Despite all the obesity studies and news reports on how unhealthy eating and inactivity are recipes for chronic disease or worse, a new survey finds Americans aren't getting the entire message.
The survey found that many Americans know about heart disease and diabetes as major health risks from obesity, but few realize other conditions including cancer, arthritis, sleep apnea and infertility are tied to having excess weight.
Only about one-quarter of people think it's possible for someone to be very overweight and still healthy, according to the poll by The Associated Press-NORC Center for Public Affairs Research.
When asked about the most serious consequences, more than 7 in 10 Americans can correctly tick off heart disease and diabetes. Heart disease is the nation's leading killer, and diabetes and obesity are twin epidemics, as rates of both have climbed in recent years.
The other consequences aren't so well known, the survey revealed.
"People are often shocked to hear how far-reaching the effects of obesity are," said Jennifer Dimitriou, a bariatric dietitian at New York's Montefiore Medical Center.
Only 7 percent of people surveyed mentioned cancer, although doctors long have known that fat increases the risk of developing certain types of cancers. A March study meanwhile found upticks in cancers of the esophagus, uterus, pancreas and kidney despite overall declines in cancer rates. Experts at the time said excess weight triggers production of hormones that can play a role in cancer growth.
Being overweight can also make it harder to spot tumors early and to treat them.
Then there's the toll on your joints, especially the knees. About 15 percent of people knew obesity can contribute to arthritis, a vicious cycle as the joint pain then makes it harder to exercise and shed pounds.
Recent research shows rates of knee replacement surgeries have nearly doubled for patients 65 and older over the past 20 years, driven in part by increasing obesity rates.
High blood pressure, high cholesterol and strokes were also fairly low on the survey list. Infertility didn't get a mention.
Also, 5 percent put respiratory problems on the list. Studies show people who are overweight are at increased risk of sleep apnea and asthma, and that dropping pounds can help improve their symptoms.
Knowing more about the myriad ways obesity affects health could help motivate people to get more active and eat better before full-blown disease strikes, Dimitriou said.
"Most people want to become healthier. It's the know-how, and understanding what the consequences are," she said.
But only 52 percent of those surveyed said they've discussed the health risks of being overweight with a doctor.
In another complication, the AP-NORC Center survey found that about half of people think their weight is just about right, and only 12 percent of parents think their child is overweight. That's even though government figures show two-thirds of U.S. adults, and one-third of children and teens, are either overweight or obese.
If you're surrounded by overweight people, especially in your family, "then that's all you know, and that to you is normal," Dimitriou said.
The AP-NORC Center survey was conducted Nov. 21 through Dec. 14. It involved landline and cell phone interviews with 1,011 adults nationwide and has a margin of sampling error of plus or minus 4.2 percentage points.
Despite the health problems associated with obesity, another survey by AP-NORC released last week raised questions about how people want these issues addressed.
That survey found while most people support nutrition guidelines to help Americans make better choices along with the posting of calorie counts on restaurant menus, nearly six in ten of those surveyed opposed unhealthy food taxes and three-quarters of respondents were against government restrictions on what people can purchase.
The CDC has more information on obesity's health consequences.
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