Limits of precision and human adaptability

Dr Walter Willett has spent more than fifty years at the forefront of nutrition research, leading landmark studies that have shaped how we think about fat, carbohydrates, protein and chronic disease. In this episode, he joins me to untangle decades of confusion around saturated fat, seed oils, dairy, eggs, plant protein and more, and to explain what a truly healthy dietary pattern looks like when you consider both human health and planetary health.

We explore how evidence from long term cohorts, clinical trials and global dietary patterns converges on a common theme, and what the Planetary Health Diet means in practical terms for you and your family.

What We Cover

• How nutrition science has evolved and why the big picture is now clearer.

• Why the source of fat and carbohydrate matters more than the amount.

• The truth about seed oils, saturated fats, and dairy.

• Protein quality, plant to animal ratios, and what matters most for longevity.

• How diet affects cognitive ageing and dementia risk.

• The planetary health diet and how to eat for both people and planet.

This is a nuanced, evidence based conversation with one of the most influential nutrition scientists of our time. I hope it helps you feel less confused and more empowered in the choices you make every day.

• The Fat Misconception of the 1970s (00:01:35)
• Media, Internet & Public Misinformation (00:05:36)
• Current Blind Spots & Future Predictions (00:09:55)
• Dietary Changes & Public Health Impact (00:13:47)
• Why the Mediterranean Diet Still Leads the Pack (00:18:02
• How Nutrition Research Really Works (00:23:33)
• Fats, Oils, and the Myths That Won’t Die (00:32:57)
• Dairy: Health vs. Environmental Costs (00:45:35)
• Protein Intake & Healthy Aging (00:59:57)
• Fiber's Role in Health (01:19:59)
• Can Diet Protect Our Brain? (01:29:43)
• Food Choices and the Future of the Planet (01:40:48)

This episode is brought to you by:

38TERA

Consider 38TERA's DMN prebiotic supplement a daily multivitamin for your gut. Formulated by yours truly and gastroenterologist Dr Will Bulsiewicz. Use code THEPROOF for a discount at checkout.

Function Health

Take charge of your health with advanced blood testing and personalised insights. Function Health offers a practical way to track key health markers such as cholesterol, blood sugar, and more. Learn more and join at functionhealth.com/simonhill for a $25 credit toward your membership. Only available to those living in the United States.

LMNT

Stay hydrated with LMNT. Get a free Sample Pack of LMNT’s most popular drink mix flavours with any purchase at DrinkLMNT.com/SIMON Find your favourite LMNT flavour, or share with a friend. And if you don’t like it? Full refund, no questions asked.

IM8

With 92 nutrients, including Vitamin B12, Iodine, Selenium and Vitamin D, in highly absorbable forms, IM8 Daily Essentials is the perfect all-in-one daily multi-vitamin to ensure you meet your daily micronutrient needs. IM8 is offering an exclusive 10% off your first order with a free welcome kit when you enter the promo code SIMON at checkout on im8health.com

Eight Sleep

Upgrade your sleep with the Pod 5 Ultra by Eight Sleep. Clinically validated to deliver up to 1 extra hour of quality sleep per night through temperature control and biometric tracking. Use code THEPROOF for $400 off at eightsleep.com/theproof. Try it risk-free for 30 days, with worldwide shipping.

SKIMS

Upgrade your underwear drawer with SKIMS Mens. Soft, stretchy and built to stay in shape, they provide comfort and freedom of movement for training or everyday wear. Shop SKIMS Mens at SKIMS.com. Let them know we sent you! After you order, select "podcast" in the survey and choose The Proof from the dropdown. And if you’re looking for the perfect gifts this season - the SKIMS Holiday Shop is now open at SKIMS.com.