Sansum Diabetes Research Institute

Nutrition plays a key role in diabetes management. The goal of nutrition therapy is to achieve and maintain normal blood sugar (glucose) levels and optimal nutrition. The purpose of controlling blood glucose is to prevent long-term complications of uncontrolled diabetes. This is done by balancing food intake, medication, managing stress levels and exercise. Attaining and maintaining a reasonable weight also helps control blood glucose levels. Blood glucose is directly related to how well your body uses and responds to the foods you eat. Since most people eat food several times a day, it is important to know how the food you eat affects your blood glucose.

How it works:
When we eat, the macronutrients in food (proteins, fats, and carbohydrates) are broken down into simpler, more easily absorbed chemicals. One of these chemicals is a form of simple sugar, called glucose, which comes from eating sugar and starches, which are known as carbohydrates. Once broken down into glucose, it circulates in the blood stream where it is available for body cells to use as "fuel". The blood carries the glucose or sugar throughout the body. As food is digested and broken down, blood glucose levels rise. In response to this rise in blood glucose, in a non-diabetic person, an organ called the pancreas (found just behind the stomach) releases insulin into the bloodstream. Insulin signals the body tissues to metabolize, or burn, the glucose for fuel, causing blood glucose levels to return to normal. Diabetes occurs when the pancreas stops making enough insulin or the body doesn't use the insulin properly to metabolize the glucose and blood glucose remains higher than normal.

Controlling blood glucose levels should include these goals:

Frequent monitoring of blood glucose
Knowing the carbohydrate content of foods
Practice stress reduction techniques
Planning a diet and exercise plan that controls blood glucose levels

Meal Planning:
Carbohydrate, protein and fat are the main nutrients in food. These nutrients contain calories, which the body uses as energy. These nutrients affect blood glucose in different ways. Carbohydrates have the most effect on blood glucose level. You can help control your blood glucose through the foods you choose. You do not need to eat special foods.

Limit the carbohydrates in your meals and snacks. If you control the amount of carbohydrate you eat and when you eat it, your blood glucose levels will become more consistent. Carbohydrate counting is a meal-planning tool for people with diabetes. You can achieve and maintain normal or near-normal blood glucose levels by including these nutritional principles in your treatment plan:

Reduce carbohydrates to 30-45g with meals, and no more than 15g with snacks.

Balance your meals with carbohydrate, protein and fat.

Select foods that are low in saturated and trans fats.

This must be a life-long lifestyle change in order to consistently control blood glucose levels and prevent long-term complications of uncontrolled diabetes.

Carbohydrates: Affect blood glucose levels. Starches, milk, fruit and vegetables all contain carbohydrate.

Starch is in breads, tortillas, pasta, cereals, potatoes, corn, peas, and legumes.
Fruits and milk contain naturally occurring sugars.
Other foods that contain carbohydrates are foods with added sugars, desserts, candy, jams, and jellies.
Non-starchy vegetables (i.e. asparagus, green beans, carrots, tomatoes, lettuce) contain very little carbohydrate and do not raise blood glucose levels significantly.

All of these carbohydrates turn into glucose. Eating the same amount of carbohydrate with meals and snacks daily helps control blood glucose levels. Too much carbohydrate in a meal or snack at one time can cause a high blood glucose level. Even though carbohydrate affects blood glucose the most, you also need to be aware of how much protein and fat you eat.

Glycemic Index and Glycemic Load:
These are helpful tools to make better choices when it comes to consuming carbohydrates. Both the glycemic index and glycemic load take into consideration the type of carbohydrate (simple vs. complex), the form it is prepared in (example: flour vs. whole, intact grains), the portion size of the carbohydrate food (quantity) and the combination of foods with which it is being consumed.

Protein: Protein foods have little effect on blood glucose levels when eaten in moderate quantities. Recent research shows that 15 to 30 percent of your total daily caloric intake should be from protein, either plant or meat sources. People with kidney disease (diabetic nephropathy) should consult with their physician for individual protein needs.

Protein is found in meats, poultry, fish, eggs, tofu and cheese.

Fat: Fat has little effect on blood glucose levels. However, fat delays the rate at which your stomach empties which can affect the rate at which the carbohydrate is absorbed. Excess fat can also create a temporary state of insulin resistance.

The main source of fats are: margarine, butter, oils, nuts, seeds, avocado and salad dressing.

In the recent past, fat had a bad reputation as something to be strictly avoided. Research shows that not all fats are bad. Recommended daily amounts of fat differ, depending on whether you are at your desired weight, overweight, or have high blood fat (cholesterol) levels. There are also restrictions on the types of fat you should eat and whether the fat should be saturated, polyunsaturated, or monounsaturated. More recent recommendations caution to avoid saturated fats and what are known as "trans" fats found in processed and convenience foods. Too much fat contributes to excess calories and can make controlling weight difficult.

In small quantities fats are an important part of a healthy eating plan. Dietary fat is required for growth, cells, membranes, and is stored as an emergency source of energy when eaten in excess. Current recommendations for fat intake are:

Consume less than 10 percent of calories from saturated fatty acids and less than 200mg /day of cholesterol, and avoid trans fatty acid consumption.
Keep total fat intake between 20 to 35 percent of calories, with most fats coming from sources of polyunsaturated Omega-3 fatty acids and monounsaturated fatty acids, such as fish, nuts, and olive and canola oils.
When selecting and preparing meat, poultry, dry beans, and milk or milk products, make choices that are lean, low-fat, or fat-free.
Limit intake of products containing "hydrogenated" oils.

Since fat is a concentrated source of calories, one of the best ways to reduce calories (and weight) is to reduce your intake of total fat, which works particularly well when you also increase your exercise. Read food labels to identify and avoid saturated and trans fats and identify the low- and lower-fat options in the market.

Of importance are the healthy fats, known as omega-3 fatty acids. The Mediterranean diet has gained much popularity due to its wide use of "healthy" fats. Good sources of these essential fatty acids include:

flaxseeds, flaxseed oil, flaxseed meal, hempseed oil, hempseeds, walnuts, pumpkin seeds, Brazil nuts, sesame seeds
avocados, some dark leafy green vegetables (kale, spinach, purslane, mustard greens, collards, etc.),
olive oil, canola oil (cold-pressed and unrefined), soybean oil, wheat germ oil
salmon, mackerel, sardines, anchovies, albacore tuna, and others.

If you have elevated levels of blood fats, such as cholesterol or triglycerides, your doctor and dietitian may recommend that you increase the percentage of monounsaturated fat and Omega-3 FA, while reducing your intake of trans, saturated or polyunsaturated types of fat.

Sugar and Sweeteners: Your individualized eating plan should give priority to total carbohydrate, rather than sources of that carbohydrate. The guidelines also state that other nutritive sweeteners (corn syrup, fruit juice, molasses, honey, dextrose, and maltose) do not have any significant advantage or disadvantage over simple sugar in terms of calories or blood glucose response. Fructose, however, may offer some advantages as a sweetener, but is has the potential for creating unwanted side effects.

"Scientific evidence has shown that the use of sucrose (table sugar) as part of the meal plan does not impair blood glucose control in individuals with type 1 or type 2 diabetes". What the experts are saying is that sugar can be part of a well balanced meal that contains protein, fat, and carbohydrates. A high-sugar food should not be eaten alone as a snack because it can send blood glucose levels soaring. As part of a well balanced meal, however, sugar (in place of other carbohydrates) does not have this effect on post-meal blood glucose levels. The same experts also report that sugar and sugar-containing foods must be substituted for other carbohydrates in your eating plan, not simply added to an already balanced meal.

Sugar Alcohols: Alternative sugars are sugar alcohols. They have half the calories and grams of carbohydrate that regular sugars have. Sugar alcohols include: sorbitol, mannitol, xylitol, isomalt and hydrogenated starch hydrosylates. They are absorbed slowly causing blood glucose to rise more slowly. These sugars may have unpleasant side affects in some individuals such as gastric discomfort.

Novel Sugars: Tagatose and Trehalose.

Sugar Substitutes: Sugar substitutes help satisfy sweet cravings without causing blood glucose to rise. Some sugar substitutes on the market are: Saccharin (Sweet 'N Low®), Aspartame (Nutrasweet® or Equa®), Acesulfame K (Sweet One®), and Sucralose (Splenda®).

Natural Sweetener: Stevia is a natural alternative sweetener.

Fiber: Dietary fiber intake of 25 to 50 grams per day from a variety of food sources is recommended for all adults, including those with diabetes. The effect of dietary fiber on blood glucose control varies in individuals. Adding soluble fiber to your diet may offer some benefit.

Sodium: The guidelines recommend that sodium restrictions be the same for people with diabetes as for the general population - no more than 2,400 milligrams per day or less is recommended.

Alcohol: Under normal circumstances blood glucose control will not be affected by moderate use of alcohol, when diabetes is well controlled. Keep in mind, however, that alcohol may increase the risk of hypoglycemia. If consumed, alcohol should be consumed with a meal.

If you inject insulin, your dosage may need to be adjusted to account for alcohol consumption. Those who inject insulin should limit themselves to two alcoholic drinks a day. A typical "drink" is twelve ounces of beer, four ounces of wine, or one and a half ounces of liquor. When possible, choose light beers and dry wines because they have fewer calories. Watch out for sugary drinks, like wine coolers, and mixed drinks made with regular soda or juice.

If you are working to control your weight, remember that alcoholic beverages contain "empty" calories that must be counted in your daily total but do not provide any nutritional value.

If you need more information or help in learning how to eat wisely, SDRI offers free nutrition classes for people with diabetes - Nutrition & Diabetes Classes and educational materials