Where dietary amino acids go in the body

I sit down with Dr Luc van Loon to unpack what really happens to protein in the body, from digestion to muscle and organ tissue. We explore why muscle protein synthesis is often misunderstood, how inactivity drives muscle loss, and what the research actually says about protein needs across the lifespan.

What We Cover

• Ice baths and their impact on muscle adaptation
• Protein absorption, muscle protein synthesis, and common myths
• Anabolic resistance and the role of physical activity
• Protein needs in ageing, illness, and recovery
• Plant based versus omnivorous diets and muscle health

A deep dive into protein science, ageing, and what matters most for preserving muscle and function.

• Intro (00:00)
• How Protein Research Evolved in Exercise Physiology (02:07)
• How Muscle Protein Synthesis Actually Works (Mechanisms Explained) (04:01)
• Tracing Amino Acids From Food Into Muscle Tissue (07:00)
• Biggest Myths About Protein Intake (What the Public Gets Wrong) (10:02)
• Protein Digestion, Absorption, and Where Amino Acids Go (17:25)
• Anabolic Resistance Explained: Why Muscle Response Declines With Age (38:16)
• How Much Protein Do You Really Need? Optimal vs Adequate Intake (46:41)
• How Protein Digestion Studies Are Designed (And Their Limitations) (53:22)
• Omnivore vs Vegan Diets: Muscle Protein Synthesis Compared (1:00:12)
• Protein Quality vs Quantity: What Actually Builds Muscle (01:08:52)
• Protein Powders, Isolates, and Supplements: Do They Help? (01:11:08)
• Protein Requirements (01:15:08)
• IGF1, Protein Consumption and Cancer (01:16:32)
• Amino Acids Explained: How the Body Rebuilds Protein From Steak (01:22:34)
• Anabolic Response Explained: When Amino Acids Actually Build Muscle (01:28:59)
• Supplements and Muscle Protein Synthesis (01:30:35)
• Muscle Protein Turnover, Aging, and Preventing Muscle Loss (01:38:59)

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Simon Hill, MSc, BSc (Hons)

• Creator of theproof.com
• Host of The Proof with Simon Hill
• Author of The Proof is in the Plants

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