Why Most People Are Insulin Resistant (It's Not What You Think) | Dr. Sarah Myhill
What if insulin resistance starts at the cellular power plant, not the dinner plate?
What this episode covers
- Sarah Myhill is a UK clinician known for her work on chronic fatigue syndrome (CFS).
- In this interview she pushes a 'mitochondria-first' interpretation of insulin resistance: the body becomes insulin resistant because the cellular power plants can't process fuel efficiently, and chronic carbohydrate excess overwhelms an already-fragile system.
- Her recommended template is paleo-ketogenic, with fasting, magnesium, B-vitamins, and CoQ10 (coenzyme Q10) layered on top.
- Some of this is mainstream (refined-carb avoidance, fasting, the link between metabolic dysfunction and fatigue).
- Some is more contested (mitochondria-first ordering, supplement protocols at the doses she recommends, generalizability beyond her CFS patient population).
Why it matters
Insulin resistance is the upstream driver of most modern chronic disease. Whether you frame it as 'too much sugar' or 'mitochondria can't process fuel,' the practical levers — cut refined carbs, restore time without food — are the same.
What stands out
- Insulin resistance is more common in normal-BMI (body mass index) adults than most people assume. Lean does not equal metabolically healthy (mechanistic + observational).
- Fasting insulin moves before glucose does. Testing only glucose hides the problem (mechanistic).
- Most 'mitochondrial support' supplements lack RCT evidence in the absence of measured deficiency (RCT review).
This is one of multiple expert perspectives. The full topic combines them into clear guidance.Explore full topic →
One key action from this episode
Cut refined carbohydrates and seed oils first; layer in a 12-14 hour overnight fast before adding supplements.
What to do
Actions discussed in this episode. This is what one expert recommends — the full topic compares and ranks across experts.
- Action: Cut refined carbohydrates (sugar, white flour, sweetened beverages) and minimize seed oils for 8-12 weeks. Limitation: This works for insulin resistance with intact thyroid and adrenal function. If you have unexplained severe fatigue or symptoms of thyroid dysfunction, get those screened first. Fork: If full reduction is unrealistic, start with sweetened beverages alone, the highest-yield single change. Cost of Wrong: Replacing sugar with low-fat, refined-carb 'diet' products keeps insulin elevated. Reinforce: Fasting insulin and HOMA-IR (the Homeostatic Model Assessment for Insulin Resistance, calculated from fasting glucose and insulin) generally respond within 8 weeks. This is the cheapest, most-supported lever.
- Action: Adopt a 12-14 hour overnight fast (e.g., last bite by 7 pm, first bite at 8 am). Limitation: People with a history of disordered eating, pregnant or breastfeeding, those with diabetes on insulin, or anyone severely underweight should not start fasting without supervision. Fork: If 12 hours is hard, start with 10 hours and add 30 minutes per week. Cost of Wrong: Pushing aggressive intermittent fasting (16-20 hour windows) on someone already metabolically stressed can worsen sleep, mood, and adherence. Reinforce: Overnight fasting is the most sustainable pattern long-term and the version with the strongest safety profile.
- Action: Test, don't guess on supplements. Get fasting insulin, HOMA-IR, magnesium RBC, B12, vitamin D, and ferritin before starting any supplement protocol. Limitation: Some labs aren't routine — you may need to specifically request fasting insulin and magnesium RBC. Fork: If your insurance won't cover them, services like InsideTracker or Function Health offer paid panels. Cost of Wrong: Blanket supplementation with magnesium, B-vitamins, and CoQ10 can mask deficiencies and cost money without measurable benefit. Reinforce: A single $100-200 panel re-orients an entire supplement strategy. Most 'mitochondrial support' stacks are guesswork without the data.
Full context, impact ratings, and timing — available in related topics
Questions to take to your doctor
Questions worth asking based on this episode
- What is my fasting insulin and HOMA-IR (not just glucose)?
- Is my magnesium or B12 actually low on bloodwork — or am I supplementing in the dark?
- Would a 3-month carb-quality intervention be a reasonable first step before supplements?
Full doctor prep with ranked questions available in the full topic page
This is one expert perspective. The full topic ranks actions across multiple experts.Explore full topic →
Context
How this expert sees it
Dr. Sarah Myhill approaches this through the lens of clinical evidence and practical application. The emphasis is on what you can actually change, not just what the science shows.
What we don't know yet
That mitochondrial dysfunction is definitively upstream of insulin resistance.
That ketogenic eating reverses insulin resistance in everyone.
That blanket supplementation with CoQ10/magnesium/B-vitamins benefits all adults.
That protocols from a CFS clinic generalize to everyone with insulin resistance.
Where people go wrong
- Going full ketogenic without first reducing refined carbs.Most of the benefit comes from cutting refined carbs and seed oils. Going to <50g/day adds difficulty without proportional benefit for most.
- Stacking 'mitochondrial support' supplements without baseline labs.Spending $100+/month on supplements that may not address an actual deficiency, while ignoring the diet-and-sleep levers that move the needle.
What to expect over time
- Weeks 1-2Cravings and energy fluctuations as the body adapts to lower refined-carb intake. Sleep quality often improves first.
- Weeks 4-8Fasting insulin and HOMA-IR start to drop measurably. Waist circumference and weight may fall as a side effect.
- Months 3-6HbA1c shifts; if fatigue was present, energy stabilizes. Reassess labs and decide whether to layer on more targeted supplementation.
This is one expert's perspective. The full topic shows where experts agree and disagree.Explore full topic →