Dr. Annette Bosworth: Why insulin fuels chronic disease

Bosworth explains that most patients are “making buckets of insulin” for years due to late‑night eating, frequent snacking, high‑carb processed foods, and constant grazing. Even when fasting glucose and HbA1c look ‘normal’, the high insulin needed to keep them normal fuels fat gain, high blood pressure, cancer growth, and brain ‘trash’ that precedes depression, brain fog, Parkinson’s and Alzheimer’s. Practical red flags she cites include abdominal fat, skin tags, velvety darkened skin on the neck or elbows (acanthosis nigricans), loss of hair on toes and legs, and needing to eat every 2–3 hours to avoid energy crashes.

Glucose is stored as glycogen; as long as glycogen stores are available and insulin remains high, the body will preferentially burn sugar and lock away fat. Bosworth notes that some significantly insulin‑resistant patients on 20 g total carbs per day take 10–15 days before they register any ketones. For very resistant individuals, simply ‘cutting carbs for a few days’ may not be enough—more aggressive tactics like multi‑day low‑carb adherence, earlier eating windows, or short fasts are needed to truly deplete glycogen, lower insulin, and switch to fat oxidation.

Ketones generate less oxidative ‘trash’ than glucose and cross the blood‑brain barrier even when the brain is insulin resistant. Bosworth reports drastic differences in her own clinical stamina, mood stability, and irritability depending on whether she is in ketosis, and describes podcasters and students who notice sharper focus and verbal fluency when fasting or keto compared to high‑carb days. She uses ketones strategically in brain‑compromised patients, including dementia and brain injury cases, to bypass impaired glucose utilization and improve concentration, engagement, and emotional regulation.

Bosworth lays out a 12‑step continuum: starting from eating every 2–3 hours with no carb limits, then moving to <20 g total carbs (Step 2), achieving urine ketones and naturally skipping meals, then implementing time‑restricted feeding (e.g., 16:8), gradually tightening the eating window earlier into the day, and eventually to 23:1 one‑meal‑a‑day and periodic 36–72 hour fasts for those with long‑standing insulin resistance. Crucially, she emphasizes that you “never fall all the way off”—if you slip, you drop back a few steps, not to zero, and you always verify progress with objective ketone and glucose measurements rather than guesswork.

Using finger‑stick monitors, they measure Steven’s glucose (86 mg/dL) and ketones (0.9 mmol/L) and Bosworth’s (83 and 1.7), then compute the ‘Dr. Boz ratio’ (glucose in mg/dL divided by ketones in mmol/L). Ratios under ~100 suggest active fat burning; much lower ratios (e.g., <40) are her target for serious conditions like cancer or autoimmune disease. In contrast, a staff member with glucose 88 and ketones 0.1 (ratio ~880) exemplifies someone producing little to no ketones and “making lots of trash.” She argues that five days of morning readings will quickly reveal whether someone is insulin resistant and whether their regimen is actually working.