I don’t think obesity itself is contagious (unless you’re mucking about in an obese person’s fecal matter). My hunch is antibiotic usage disrupts your gut biome enough that it pushes your energy extraction balance off, causing obesity.
As a society, we abuse antibiotics in the aggregate (demanding it from health care providers and pouring it into factory farms). It can’t possibly not be disrupting our guy biome.
It also doesn’t help that the sugar lobby/industry is so powerful, and sugar/corn syrup is in everything.
Eg anecdotally I can see people in India putting on the pounds much more than Chinese---whether on the mainland or in South-East Asia like Singapore. But I don't know the statistics off the top of my head, I only lived there.
As a society, we abuse antibiotics in the aggregate (demanding it from health care providers and pouring it into factory farms). It can’t possibly not be disrupting our guy biome.
It also doesn’t help that the sugar lobby/industry is so powerful, and sugar/corn syrup is in everything.