Morbid Obesity//Low Carb Diets
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| Tue, 10-14-2003 - 8:53am |
Updated: 06:35 AM EDT
Americans Ballooning to Morbidly Obese Proportions
By LINDSEY TANNER, AP
CHICAGO (Oct. 13) - Americans are not just getting fatter, they are ballooning to extremely obese proportions at an alarming rate.
The number of extremely obese American adults - those who are at least 100 pounds overweight - has quadrupled since the 1980s to about 4 million. That works out to about 1 in every 50 adults.
Extreme obesity once was thought to be a rare, distinct condition whose prevalence remained relatively steady over time. The new study contradicts that thinking and suggests that it is at least partly due to the same kinds of behavior - overeating and under-activity - that have contributed to the epidemic number of Americans with less severe weight problems.
In fact, the findings by a RAND Corp. researcher show that the number of extremely obese adults has surged twice as fast as the number of less severely obese adults.
On the scale of obesity, "as the whole population shifts to the right, the extreme categories grow the fastest," said RAND economist Roland Sturm. He added: "These people have the highest health care costs."
Sturm said health problems associated with obesity - including diabetes, heart disease, high blood pressure and arthritis - probably affect the extremely obese disproportionately and at young ages.
Sturm analyzed annual telephone surveys conducted nationwide by the Centers for Disease Control and Prevention. His report covers surveys from 1986 through 2000. The findings appear in Monday's Archives of Internal Medicine.
In 1986, 1 in 200 adults reported height and weight measurements reflecting extreme obesity, or a body-mass index of at least 40. By 2000 that had jumped to 1 in 50, Sturm found.
The prevalence of the most extreme obesity - people with a BMI of at least 50 - grew fivefold from 1 in 2,000 to 1 in 400, Sturm said.
By contrast, ordinary obesity - a BMI of 30 to 35 - doubled, from about 1 in 10 to 1 in 5, based on the same surveys.
Americans tend to understate their weight, and a recent study based on actual measurements found an obesity rate of nearly 1 in 3, or almost 59 million people. Sturm said his findings probably understate the problem for the same reason.
The average man with a BMI of 40 in Sturm's study was 5-foot-10 and 300 pounds, while the average woman was 5-foot-4 and 250 pounds.
Dr. Mary Vernon, a trustee of the American Society of Bariatric Physicians, said the study reflects what doctors who specialize in treating obesity are seeing in their offices. Vernon said the number of her patients weighing 300 to 350 pounds or so has doubled in the past several years.
She said thinking has evolved from a generation ago, when many doctors believed extreme obesity was due to hormonal abnormalities or other distinct conditions.
Now many believe it is a combination of lifestyle factors and genetics, as well as a propensity for some people's bodies to be hyper-efficient at storing calories. This tendency would benefit people in societies where starvation is rampant but is a huge problem in developed countries where food is plentiful and lifestyles are increasingly sedentary, Vernon said.
Vernon said the biggest challenge in treating severely obese people, who typically have tried mightily to lose weight, "is giving them enough hope that it's worth trying again."
10/13/03 16:35 EDT
See also the latest on Low Carb Diets:
Low-Carb Diets Are Working, Study Says
By DANIEL Q. HANEY, AP
FORT LAUDERDALE, Fla. (Oct. 13) - The dietary establishment has long argued it's impossible, but a new study offers intriguing evidence for the idea that people on low-carbohydrate diets can actually eat more than folks on standard lowfat plans and still lose weight.
Perhaps no idea is more controversial in the diet world than the contention - long espoused by the late Dr. Robert Atkins - that people on low-carbohydrate diets can consume more calories without paying a price on the scales.
Over the past year, several small studies have shown, to many experts' surprise, that the Atkins approach actually does work better, at least in the short run. Dieters lose more than those on a standard American Heart Association plan without driving up their cholesterol levels, as many feared would happen.
Skeptics contend, however, that these dieters simply must be eating less. Maybe the low-carb diets are more satisfying, so they do not get so hungry. Or perhaps the food choices are just so limited that low-carb dieters are too bored to eat a lot.
Now, a small but carefully controlled study offers a strong hint that maybe Atkins was right: People on low-carb, high-fat diets actually can eat more.
The study, directed by Penelope Greene of the Harvard School of Public Health and presented at a meeting here this week of the American Association for the Study of Obesity, found that people eating an extra 300 calories a day on a very low-carb regimen lost just as much during a 12-week study as those on a standard lowfat diet.
Over the course of the study, they consumed an extra 25,000 calories. That should have added up to about seven pounds. But for some reason, it did not.
"There does indeed seem to be something about a low-carb diet that says you can eat more calories and lose a similar amount of weight," Greene said.
That strikes at one of the most revered beliefs in nutrition: A calorie is a calorie is a calorie. It does not matter whether they come from bacon or mashed potatoes; they all go on the waistline in just the same way.
Not even Greene says this settles the case, but some at the meeting found her report fascinating.
"A lot of our assumptions about a calorie is a calorie are being challenged," said Marlene Schwartz of Yale. "As scientists, we need to be open-minded."
Others, though, found the data hard to swallow.
"It doesn't make sense, does it?" said Barbara Rolls of Pennsylvania State University. "It violates the laws of thermodynamics. No one has ever found any miraculous metabolic effects."
In the study, 21 overweight volunteers were divided into three categories: Two groups were randomly assigned to either lowfat or low-carb diets with 1,500 calories for women and 1,800 for men; a third group was also low-carb but got an extra 300 calories a day.
The study was unique because all the food was prepared at an upscale Italian restaurant in Cambridge, Mass., so researchers knew exactly what they ate. Most earlier studies simply sent people home with diet plans to follow as best they could.
Each afternoon, the volunteers picked up that evening's dinner, a bedtime snack and the next day's breakfast and lunch. Instead of lots of red meat and saturated fat, which many find disturbing about low-carb diets, these people ate mostly fish, chicken, salads, vegetables and unsaturated oils.
"This is not what people think of when they think about an Atkins diet," Greene said. Nevertheless, the Atkins organization agreed to pay for the research, though it had no input into the study's design, conduct or analysis.
Everyone's food looked similar but was cooked to different recipes. The low-carb meals were 5 percent carbohydrate, 15 percent protein and 65 percent fat. The rest got 55 percent carbohydrate, 15 percent protein and 30 percent fat.
In the end, everyone lost weight. Those on the lower-cal, low-carb regimen took off 23 pounds, while people who got the same calories on the lowfat approach lost 17 pounds. The big surprise, though, was that volunteers getting the extra 300 calories a day of low-carb food lost 20 pounds.
"It's very intriguing, but it raises more questions than it answers," said Gary Foster of the University of Pennsylvania. "There is lots of data to suggest this shouldn't be true."
Greene said she can only guess why the people getting the extra calories did so well. Maybe they burned up more calories digesting their food.
Dr. Samuel Klein of Washington University, the obesity organization's president, called the results "hard to believe" and said perhaps the people eating more calories also got more exercise or they were less apt to cheat because they were less hungry.
10/13/03 15:30 EDT
