Lesson 20: Weight Management (page 1 of 4)


Dieting, Weight Loss and Lifetime Weight Management

A study published in the Journal of the American Medical Association (JAMA; 10.17.99) shows that Americans are fatter than ever and are getting fatter at an alarming rate. This eight-year study, conducted by the Centers for Disease Control and Prevention, reports that one in five American adults is now obese. This is a drastic increase from just 10 years ago when one in eight Americans were obese. This development has prompted the Centers for Disease Control to classify obesity in the U.S. as an epidemic.

Being overweight increases risks for a number of serious health problems including heart disease and stroke, diabetes, cancer, sleep apnea, osteoarthritis and gallbladder disease. Heart disease, diabetes and cancer are the three biggest killers of American men and women, so the problem is not just a cosmetic one!

According to the JAMA study, 300,000 deaths in the United States each year can be attributed to being overweight. Compare this to the 430,000 deaths each year caused by smoking and you will see that—with the exception of quitting smoking—there is probably no single preventative measure that can guarantee your health more than maintaining your ideal weight.

What is Obesity?

The difference between obesity and simply being overweight is a matter of degree. Although being even slightly or moderately overweight can and does increase certain health risks, it is usually not considered a serious medical problem. Obesity, on the other hand, is considered a serious condition that, if not properly managed, is likely to lead to serious health problems, and possibly death.

The medical criteria for obesity is determined by a formula called the Body Mass Index (BMI), defined as your weight in kilograms divided by your height in meters squared (BMI = kg/m2). A BMI of 19 to 24.9 is considered a “normal” weight. A BMI of 25 to 29.9 is considered overweight and 30 or above is considered obese. The Body Mass Index is not perfect. Muscular individuals, especially those who are short in stature, will have a tendency to score higher than they should. We also normally tend to exchange muscle weight for fat as we get older. (See chart adjusting for age below.) But for most individuals the BMI is a very good indicator of where we are in relation to where we should be.

Below is the official classification of the Body Mass Index from the WHO
Normal weight
Over weight
Obesity I
Obesity II
Obesity III
Below are the values for normal BMI adjusted for age

First Rule: Don’t Diet!

If you are overweight, most likely you have discovered that starvation diets are not the answer. Most any diet will result in short-term weight loss, but it is rare for a diet to help in the long run. Diets that restrict caloric intake are a common cause of underactive thyroid. There is a slowing of the body’s metabolism as the thyroid gland learns to expend energy more efficiently to conserve calories for the next “famine.” After a starvation diet we will have a tendency to gain even more weight than we took off, and we will find it even more difficult to lose weight the next time we try. A low-calorie diet can suppress the thyroid function in less than 24 hours. After one to three months of such dieting, there is a danger of permanently inhibiting the thyroid function. The first rule in sensible weight control is therefore, no starvation diets!

Starvation diets are self-defeating because they can slow the body’s metabolism by suppressing the ________ gland.


(Select the best answer and click on the “Continue” button.)