News Analysis |
Some people with obesity are free of metabolic diseases such as diabetes, which is often found to accompany this condition. It is known as “metabolically healthy obesity.” But a new study on women suggests that the “healthy” attribute should be taken with a considerably large pinch of salt.
Can any type of obesity ever be characterized as ‘healthy’? A new study suggests that the answer might be ‘no.’ Obesity tends to bring with it numerous health risks, including type-2 diabetes, hypertension, and several types of cancer. According to the National Institute of Diabetes and Digestive and Kidney Diseases, in the years 2013 and 2014, up to 40.4 percent of adult women in the United States had been diagnosed with obesity.
However, WHO defines ‘health’ as “a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity”.
Still, some women have what is often known as “metabolically healthy obesity,” as, despite their high body mass index (BMI), they do not have many of the additional health conditions that obesity is a major risk factor for.
But as specialists have pointed out, there is currently no clear definition of metabolically healthy obesity, so different studies investigating the specifics of this condition may each describe it differently. Research published recently in The Lancet Diabetes & Endocrinology opts for a definition that characterizes it as obesity in the “simultaneous absence of hypertension, dyslipidemia, and diabetes.”
The authors of this study, however, were interested in addressing a question that is a frequent point of debate when considering metabolically healthy obesity: “Does it affect the risk of cardiovascular disease (CVD), and if so, to what extent?”
Lead researcher, Prof. Matthias Schulze — from the German Institute of Human Nutrition Potsdam-Rehbruecke in Nuthetal — and colleagues hypothesized that while at first glance, obesity free of metabolic diseases may not heighten a person’s risk of CVD, in the long-term, it may lead to the same negative effects on cardiovascular health as other types of obesity.
Is metabolically healthy obesity ‘healthy?’
At first, the research team identified previous studies that had looked at the effects of metabolically healthy obesity on health, focusing on those that followed up the participants over a long period of time (over 12 years). A systematic review of these studies revealed that obesity — whether or not it is accompanied by metabolic diseases — heightens the risk for cardiovascular conditions.
According to the National Institute of Diabetes and Digestive and Kidney Diseases, in the years 2013 and 2014, up to 40.4 percent of adult women in the United States had been diagnosed with obesity.
To confirm these preliminary observations, Prof. Schulze and team went ahead and conducted a large cohort study involving 90,257 women — recruited using the ongoing Nurses’ Health Study — who were free of CVD at baseline. The participants were then split into different health categories based on their BMIs, their baseline metabolic health status and change in metabolic health status.
Then, they were followed up for a period of 30 years (1980–2010). In order to monitor any changes in health, the women were sent questionnaires every couple of years, so they were able to report any relevant medical information.
Over an average follow-up period of 24 years, 6,306 women were diagnosed with CVD, and the researchers also recorded 3,304 heart attacks, as well as the occurrence of 3,080 strokes. For their analysis, the researchers also adjusted for influencing factors, including the participants’ age, levels of physical activity, smoking and drinking habits, ethnicity, aspirin use, and any family history of heart attack or diabetes.
Whether metabolically healthy patients are actually healthy or not, is still under debate; along with a standard definition of this condition. However, WHO defines ‘health’ as “a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity”.
So until, a consensus is reached on the severity of the disease in question, we can, as educated individuals, try to overlap these studies with the given definition of health and formulate our own perspective to answer the question: Is an obese person, without systemic diseases like diabetes, cardiac disease etc., actually healthy?