UK study reignites debate over healthy obesity

A new study suggests that people who are obese with no health complications are still more likely to develop heart disease than those who are not overweight and in similar metabolic health.
Previous research suggested that obese people might be protected from cardiovascular events if they didn’t have poor metabolic health, a condition sometimes referred to as “metabolically healthy obesity”.
Scientists have now shown that even if obese people are free of type 2 diabetes and don’t have risk factors for metabolic syndromen, like high blood pressure or cholesterol imbalance, they still have an increased risk of heart disease.
In the new study, researchers at the University of Birmingham analysed the electronic health records of three and a half million British patients who were followed from 1995 through to 2015.
They have found that people who are obese and considered metabolically healthy still have a 50 per cent greater risk of heart disease and twice the risk of developing heart failure than people with a normal weight.
People who fall in the metabolically healthy category and were merely overweight were at a 30 per cent greater risk of coronary heart disease (CHD) compared to their normal weight and metabolically healthy peers.
These figures are slightly higher than what similar research released last August had found. It was estimated that the increased risk was 26 and 28 per cent for the overweight and obese participants, respectively.
There are however some limitations to the current research. Key issues include the inability to judge cause and effect and the near-impossible task of controlling for all the potential factors that might influence the outcomes.
For example, the records didn’t capture lifestyle habits, so the study failed to account for the wide-ranging effects of diet. The analysis also didn’t take fitness level or physical activity into account.
People who are metabolically healthy, moderately obese and keeping fit, or are actively trying to lose weight, may have a decreased risk of developing heart disease.
In addition to this, the new study found that being overweight and obese is often associated with inflammation, which may contribute to cardiovascular disease, regardless of metabolic measures.
Overall, these findings suggest that while markers of metabolic health may be a predictor of heart disease, achieving a healthy weight with lifestyle modifications may be just as important to improve health.
The findings were published in the Journal of the American College of Cardiology.