Cristóbal Morales
Head of the Metabolic Health, Diabetes and Obesity Unit at Vithas Hospital in Seville and member of the Spanish Society for the Study of Obesity (SEEDO)
The article is a gem; it's truly beautiful and of great interest. We were already familiar with the general idea, but having four generations of Britons genetically studied and shown to have the current environment—the obesogenic society—amplify the expression of these genes that regulate hunger and satiety is significant. This obesity epidemic isn't actually due to a change in genes, but rather it's the change in environment that allows genetic predisposition to manifest itself more strongly.
A possible headline would be that your postal code makes your genetic code express itself much more strongly. If in children born in the post-war period of 1946 the effect of genetics had an impact of 0.46 on body mass index, we now see that this force has doubled in this latest generation. The obesogenic society causes the genes that predispose us to obesity to express themselves more strongly.
There are also three very important points. First, regarding the unequal distribution of risk, we see that the most obese people have a greater expression of these genes. This helps us understand the biological causes that lead people to be overweight or obese.
Second, it raises a public health issue and the obligation to legislate to protect this population, understanding the impact of obesogenic society on gene expression. And third: we need to move towards precision medicine and delve deeper into diagnosis, because today we know that genetic predisposition sometimes accounts for 50-70% of this weight gain. For me, the headline would be that our postal code is amplifying, is winning out over our genetic code.
It's not simply that genetics itself is changing; what's changing is the expression of those genes, which are currently being expressed twice as strongly as in previous generations. We need to understand this; it compels us to act.
In short, the article is truly excellent, and the methodology is quite good. It provides plenty to discuss, generates much debate, and presents an uncomfortable truth that we have an obligation to address as a public health problem.