Recent news reports on a recently published study appear to be suggesting that being ‘apple-shaped’, where you carry fat around your waist and middle, does not put you at greater risk of heart attack and other cardiovascular problems, which is contrary to previous research. But a closer look at the study itself reveals that the newspapers may not be reporting the full story of the findings.
Last month, a new paper published in the medical journal The Lancet reviewed 58 studies which looked at cardiovascular disease outcomes which included heart attacks, strokes and deaths related to coronary artery disease or stroke. The researchers took into account the individual records of over 220,000 people from these studies to look at the relationship between the risk of these cardiovascular disease outcomes and the 3 measurements of fat — BMI, waist circumference and waist-to-hip ratio.
They found that for every one standard deviation rise in BMI, waist circumference and waist-to-hip ratio, the associated increase in any cardiovascular disease outcome was 7%, 10% and 12% respectively. These figures mean that all three measures of body fat are independently associated with an increased cardiovascular risk.
But after taking into account other factors that can affect heart disease risk — such as blood pressure, age, and cholesterol levels — the researchers concluded that none of these fat measures, whether on its own or in combination, can improve predictions that are made from the data about these other risk factors.
Commenting on the study, Dr Christine Bennett, Chief Medical Officer of Bupa Australia said: “This study is interesting because it explores obesity as a risk factor of cardiovascular disease, and the findings do not challenge current recommendations that reaching and maintaining a healthy weight is good for heart health.
“While the study does not find one fat measurement to be statistically better than another at predicting the risk of a cardiovascular event, it does confirm that obesity is bad for the heart, no matter where the fat is and how it’s measured. It’s important for people to be aware of that obesity remains a risk for heart disease. It’s long been known that conditions such as high blood pressure, high cholesterol and diabetes contribute to the development of heart disease. Being overweight or obese increases your risk of having these conditions and the harmful effects of being overweight or obese are then borne out through those other established risk factors for heart disease and stroke.
“The relationship between body shape, weight and health is a complex one, often complicated by lifestyle habits and long-term conditions. However, by maintaining a healthy weight through healthy eating and regular physical activity, you are taking one important step toward wellness. Other steps toward better health include not smoking and maintaining good blood pressure and cholesterol levels, which can help to reduce your likelihood of developing a number of long-term health problems.”
The Emerging Risk Factors Collaboration. Separate and combined associations of body-mass index and abdominal adiposity with cardiovascular disease: collaborative analysis of 58 prospective studies.
The Lancet, Early Online Publication, 11 March 2011. doi:10.1016/S0140-6736(11)60105-0