Can You Be Obese and Healthy?
Many people believe that if someone is obese, they automatically are unhealthy and will develop type 2 diabetes. However, the authors of a new study explain that not only is this not true for everyone who is greatly overweight, but that a certain molecule may explain why.
This discovery is important for several reasons, not least of which is that it may help researchers eventually better treat metabolic diseases such as type 2 diabetes. Since obesity is such an important risk factor for this metabolic disorder, which is reaching epidemic proportions, the results could be highly significant.
Basically, a scientific team headed by Harald Esterbauer of the Medical University of Vienna found that high levels of a molecule called HO-1 are associated with poor metabolic health and a greater risk of developing type 2 diabetes among obese individuals. Therefore, substances that can block HO-1 might represent a future treatment option for this and other metabolic conditions.
It’s been observed that not every obese individual goes on to experience poor metabolic health or to develop type 2 diabetes. At the same time, researchers have noted that metabolic inflammation has a role in these health issues. Therefore, a team of researchers decided to look at the relationship between HO-1 (which has been believed to have anti-inflammatory properties) and metabolic disease.
The team found higher amounts of HO-1 in obese, insulin-resistant (a type 2 diabetes risk factor) individuals compared with their obese, metabolically healthy peers. Surprisingly, they also found that when they took away the HO-1 gene in immune cells in mice, signs of inflammation declined. This finding suggested that the HO-1 molecule promotes inflammation rather than helps fight it.
In addition, deleting the HO-1 gene in the liver or certain cells called macrophages in mice who were fed a high-fat diet resulted in an improvement in liver function and better insulin sensitivity or, put another way, they were less resistant to insulin. Insulin resistance means that the sugar in the bloodstream is not taken up adequately by the cells, resulting in high blood sugar levels.
This study is not the first to indicate that obesity can be a healthy state for some individuals. In a study published in Applied Physiology, Nutrition and Metabolism in 2011, for example, the authors noted that not everyone who is obese needs to lose weight to be healthy. Naturally, anyone who is overweight or obese should take steps to screen for health issues commonly associated with obesity, including type 2 diabetes, high cholesterol, high blood pressure, and sleep apnea, among others.
The bottom line for this new study is that the HO-1 molecule is a strong predictor of poor metabolic health among obese individuals. Thus the molecule could help in identifying the onset of type 2 diabetes, especially among significantly overweight patients. The authors concluded that their findings “identify HO-1 inhibition as a potential therapeutic strategy for metabolic disease,” including type 2 diabetes.
Jais A et al. Heme oxygenase-1 drives metaflammation and insulin resistance in mouse and man. Cell 2014; 158(1): 25-40.
Kuk JL et al. Edmonton Obesity Staging System: association with weight history and mortality risk. Applied Physiology, Nutrition, and Metabolism 2011 Aug; 36(4): 570-76