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The good news about belly fat is that it tends to be some of the first fat to go when people lose weight. The bad news is that it tends to return quickly if they put the weight back on.
The good news about belly fat is that it tends to be some of the first fat to go when people lose weight. The bad news is that it tends to return quickly if they put the weight back on. Cameron Spencer/Getty Images
At The New England Journal of Medicine's Web site:
Courtesy Harvard Medical School
While subcutaneous fat sits in storage waiting to be burned for energy, abdominal fat cells are much more metabolically and biologically active. Researchers say this can make them more problematic to a person's health.
If you've been waiting for one more reason to finally get rid of that excess belly fat, take note. Researchers in Germany have found that fat accumulated in the abdomen can be far more dangerous to your health than fat on other parts of the body.
Their study, which appears in this week's New England Journal of Medicine, found that excess weight around the abdomen nearly doubled a person's risk of death from a variety of diseases, including cancer, stroke and heart disease. A large waist circumference, researchers found, was even more indicative of health risks than body mass index (BMI), the traditional measure for obesity.
The results of the study, which involved nearly 360,000 participants from nine European countries, add to a long line of research that shows abdominal fat is harmful.
Harvard University endocrinologist Dr. JoAnn Manson, who is also chief of preventive medicine at Boston's Brigham and Women's Hospital, says researchers now understand that abdominal fat is different than fat on other parts of the body.
"In particular, deep abdominal fat is by far the most dangerous fat in terms of risk of diabetes, heart disease and stroke," Manson says. "Most of the research studies suggest that this abdominal fat at least triples the risk of cardiovascular disease, diabetes, hypertension and abnormal cholesterol levels."
Why is belly fat so much worse than other types of fat? In part, because it functions differently. The fat that collects on a person's thighs, buttocks and upper arms — known as subcutaneous fat — is right under the skin and can be easily grabbed. But abdominal fat — known as visceral fat — is out of reach, stuck deep within the abdominal cavity, between abdominal organs.
While subcutaneous fat sits in storage waiting to be burned for energy, abdominal fat cells are much more metabolically and biologically active, Manson says.
"They tend to be more active in producing hormones and chemical messengers that cause inflammation throughout the body," she notes.
The location of this fat is part of what makes it so problematic. The hormones and chemicals produced by abdominal fat can affect nearby organs, particularly the liver.
"This fat drains directly to the liver, and it's associated with increased fat within the liver, which is also a risk factor for insulin resistance," she says. This sets the stage for Type 2 diabetes.
Dr. Robert Kushner of Northwestern University's School of Medicine, who specializes in the care of overweight and obese patients, says abdominal fat also is dangerous for the heart.
"This abdominal fat releases fatty acids and other signals that go to the rest of the body and cause increased blood fats like cholesterol and triglycerides, as well as higher blood pressure," Kushner says.
Scientists don't know why belly fat acts so differently than other fat, but there are theories. One has to do with evolution. It suggests that deep abdominal fat developed from embryonic fat, and that embryonic fat had to be especially flexible and active to enable healthy fetal development.
While researchers may not know all the why's of abdominal fat, they do know what a person can do about it. The first step is to find out if you're at risk. Measure your waist: The threshold for increased risk in women is 35 inches and for men, it's 40 inches. If your waist is larger than that, Kushner says you should lose weight.
"What I can tell you is that you cannot spot-reduce your belly fat. So doing more calisthenics or sit-ups can strengthen muscles in the abdominal core, but you're not going to mobilize more fat from the belly area," he says. "You have to go back to the old 'tried and true': Reduce the amount of total calories you consume, and burn off more calories over the course of a day."
Exercise, of course, is what helps burn excess calories. Experts think you need at least 60 minutes of exercise a day to lose weight. But Manson says the good news is that "this [tummy] fat is often the first to go with weight loss, which may explain why even most weight loss of 5 to 10 percent of body weight can be very helpful in terms of improving blood sugar, blood pressure, cholesterol and overall improvements in metabolism."
The bad news, Manson adds, is that "this abdominal fat is often the first fat to come back when we gain weight."
What breaks down easily, she explains, tends to return easily.