Diabetes Diet and Nutrition:

Causes of diabetes

There are two types of diabetes. In Type 1 diabetes, the pancreas does not produce insulin, which is needed for the cells to absorb the glucose released into the bloodstream after eating. Glucose is the main sugar found in the blood, as well as the body’s main source of energy. Without insulin, blood glucose levels rise and can seriously damage the eyes, kidneys, nerves, heart, and blood vessels. Untreated, it can lead to blindness, chronic kidney failure, heart attack, and stroke. In Type 2 diabetes, which constitutes 90-95% of the cases, the pancreas produces insulin, but in insufficient amounts. Or, the body is unable to absorb what the pancreas does create. Type 2 diabetes is usually preceded by insulin resistance, a condition that makes the pancreas work harder, thus effectively burning out insulin production over time. The consequences of Type 2 diabetes are no different or less severe than Type 1. Since elevated glucose is the precipitating factor for diabetic health problems, controlling blood glucose levels is fundamental.

Managing blood glucose levels

A diet for diabetes should keep blood glucose from rising too high or dipping too low. Eating too much can cause blood glucose to elevate to unhealthy levels. Conversely, the consequence of glucose levels dropping too low is hypoglycemia, or low blood sugar. This can manifest as nervousness, trembling, weakness, and “brain fog.” Thus, the key is to stabilize blood glucose at a healthy level. To keep your blood glucose levels stabilized, the National Diabetes Information Clearinghouse (NDIC) recommends that you:

• Eat about the same amount of food each day.
• Eat your meals and snacks at about the same times each day.
• Do not skip meals or snacks.

Effect of cholesterol in a diabetes diet

Diabetics are at an increased risk for heart disease as compared to the general population, so it’s important to control cholesterol levels. Since the body can manufacture all the cholesterol it needs, a healthy diabetes diet includes foods low in cholesterol—specifically LDL levels, which have been identified as the main cholesterol-induced risk factor. The LDL deposits in diabetics bond with the excessive glucose and stick to arteries more readily, increasing the chances of plaque deposits and damage to the arterial wall. A healthy amount of LDL in the blood is less than 100 mg/dL.

Aside from lowering the LDL levels, raising HDL cholesterol (the “good” cholesterol) also lowers the risk of heart problems, since HDL is responsible for moving cholesterol from all parts of the body back to the liver for eventual removal from the system. People with diabetes have lower HDL levels to begin with. According to the American Diabetes Association (ADA), an HDL level of 40 mg/dL and above for men, and 50 mg/dL and above for women, is considered protective against heart disease. Lowering triglyceride levels is also instrumental. Triglycerides are fats carried in the blood stream that are associated with low HDL levels. The triglycerides should be below 150 mg/dl for both sexes.

Beneficial foods for a diabetic diet

Since it is more difficult for the cells to interact with insulin in a person who is overweight, a low-fat diet is important for diabetics. The ADA makes some dietary recommendations for maintaining healthy cholesterol and triglyceride ranges:

• Eat less fat, especially less saturated fat (found in fatty meats, poultry skin, butter, 2% or whole milk, ice cream, cheese, palm oil, coconut oil, trans fats, hydrogenated oils, lard, and shortening).
• Choose lean meats and meat substitutes.
• Switch to low-fat or fat-free dairy products.
• Eat at least 5 servings of fruits and vegetables each day.
• Cut back on foods that are high in cholesterol (such as egg yolks, high-fat meat and poultry, and high-fat dairy products).
• Choose the kinds of fat that can help lower cholesterol, such as olive or canola oil. Nuts also have a healthy type of fat.
• Eat fish two or three times a week, choosing kinds that are high in heart-protective fat (such as tuna and salmon).
• Cook using low-fat methods (such as baking, roasting, or grilling foods or by using cooking sprays).
• Eat more foods that are high in fiber (such as oatmeal, oat bran, dried beans and peas like kidney beans, fruits, and vegetables).
• Eat less salt and sodium.

The Diabetes Food Pyramid

The ADA’s Diabetes Food Pyramid groups foods according to their carbohydrate and protein content, as well as by frequency of use in meals. The aim is to have about the same carbohydrate content per serving. Paying attention to serving sizes is integral to maintaining healthy blood glucose levels; see the ADA’s website in references & resources. Here is the breakdown of recommended servings per day, from the website:

• Grains and starches—6 to 11 servings per day. This group includes bread, cereal, rice, and pasta. The starchy vegetables potatoes, peas, and corn are included here, as are dried beans such as pinto beans and black-eyed peas, because they have a carbohydrate content equivalent to one slice of bread. They should be counted as carbohydrates for the meal plan.
• Vegetables—at least 3 to 5 servings per day. Spinach, chicory, sorrel, Swiss chard, broccoli, cabbage, bok choy, brussel sprouts, cauliflower, kale, carrots, tomatoes, cucumbers, and lettuce all belong to this group.
• Fruit—2 to 4 servings per day. The ADA emphasizes blackberries, cantaloupe, strawberries, oranges, apples, bananas, peaches, pears, apricots, and grapes.
• Milk—2 to 3 servings per day. Again, the emphasis here is on low- or non-fat milk.
• Meat and meat substitutes—4 to 6 ounces per day, divided between meals. Cut all the visible fat off the meat before cooking or eating, and keep the portion sizes small (a 3-ounce serving is the size of a deck of playing cards). Meat replacements include tofu, eggs, dried beans, cheese, cottage cheese, and nut butters.
• Fats, sweets, and alcohol— Potato chips, candy, cookies, cakes, crackers, and fried foods belong to this group. Keep your servings of these foods small and save them for a special treat.

Glycemic Index Diet

The Glycemic Index Diet (GI Diet) ranks foods according to their Glycemic Index, which is the rate at which they break down in the body to form glucose. High GI foods break down rapidly, spiking blood sugar levels and leaving you craving more in a short period of time. Low GI foods break down more slowly, leaving you feeling satisfied for a longer period of time. The low GI foods are the focus of the Glycemic Index diet.

Examples of low GI foods are fruits, vegetables, whole grains, legumes, nuts, lean meats, and low-fat dairy products, all of which have a high nutritional value and provide prolonged energy release. High GI foods on the other hand, such as sugar and white flour products, are highly refined and processed, and have been stripped of essential nutrients.

People trying to lose weight are advised to avoid the high GI foods, eat the intermediate foods sporadically, and eat as much of the low index foods as they want.

The following ranges help dictate people’s food choices:

Glycemic Index Range
Low	55 or less
Intermediate	55–70
High	70 or higher

Is the Glycemic Index Diet always good for diabetes?

The GI diet is definitely useful for diabetics striving to keep their blood sugar regulated. But low GI foods tend to be high in fat. Cheese pizza, for instance, has a relatively low GI Index of 60, yet would break just about all the rules for someone with heart disease. Conversely, caramel-flavored rice cakes, a fibrous, low-fat, low-calorie food, rate an 82 on the GI Index. Since obesity and heart disease are common correlates of diabetes, use the Glycemic Index as a reference for monitoring blood glucose levels, yet do not depend on it’s measurement values to keep weight off—an imperative for diabetics!

Also be aware that different factors affect the GI Index of a food, such as what other foods are eaten with it and how it is prepared. This makes it a little more challenging to plan meals. Apples with the peels on, for example, have a lower GI Index than when skinned. Another indicator to consider is the glycemic load, derived from multiplying the GI Index of a food by the total carbohydrate content of one serving. This gives you a fuller picture by showing you not only how quickly the food breaks down into sugar, but how much of it is in a serving. A food with a high GI and a low carb content wouldn’t cause as dramatic a rise in blood glucose as the same food with a high carb content.

Finally, make sure when checking a food’s Glycemic Index that the reference food—the standard to which the others are compared—is glucose itself. Glucose has a GI of 100, and most systems use it as the referent, with no other foods scoring higher. Some GI Indexes, however, use white bread as the highest indicator, and rate it at 140.

The following table, adapted from the International Table of Glycemic Index 2002, lists the GI rankings for some foods, on a scale of 100:

Glycemic values
Rice cakes, caramel-flavored	82	Pizza, cheese	60
Cake doughnut	76	Sweet corn, boiled	60
Bagel, plain and white	72	Pound cake	54
Whole-wheat bread	69	Potato chips, plain	51
Croissant	67	Carrots	47
Macaroni and cheese, boxed	64	Grapes	43

Related links for preventing and healing diabetes

Type 2 Diabetes: What Is It? – This page sponsored by the non-profit Nemours Foundation gives a basic description of the causes of diabetes. (kidshealth.org)

Diabetes, Cholesterol & Heart Disease – Describes how diabetics face an increased challenge in regards to cholesterol and hear disease. (American Diabetes Association)

What I Need to Know About Diabetes and Eating – This service of the National Institutes of Health provides information on each of the food groups as it relates to diabetes, including serving sizes and how to eat them in a healthy diet. Also explains how food affects glucose levels. (National Diabetes Information Clearinghouse)

Using the Diabetes Food Pyramid – The USDA’s “My Pyramid” adapted for people with diabetes or who are focused on diabetes prevention. (American Diabetes Association)

Diabetes: Heart Disease and Stroke – Explores the link between diabetes and heart disease. ( American Diabetes Association)

About the GI Diet – A commercial site by Rick Gallop, who adapted the GI Index to his diet and wrote a book about it. (gidiet.com)

Glycemic Index (GI) – Explains what the Glycemic Index is and what the factors are that determine a food’s Glycemic Index. (healthcastle.com)

Glycemic Index Diet – Further information on the GI Diet by the Mayo Clinic Medical Services. (Mayo Clinic)

John Dorsey created this article with contributions from Gina Kemp, M.A. Last modified on: 2/13/07.