In this episode, Greg Dickens and I discuss a set of recent papers summarising the evidence on ultra-processed food. We talk about the effect of childhood stress in rats, and how their gut microbes influence this. We then explore the problems that arise when women are transported during labour, and how this disrupts the normal hormonal processes of birth. We finish by talking about why drinking a smoothie has very different effects on the body from eating the same fruit whole, and why just focusing on the individual nutrients isn’t enough to understand the complexity of the system.

For more information on why moving labouring women disrupts their hormones, see this article:

https://guenbradbury.substack.com/p/donkeys-cars-or-boats-why-transporting

For more information on how birth should work in humans, try this talk:

https://guenbradbury.substack.com/p/veterinary-perspectives-on-childbirth

Topics covered

* What do we know now about ultra-processed foods, and what should society do?

* How do probiotics help stressed rats?

* What is physiological birth and why should we care about it?

* What can we do to enable physiological birth?

* Why is whole fruit better than smoothies?

These other podcasts cover related topics:

Notes

“The rise of ultra-processed foods (UPFs) in human diets is damaging public health, fuelling chronic diseases worldwide, and deepening health inequalities. Addressing this challenge requires a unified global response that confronts corporate power and transforms food systems to promote healthier, more sustainable diets, according to a new Lancet Series on UPFs and human health, published on Nov 19.” https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(25)02322-0/fulltext

Mild environmental stress inoculation promotes resilience to anxiety in female rats: https://www.nature.com/articles/s41598-025-24717-x

Processing Apples to Puree or Juice Speeds Gastric Emptying and Reduces Postprandial Intestinal Volumes and Satiety in Healthy Adults: https://www.sciencedirect.com/science/article/pii/S0022316622023586

Hello! My name’s Guen. I’m a veterinarian by background and I’ve worked in health innovation for a decade. I spent eighteen months living in traditional villages across Africa and South America, learning from communities that raise children in very different ways. My passion is helping parents, doctors, and teachers identify small things they can do to set children up for better long-term physical health.

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