The Proof with Simon Hill

The Keto Study That Wasn't About Keto | Dr Nicola Guess

The Proof with Simon Hill

Show Notes

Practising registered dietitian and senior research fellow at the University of Oxford, Dr Nicola Guess, returns to the show to discuss a new study whose findings were interpreted in quite different ways the week it came out. Dr Samuel Klein’s group at Washington University assigned people with prediabetes to one of three diets, carefully controlled their weight loss, and found that the arm labelled ketogenic reduced liver fat by 67%.

Nicola’s view is that the label, and the conclusion many drew from it, deserve a closer look. Ketone levels in that arm were lower than you would typically expect on a ketogenic diet, which suggests something other than ketosis may explain the result. Her reading is that protein intake, rather than carbohydrate restriction, could be the more important variable. With roughly one in three adults carrying excess fat in the liver, often without symptoms, understanding what actually drives that reduction matters for the advice people receive.

What We Cover

Why this trial should not have been called a ketogenic diet study

How protein appears to lower liver fat even in the absence of weight loss

The 23% saturated fat arm, and why ApoB fell anyway

What likely changes once people move from weight loss into maintenance

Whether liver fat causes insulin resistance or simply marks it

Nicola's 35 grams of protein per meal target and how she builds a plate around it

Where seed oils and fibre actually sit in the evidence

This is a good example of why the label on a study matters as much as its headline number. If you have been told to cut carbohydrates to fix your liver, this conversation is worth your time.

To connect with Nicola Guess, visit NicolaGuess.com or find her on Instagram and YouTube.

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