March 16 (UPI) -- A massive study in Europe is challenging the so-called "obesity paradox" in which overweight or obese people are not at increased risk of heart disease.
This latest research of 296,535 adults of white European descent between 2006 and 2010 shows that the risk of heart attacks, strokes and high blood pressure increase as body mass index increases beyond 22-23 kg/m.
The new study, published Friday in the European Heart Journal, concludes that the risk of people with an ideal BMI had the lowest risk of cardiovascular disease. Risk increased, however, by 13 percent for every 5.2 BMI increase in women and 4.3 BMI increase in men.
The risk for cardiovascular disease also grew as a person's waistline did the same.
In women with a waist of 29.1 inches and men with 32.6 inches, the risk increases by 16 percent in woman for every 5 inches and 10 percent in men for every 4.5 inches.
"Any public misconception of a potential 'protective' effect of fat on heart and stroke risks should be challenged," Dr. Stamatina Iliodromiti, a clinical lecturer in obstetrics and gynecology at University of Glasgow, said in a press release.
The "obesity paradox" is based on previous research that has suggested that being overweight or even obese, particularly in the elderly, might not have an effect on deaths from heart disease. If people maintain a reasonable level of fitness, the theory posits, the extra weight might be protective
Iliodromiti disagrees, based on the new study of data from the U.K. Biobank on 171,285 women and 125,250 men between the ages of 40 and 69.
"This is the largest study that provides evidence against the obesity paradox in healthy people," Iliodromiti said. "It is possible that the story may be different for those with pre-existing disease because there is evidence that in cancer patients, for instance, being slightly overweight is associated with lower risk, especially as cancer and its treatments can lead to unhealthy weight loss."
"By maintaining a healthy BMI of around 22-23, healthy people can minimize their risk of developing or dying from heart disease. In terms of other adiposity measures, the less fat, especially around their abdomen, they have, the lower the risk of future heart disease."
The researchers noted that the "obesity paradox" might have been influenced by other factors, including smoking changes the distribution of fat in the body and people with undiagnosed disease have lower weight.
The researchers noted that it can be difficult for people to reach the ideal BMI.
"We know many cannot get to such low BMIs so the message is, whatever your BMI, especially when in the overweight or obese range, losing a few kilograms or more if possible, will only improve your health," said Naveed Sattar, a professor of metabolic medicine at the University of Glasgow. "There are no downsides to losing weight intentionally and the health professions needs to get better at helping people lose weight."
A study published earlier this month by Northwestern University researchers refutes the "obesity paradox" as well.
Among participants 40 to 50 years old and of varying weights, researchers found that the risk for the various cardiovascular conditions was 21 percent higher in overweight men and 67 percent higher in obese men compared with normal-weight men.