Adding Medium-Chain Triglyceride (MCT) oil to exogenous ketone supplements (like BHB salts or esters) leads to a higher and more prolonged elevation of blood ketone levels than taking either substance alone. The MCT oil slows the absorption of the supplemental ketones, extending their effect.

Dr. Fred Hatfield, a famous powerlifter, reportedly achieved years of remission from metastatic prostate cancer by implementing a 'sardine fast.' This protocol involved consuming only one can of sardines per day for one week each month, similar to a fasting-mimicking diet.

Ferriss notes significant physiological changes while in ketosis, including needing 2-3 fewer hours of sleep and at least doubling his breath-hold time. He also experiences a dramatic reduction in ruminative thoughts, improving mental clarity and sleep onset.

The goal of fiber is to feed gut bacteria that produce butyrate, a key acid for gut health. However, you can bypass this. Being in a ketogenic state directly provides beta-hydroxybutyrate (a ketone) to the gut, strengthening the microbiome without requiring high fiber intake.

Beyond being an alternative fuel source, the ketone body beta-hydroxybutyrate (BHB) functions as a signaling molecule. It acts as an HDAC inhibitor, which can activate genes that enhance the body's antioxidant and cellular defense mechanisms, a pathway of interest in cancer therapy.

Research published in Nature Medicine indicates that ketogenic and vegan diets impact the immune system differently. While a vegan diet tends to enhance the broad, non-specific innate immune system, a ketogenic diet was shown to augment the more specialized adaptive immune system (T-cells and B-cells).

Many chronic illnesses, including high blood pressure, cancer, and cognitive decline, are not separate issues but symptoms of a single underlying problem: chronically elevated insulin levels. This metabolic “trash” accumulates over years, making the body a breeding ground for disease.

Ketones are a more efficient energy source than glucose, producing less metabolic “trash” (oxidative stress). Crucially, they can penetrate the blood-brain barrier and fuel brain cells even when they've become resistant to insulin, directly combating cognitive decline and brain fog.

The time required to enter ketosis varies dramatically. A healthy person might take a few days, but someone with years of high insulin resistance could need over two weeks of strict low-carb dieting to deplete their massive glycogen stores and begin producing ketones. This manages expectations and prevents premature failure.