Blood Sugar and Brain Fitness

A recent study provides a clue into the exercise-brain fitness relation. A paper reported in the December 2008 issue of the journal Neurology shows that high levels of blood glucose (the kind that can happen in people with diabetes) may directly affect the hippocampus. Since the hippocampus is a part of the brain that is essential for memory, this study helps us understand one way in which physical fitness can affect brain function. What’s the link? We know that physical fitness improves the body’s ability to regulate blood sugar levels, so being physically fit may decrease the damage that high blood sugar levels can cause to the hippocampus.

The story is a little more complicated, though (isn’t it always)? Blood sugar is regulated by a hormone called insulin. People who have type II diabetes (the kind that people usually get later in life) have a condition called insulin resistance. This means that the body makes enough, and sometimes too much, insulin. The problem is that the insulin doesn’t have a strong enough effect. This means that the body keeps making higher levels of insulin. Exposing the body to high levels of insulin can cause problems.

In the case of the brain, insulin is very important for its function. Insulin has to cross into the brain from the blood by way of a special mechanism called a transporter protein. When insulin levels are high all the time, the body decreases the number of these transporter proteins, and the brain may not get enough insulin. Some studies have shown that insulin is important in memory function, so a decrease in the number of these transporter proteins may be yet another way that high blood sugar levels can affect memory. While all of these studies are preliminary, they add to what we know about high blood sugar, insulin resistance, and mental functioning.

There are two effective ways of keeping your blood sugar under control: diet and exercise. Following the Mediterranean diet can help, because it emphasizes the kinds of food that will help keep your blood sugar stable. Exercise has been shown to help your body be more sensitive to the effects of insulin. When your body is more sensitive to insulin’s effects, blood sugar levels will be lower and more stable. We know that following the Mediterranean diet and regular exercise can help your memory – their link to blood sugar and blood sugar’s effects on the brain may be why.

Book Review: The Miami Mediterranean Diet

The Mediterranean diet is an important part of any brain health program. A number of studies have shown that people who follow the Mediterranean diet have less chance of having a heart attack, and that changing to the diet can reduce risk for another heart attack. Consistent with our increasing appreciation of the relation of heart and brain risk factors, at least one study has shown that people who follow the Mediterranean diet more closely have a lower risk of being diagnosed with Alzheimer’s disease.

Just that may be enough to have you ready to try the diet, but you might wonder what it is and what you’re supposed to eat. That’s where Dr. Michael Ozner’s book comes in. Dr. Ozner is a cardiologist in Miami, Florida, and says that he has been using the diet to treat his patients for more than 25 years. The book includes clinical vignettes in which patients describe their experiences with the diet and how it has helped them. Although Dr. Ozner recommends the often-unpopular practice of counting calories, people who follow the diet may find that they can eat more and still lose weight because of the diet’s emphasis on low-glycemic index foods, fresh fruit and vegetables, and whole-grain breads and pastas.

In clear language Dr. Ozner lays out the reasons why you should be interested in the diet. He gives you an overview of the studies that have shown that people who follow the diet have lower risk for heart disease, and explains why. You may note that many of the elements of the Mediterranean diet have anti-inflammatory and anti-oxidant effects, making it similar in this respect to Dr. Andrew Weil’s anti-inflammatory diet.

But the book has lots more than just a description of the why the diet is important. It also has a complete 14-day diet plan and a wide selection of recipes that any cook can use to make the diet not just healthy but delicious. My favorite section of recipes is the one for pizzas. There is also a section with a number of recipes for desserts that are high in flavor and low in fat.

Overall, this is a very useful book that will help you understand the importance of the Mediterranean diet and will help you get started in following it.

The Miami Mediterranean Diet: Lose Weight and Lower Your Risk of Heart Disease with 300 Delicious Recipes

Hardcover, 432 pages, ISBN 978-1933771502, $25.95.

Click here to order the book from Amazon.