&gt; But if obesity is primarily the fault of the person who is obese lacking will power then shouldn&#x27;t we start by doing things directly addressing this.<p>Yes, we should. The average weight has gone up far faster than humans can change genetically, so people start looking for things like gut flora or epigenetics. Occam&#x27;s razor would point to the average supermarket and restaurant selection of today versus a few generations ago to explain the obesity epidemic. Cheaper, faster, tastier food (capitalism optimizes for these three qualities in food), and more riveting, less active indoor pursuits can easily explain it. That&#x27;s not to say the research is worthless, but gut biome most likely influences subconscious cravings, <i>not</i> BMR, and epigenetics is still young enough that many biologists think that pulling conclusions from research into it is premature at best.