Ask Dr. K: Weight loss, healthy diet are best medicine for diabetics

You can reduce or eliminate multiple medications even if you’ve been taking them for a long time. The secret: You must lose weight and make a lifelong commitment to a healthy diet and regular exercise. That’s not a surprise. An unhealthy diet, lack of regular exercise and weight gain all play a big role in causing Type 2 diabetes in the first place.

People with Type 2 diabetes have elevated levels of blood sugar, or glucose. That’s because glucose cannot get from the blood into cells, which need it for energy. It takes a key to open the door to your cells and let in the sugar that’s in the blood. This key is the hormone insulin. In Type 2 diabetes, insulin can’t effectively open the cell doors. This is known as insulin resistance.

Your pancreas initially tries to overcome insulin resistance by producing more insulin. This leads to a vicious cycle of continually rising insulin levels, greater insulin resistance and more insulin production. Eventually, the pancreas cannot keep up with the demand for more insulin. You wind up with a “pooped pancreas.” That’s when your blood sugar starts to rise.

Losing weight can reverse the course of Type 2 diabetes. It does so by making your cells more sensitive to insulin. Weight loss can also help prevent long-term diabetes-related health problems. These include heart disease and damage to the nerves, kidneys and eyes.

How does losing weight help make your cells more sensitive to insulin and thereby lower your blood sugar levels? One theory is that your fat cells make a hormone that then travels in the blood and causes cells to resist the effect of insulin. The fatter your fat cells get, the more of this hormone is produced. One candidate hormone called “resistin” has been discovered, and its role in causing insulin resistance is being studied.

Regular exercise promotes weight loss by burning calories. Even if regular exercise does not cause you to lose weight, it decreases your insulin resistance. Recently, another hormone called “irisin” was discovered here at Harvard Medical School. When you exercise, your muscles make more of this hormone. As a result, you burn more fat.

In their instructive new book, “The Diabetes Breakthrough,” my colleague Dr. Osama Hamdy, medical director at Harvard Medical School-affiliated Joslin Diabetes Center, and Sheri Colberg lay out a specific program of weight loss through diet and exercise to help you reverse Type 2 diabetes and reduce or even discontinue your diabetes medications. You can learn more about this book on my website, AskDoctorK.com.

Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.