What Do You Mean, I'm Obese?

If you think you need to lose a few pounds, join the club. According to federal guidelines, more than half of all adult Americans are members.

The National Institutes of Health (NIH) puts the definition of overweight as  a body mass index (BMI) of 25 to 29 The BMI is a ratio of weight to height.  A BMI of 30 or greater qualifies a person as obese. A person with a BMI of 30 is about 30 pounds overweight, the equivalent of 221 pounds for a person who is 6 feet tall, or 186 pounds for someone who is 5-foot-6.

Even for those who don't need to lose weight, BMI is still important. The NIH urges all adults to determine their BMI, and, if normal, reassess their BMI every two years.

Why all the fuss about BMI?

As your BMI goes up, so does your risk for health problems, the NIH says. Your blood pressure goes up and so do your cholesterol levels. Obese men are more than twice as likely to have high blood pressure, high blood cholesterol, or both, compared with men who are of normal weight. Women who are obese are four times as likely to have either or both of those conditions, according to the NIH. People who are overweight or obese in midlife may have an increased risk for dementia in later life. According to a study published in April 2005 in the British Medical Journal, people who were obese in their 40s were 75 percent more likely to develop dementia; for people who were overweight in their 40s, the likelihood was 35 percent.

And the list goes on: Cardiovascular disease, stroke, sleep apnea, osteoarthritis and even certain cancers are more likely with more weight. Experts tally the cost of treating obesity-related diseases at $100 billion a year.

Diabetes also increases with increased weight. Cases of type 2 diabetes are rising rapidly in the United States and appearing at younger ages, chiefly because of a rise in the number of overweight Americans.

But although BMI is useful in predicting health problems, it doesn't give the entire picture. A muscular person might have a BMI in the danger zone, but that person wouldn't necessarily be at increased risk.

So, doctors look at a patient's waist circumference and risk factors for diseases linked to obesity before advising the patient to lose weight. A waist circumference of 40 inches and over in men and 35 inches and over in women increases the risk of health problems, if the BMI is also in the overweight or obese category.

After you know your BMI, then what?

Unfortunately, nutrition experts say, if your BMI is higher than it should be, there's no instant cure. You still need to eat less and exercise more. The U.S. Department of Agriculture's 2005 guidelines for nutrition and exercise recommend 30 to 60 minutes of moderate to vigorous exercise most days of the week to help maintain a stable weight.  Sixty to 90 minutes of vigorous exercise daily will help sustain weight loss.

Even if you get plenty of exercise, you still need to watch your calories. You should follow a balanced diet, with 20 to 35 percent of your calories coming from fat, 45 to 65 percent coming from complex carbohydrates and the remainder from protein. Eat slowly and just until you are full, not stuffed

The NIH and other experts blame the growing heft of Americans on our love affair with food, as well as on our couch potato lives. Where we used to have one car per family, we now drive two or three. We change TV channels by remote control. We steer riding lawnmowers around our yards.

And food is much more available than it ever was, with restaurants and delis in every shopping center and fast food available in many high schools. Super-sized meals remain available in some fast-food restaurants. An additional attraction in many fast-food places is the “dollar menu,” typically high-calorie, high-fat foods such as a double cheeseburger available for only $1.

Changing your lifestyle is the difficult part. It's important to realize that a quick fix isn't available. To lose weight and keep it off takes a commitment to healthier eating and regular exercise.