Dear Doctors: When I had my annual checkup last fall, the blood test showed I am close to having prediabetes. My doctor said I need to change my diet and get more exercise. I recently read that taking a walk right after eating helps lower blood sugar. Do you know if that's true?
Dear Reader: Blood sugar control is crucial to maintaining good health. Over time, high blood sugar levels can lead to a wide range of serious health problems. These include damage to the nerves, heart, kidneys, eyes, and the large and small blood vessels.
Prediabetes means that blood sugar levels are elevated beyond the normal range, but are not yet high enough to qualify as Type 2 diabetes. However, someone with prediabetes is at increased risk of developing Type 2 diabetes. Having Type 2 diabetes raises your chances of developing heart, eye or kidney disease, and having foot problems. It also increases risk of a heart attack or stroke.
The good news is that, as your doctor has advised, a healthy diet and regular exercise can reverse prediabetes. That begins with limiting sugar and other simple carbs and avoiding highly processed foods. At the same time, you want to incorporate 25 to 30 grams of fiber per day, preferably from vegetables, fruit, leafy greens and whole grains.
Exercise is also important. When muscles are active, two things occur. They increase their demand for glucose dissolved in the blood. They also become more sensitive to the effects of insulin, the hormone that helps move glucose from the blood and into the muscles to be used as energy.
When it comes to exercise, a group of researchers recently uncovered surprising news. They selected seven studies that looked at how sitting, standing and walking affect the body. In five of the studies, the participants had normal blood sugar. In two, they had either prediabetes or Type 2 diabetes. Among the metrics the researchers examined were changes in blood levels of glucose and insulin.
The data showed that even a five-minute walk after eating a meal had a measurable effect on moderating blood sugar levels. The beneficial effect of walking was observed during a 60- to 90-minute window following the meal. For people who took a walk during that time, changes to blood sugar were not only less extreme, but also occurred more gradually. That's important because sudden blood sugar spikes and drops can raise cardiovascular risk and are believed to play a role in developing Type 2 diabetes.
This positive effect on blood sugar occurred in all the participants who took a post-meal walk, regardless of their diabetes status. Standing after eating also had a beneficial effect, but it was far more modest.
You are fortunate that your annual physical provided a warning about your Type 2 diabetes risk. Prediabetes is a silent condition, which means it produces no symptoms. It is important that you follow through with changes to diet and increased exercise. And as research suggests, even short walks after eating can help improve blood sugar control.
(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)
