Animal-Based Fat and Testosterone

Does animal fat affect testosterone?

Chris Brandlin argues that dietary fat from animal sources plays a meaningful role in hormone health, and points to the research he finds most persuasive on declining testosterone levels in men over recent decades.

His broader claim is that the long push toward low-fat eating was never a neutral recommendation. It changed what ended up on the plate at scale, and he contends the downstream effects on hormone health were never seriously accounted for. That is the same thread running through the trans fats and seed oils video — the seed oils versus animal fats question is, in his telling, a rerun of an argument the public already lost once.

It is worth being direct about the status of this: nutrition science here is genuinely contested, and he presents it as his own reading of the evidence rather than as settled consensus. Anyone weighing a change should read the underlying studies and talk to a physician who knows their history.

Where it connects to policy is dietary guidance itself — what public institutions recommend, and how confidently. That is the public-health thread behind the AD-42 platform.

Related: a carnivore cookbook worth reading and the full public health policy series.

Nothing here is medical advice.