by Adele H. Hite, M.A.T. and Eric C. Westman, M.D.
Though managing the condition may seem daunting, there is a less complicated dietary solution.
The following made-up scenario represents a situation that is too often repeated in doctors’ examination rooms across the country: Jane Doe, a 54-year-old white female, has her yearly checkup with her family physician, expecting to leave with a clean bill of health. Yes, she has gained some weight in the past few years and is having trouble losing the extra pounds. True, she has been feeling more tired lately, but nothing out of the ordinary. Sure, her blood pressure is up a bit, but she attributes that to her weight gain. When her doctor tells her that she has type 2 diabetes, she is shocked. Her doctor explains to her that type 2 diabetes can be managed through daily insulin therapy, diet, and exercise. Managed? she thinks, But isn’t there a cure?
To answer that question, some understanding of diabetes as a disease is needed. There are three main forms that diabetes can take: type 1 diabetes, often called juvenile-onset or insulin-dependent diabetes; type 2, also called adult-onset or non-insulin-dependent diabetes; and gestational diabetes, which occurs during pregnancy and may later lead to a diagnosis of type 2 diabetes. What all these diseases have in common is a high level of blood glucose due to abnormalities in insulin action, production, or both.
In type 1 diabetes, the pancreas lacks the ability to produce insulin, a glucose- and fat-storing hormone, due to reasons that are not fully understood. Type 2 diabetes is primarily a disease of insulin resistance, which means that the body produces adequate (or even abnormally high) levels of insulin but cannot utilize it to clear the blood of glucose. If the blood glucose levels remain high for many years, diabetes can cause microvascular (small blood vessel) and macrovascular (large blood vessel) disease throughout the body.
Of the three forms of diabetes, type 2 is by far the most common in the United States; around 90 to 95 percent of diabetics have type 2 disease. The direct cause of type 2 diabetes is currently at the center of controversy in the medical and scientific community, but there is one fact upon which everyone agrees: type 2 diabetes is a lifestyle-related disease, associated with obesity, inactivity, high blood pressure, and high cholesterol and/or triglycerides.
Type 2 Diabetes Is Also Known as Carbohydrate Intolerance
If you have just been told that you have type 2 diabetes, this means that your blood glucose is too high and your insulin is not working to clear the blood of glucose. In other words, you have an “intolerance” to the dietary source of glucose: carbohydrates. This intolerance most often results from being overweight or obese as well as eating in excess foods that contain glucose (sugar and starches). If you have lactose intolerance, you are told to cut down or avoid lactose; if you have carbohydrate intolerance, you should cut down or avoid carbohydrates.
Protein, fat, and fiber in the diet do not raise the blood glucose. High-carbohydrate foods such as potatoes or corn, however, will raise the blood glucose just like table sugar. Foods that contain no or very little carbohydrates, including eggs, meat, cheese, and non-starchy vegetables, do not raise the blood glucose very much or at all. If you have diabetes or a tendency toward diabetes, you can help control your blood sugar by limiting your intake of sugar and starchy carbohydrates and eating foods lower in carbohydrates.
If you are overweight or obese, losing weight will improve your intolerance to carbohydrates. Many people will no longer have elevated blood glucose after losing weight and are able to handle carbohydrates in their diets again. Although the exact mechanism of why the fat tissue causes carbohydrate intolerance is not yet understood, it is known that reduction of fat tissue by weight loss can normalize the carbohydrate intolerance.
A Diet Without Sugar or Starch
The most effective way to reduce your blood glucose through diet is to carefully monitor all the carbohydrates in the foods you eat. Start by checking food labels for the “total carbohydrate count.” Good food choices contain 0 grams (g) or less than 1 g of carbohydrates per serving. Food preparation is less important than carbohydrate count when eating to reduce blood glucose, so meals may be cooked in a microwave oven, baked, boiled, stir-fried, sautéed, roasted, fried (without flour or corn meal), or grilled.
To reduce your blood glucose by diet, add foods like beef (hamburger and steak, for example), pork, ham (unglazed), bacon, lamb, veal, poultry (chicken, turkey, and duck), fish and shellfish, and eggs. To add nutrients like vitamins and fiber, include 2 cups of salad greens and 1 cup of nonstarchy vegetables in daily meals. Salad greens may consist of arugula, celery, Chinese cabbage, chives, cucumber, endive, lettuce (all varieties), parsley, spinach, radicchio, radishes, scallions, or sprouts. Nonstarchy vegetables include artichokes, asparagus, beet greens, bok choy, broccoli, Brussels sprouts, cabbage, cauliflower, chard, Chinese cabbage, collard greens, eggplant, green beans, jicama, kale, leeks, mushrooms, turnip and mustard greens, okra, onions, peppers, pumpkin, shallots, snow peas, spinach, string beans, or sugar-snap peas. You may also add small amounts of the following foods: hard cheese, nuts, olives, avocados, lemon juice, cream, soy sauce, mayonnaise, and pickles.
History of Diabetes Treatment
Before insulin or other medications were available, experts recommended a high-fat, low-carbohydrate diet as the only available treatment for diabetes. When insulin became available in the 1920s, the amount of allowable dietary carbohydrates was increased for practical reasons, and insulin was used to “cover” the dietary carbohydrates. Today many people with diabetes are just told to increase the insulin amount to match the carbohydrates in their diet.
Patients who are now taking insulin and choose to reduce their carbohydrate intake must monitor their blood glucose carefully and be ready to reduce insulin use if needed. In our clinic, for example, we would reduce a patient’s insulin by 50 percent on the first day of changing his or her diet. Then, when the blood glucose comes down below 100 milligrams per deciliter (mg/dL), we reduce insulin again. We have had people on 150 units of insulin per day taper off their insulin in eight days. To avoid low blood glucose, however, we recommend that all patients make these adjustments in consultation with an appropriate doctor.
Although short-term reduction of dietary carbohydrates can be safely accomplished, concerns exist about reducing carbohydrate intake over a longer period. If dietary carbohydrates are reduced, there is a fear that dietary fat may increase, which may in turn increase cardiovascular risk factors. This fear of dietary fat was apparently the reasoning for the low-fat dietary recommendations of the 1970s, which were designed to reduce cardiovascular risk. Without testing, the same philosophy was then applied to diabetes.
The research community has just begun revisiting this idea of reducing dietary carbohydrates as a treatment for type 2 diabetes. In the longest studies of the low-carbohydrate diet to date (one year), reductions in cardiac risk factors were repeatedly seen. Improvements also included weight loss, reduced insulin and triglyceride levels, increased HDL levels (the “good” cholesterol), and reduced blood pressure. Beyond one year, most of what we know about the long-term effects of a low-sugar and low-starch diet comes from the clinical experience of doctors who have used this approach in their practices and the assumption that keeping the blood glucose low is important for reduction in cardiac risk.
Recommended Carbohydrate Intake
Is a reduced-carbohydrate diet for everyone? The Daily Recommended Intake (DRI) for carbohydrate is set at 130 g per day for adults and children based on the average minimum amount of glucose utilized by the brain. Most Americans eat two to three times that much carbohydrates daily. Unfortunately, the carbohydrates that Americans consume that are not utilized for short-term energy needs are stored in the body as fat, which over time may lead to carbohydrate intolerance. A “no sugar or starch diet” may not be appropriate for everyone, but reducing daily carbohydrate intake to, at the very least, DRI levels (130 g per day) in susceptible populations may help prevent the development of type 2 diabetes and obesity. In the largest lifestyle study to date, a controlled-calorie, 50-percent carbohydrate diet halted the development of diabetes in some people, but the disease still progressed in many. (This study diet contained about 300 g of carbohydrates per day!)
Treating Diabetes with Medication
In some cases carbohydrate intolerance in type 2 diabetes is so severe that medications are needed to control the condition. Medication therapies, which include pills or insulin injections, can have their own side effects, however, as some may lead to an increase in hunger and weight gain, which may then lead to more carbohydrate intolerance. Newer medications, such as metformin (Glucophage,® Glucophage XR,® Glumetza,® Fortamet,® and Riomet®) and Byetta® (exenatide), do not seem to cause the weight gain and the hunger seen with insulin but are associated with other side effects.
Unfortunately, studies have shown that even people with type 2 diabetes who are medically “well controlled” can expect their condition to deteriorate over time. Research has found that blood sugar levels over 140 mg/dL (the American Diabetes Association considers good control to be between 130 mg/dL and 180 mg/dL) will begin to damage blood vessels on the micro- and macrovascular levels and create further burnout of beta cells in the pancreas. Normalization of the blood glucose (between 80 mg/dL and 110 mg/dL) with diet therapy and weight loss is thus critical.
Is There a Cure?
Reducing the amount of sugar and starch that you eat can have a powerful effect on lowering your blood sugar. Although there is no “cure” for type 2 diabetes, a reduced-carbohydrate diet, with weight loss if needed, can allow a person with this disease to enjoy a healthy life.
How to Help Control Type 2 Diabetes
In addition to dietary changes and medication options, there is another critical factor that anyone diagnosed with diabetes should consider: exercise. According to the National Diabetes Information Clearinghouse (), research has shown that physical activity can have many positive effects:
- Lower your blood glucose and your blood pressure
- Lower your bad cholesterol and raise your good cholesterol
- Improve your body’s ability to use insulin
- Lower your risk for heart disease and stroke
- Keep your heart and bones strong
- Keep your joints flexible
- Lower your risk of falling
- Help you lose weight
- Reduce your body fat
- Give you more energy
- Reduce your stress level
By discussing exercise options with your healthcare team, you can work together to decide how best to add physical activity into your daily life—including aerobic exercise, strength training, and stretching. It may be that some forms of exercise are not a good idea, so this dialogue with your doctor is important before you start any program. Once you and your doctor have decided on what type of activity is appropriate, you can move ahead with designing an exercise program, finding friends to keep you company and motivate you, and enjoying the benefits of physical activity.
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