milk exchange is usually 1 cup or 8 ounces. Those who are on weight-loss or low-cholesterol diets should follow the skim and very low-fat milk lists -- while avoiding the whole milk group. Others should use the whole milk list very sparingly. All people with diabetes should avoid artificially sweetened milks.
A fat exchange is usually 1 teaspoon, but it may vary. People, of course, should avoid saturated and trans fatty acids and choose polyunsaturated or monounsaturated fats instead.
Number of Exchanges per Day for Various Calories Levels
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Reviewed By: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.