Dr Simon Thornley is an epidemiologist, lecturer, researcher and public health physician working at the University of Auckland in the section of Epidemiology and Biostatistics. He graduated from the University of Auckland with a Bachelor of Human Biology in 1997, a Bachelor of Medicine and Bachelor of Surgery in May 2000 a Master of Public Health with First Class Honours in 2006 and a Doctor of Philosophy in Medicine in 2015.
Dr. Thornley's research interests include tobacco dependence, food addiction and obesity, cardiovascular disease, diabetes, psychiatric disease, injury and environmental epidemiology. He has completed a PhD on cardiovascular risk factors and has a particular interest in the health effects of sugar and low carb lifestyles.
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Orientation
- Simon Thornley is an epidemiologist who uses numbers to decide what works and what does not in medicine.
- The talk collects nutrition topics from recent months: diet evidence, fasting, and major new weight-loss drugs.
Network meta-analysis for diet evidence
- Pair-wise meta-analysis compares one option against another; network meta-analysis links many options through shared comparators.
- Direct and indirect comparisons combine into a single network that ranks many diets at once.
- P-score ranks the chance that one diet beats the rest; a diet network meta-analysis puts low carbohydrate at about 0.9.
- Meta-analyses depend on inputs, yet many syntheses place keto/low carbohydrate ahead of low fat and Mediterranean patterns. Fasting and time-restricted eating
- Fasting is used as a way to rest the pancreas; solid academic evidence is scarce.
- A time-restricted eating trial with an 8-hour window (12 to 8) beats calorie restriction by about two-fold.
Carnivore diet survey paper
- Evidence in journals is sparse; a recent US paper by David S Ludwig and colleagues surveys adults on a carnivore diet.
- Recruitment runs through social media; eligibility is age ≥18 and carnivore diet duration ≥6 months.
- Mean BMI drops about 2.9 units, about 9.2 kg for a 1.78 m person.
- The survey answers include LDL rising, which supports honesty on other outcomes such as weight loss.
LDL thresholds and cardiovascular risk
- LDL cut-points sit far left on the distribution, so many people fall into the "abnormal" zone.
- Low LDL cut-points support a large market for lipid-lowering drugs.
- LDL links weakly with cardiovascular events in risk prediction; triglycerides track cardiovascular risk more strongly and move in the right direction on carnivore.
Drug effect size metrics and survival time
- Wegovy and similar drugs are promoted heavily at conferences; benefit numbers often use relative effects like 19% for all-cause mortality.
- Absolute effects matter: 0.44% absolute risk reduction maps to NNT ≈225 over 4 years to avert one death.
- Restricted mean survival time uses the area between Kaplan–Meier curves to express average survival gain as time.
- For one GLP-1 drug, 4 years of use yields about one week of average survival gain.
- For statins, 6 months to 6 years of use yields about one to three weeks of average survival gain in industry-funded trials.
- For dulaglutide, 6 years of use yields about 17 days of average survival gain; cost is about $500/month for one GLP-1 example.
Wrap-up
- Network meta-analysis helps sort nutrition evidence across many diet options.
- Early data on carnivore looks strong; LDL alarm is amplified by low thresholds.
- Restricted mean survival time makes drug benefits easier to understand as days or weeks of survival.
References
- [00:07] Behavioral Characteristics and Self-Reported Health Status among 2029 Adults Consuming a "Carnivore Diet" — https://doi.org/10.1093/cdn/nzab133