40% of cancers diagnosed in U.S. related to obesity, CDC says

The rates of 12 obesity-relatedcancers rose by 7 per cent from 2005 to 2014, an increase that isthreatening to reverse progress in reducing the rate of cancerin the United States, U.S. health officials say.

According to the U.S. Centers for Disease Control andPrevention, more than 630,000 people in the United States werediagnosed with a cancer linked with being overweight or obese in2014.

Obesity-related cancers accounted for about 40 per cent ofall cancers diagnosed in the United States in 2014. Although theoverall rate of new cancer diagnoses has fallen since the 1990s, rates of obesity-related cancers have been rising.

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"Today's report shows in some cancers we're going in thewrong direction," Dr. Anne Schuchat of the CDC said on aconference call with reporters.

According to the International Agency for Research onCancer, 13 cancers are associated with overweight and obesity.
They include:

• Meningioma.
• Multiple myeloma.
• Adenocarcinoma of theesophagus.
• Cancers of the thyroid, postmenopausal breast,gallbladder, stomach, liver, pancreas, kidney, ovaries, uterusand colon and rectum (colorectal).

In 2013-2014, about two out of three U.S. adults wereconsidered overweight or obese. CDC researchers used the U.S.cancer statistics database to see how obesity was affectingcancer rates. Although cancer rates rose in 12 of these cancersfrom 2005 to 2012, colorectal cancer rates fell by 23 per cent,helped by increases in screening, which prevents new cases byfinding growths before they turn into cancer.

Cancers not associated with overweight and obesity fell by13 per cent.

About half of Americans are not aware of this link,according to Schuchat. The findings suggest that U.S. healthcareproviders need to make clear to patients the link betweenobesity and cancer, and encourage patients to achieve a healthyweight.

"The trends we are reporting today are concerning," Schuchatsaid. "There are many good reasons to strive for a healthyweight. Now you can add cancer to the list."

She said the science linking cancer to obesity is stillevolving, and it is not yet clear whether losing weight willhelp individuals once cancer has taken root.

What is clear is that obesity can raise an individual's riskof cancer, and that risk may be reduced by maintaining a healthyweight, Schuchat said Tuesday.