In this episode, Dr. David Jockers sits down with Vanessa Spina, sports nutrition specialist, bestselling author of Keto Essentials, creator of the Tone ketone breath analyzer, and host of the Optimal Protein Podcast, for a deep dive on a groundbreaking new study out of the University of Nottingham, published in Clinical Nutrition in August 2025.
You will learn why the old "you can only absorb 30 grams of protein per meal" rule doesn't hold up, what really happens to protein you eat beyond that amount, and why the popular anabolic-window advice to slam a shake right after your workout is largely a myth. Dr. Jockers and Vanessa then break down a randomized, controlled fasting-mimicking diet study that overturns the long-held belief that high protein blocks autophagy, and explain why a high-protein, calorie-restricted approach can outperform a low-protein one for visceral fat loss, ketone production, and metabolic health.
They close with a practical, hour-by-hour walkthrough of the protein-sparing modified fast (PSMF): what to eat, how much protein to target, how to structure refeed days, and how it compares to water fasting and Ozempic for appetite control.
In This Episode:
00:00 Protein Absorption Myth
00:14 Episode Intro and Study Teaser
05:29 Meet Vanessa and Study Setup
07:35 100g Protein Study Breakdown
12:17 Protein Timing and Real Life
17:48 Protein First for Satiety
23:55 Ketones and High Protein Keto
28:10 Stress Hormones and Growth Hormone
31:58 Autophagy Study Lead In
33:12 Why Human Trials Matter
34:52 Autophagy Headlines vs Reality
35:54 High Protein FMD Study Setup
39:01 Autophagy Still Upregulated
40:53 Visceral Fat and Metabolic Wins
44:12 PSMF One Day Weekly
44:58 Vanessa PSMF Results
47:22 Meals Macros and Refeeds
51:21 Ketones Hunger and Ozempic
55:27 Weekly Schedule and Whoosh
58:26 PSMF Meal Ideas and Tips
01:04:06 Water Fast vs PSMF
01:05:54 Wrap Up and Where to Find
01:06:56 Final Listener Outro
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"Optimizing your protein acts just as well, if not better, than taking a semaglutide medication — without those side effects and a fraction of the cost."
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Resources:
Visit paleovalley.com/jockers to get 15% off Paleo Valley's Turmeric Complex and other products
Visit iRestore.com and use code DRJOCKERS for Labor Day savings on the iRestore Elite and Illumina face mask bundle
Visit superpower.com and use code JOCKERS to get $20 off your SuperPower Health membership
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Study referenced: The effects of a short-term (1-week) very low-calorie diet comparing low and normal protein content on cardiometabolic outcomes, glucose metabolism and autophagy — University of Nottingham (Clinical Nutrition, August 2025)
Connect with Vanessa Spina:
Website: ketogenicgirl.com
Instagram: https://www.instagram.com/ketogenicgirl/
Podcast: https://podcasts.apple.com/podcast/id1344681226
Connect with Dr. Jockers:
Instagram – https://www.instagram.com/drjockers/
Facebook – https:/www.facebook.com/DrDavidJockers
YouTube – https://www.youtube.com/user/djockers
Website – https://drjockers.com/
If you are interested in being a guest on the show, we would love to hear from you! Please contact us here! - https://drjockers.com/join-us-dr-jockers-functional-nutrition-podcast/