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.

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.

Alcohol temporarily reduces anxiety by boosting the neurotransmitter GABA. However, the brain overcompensates by converting GABA into glutamate, an excitatory neurotransmitter. This rebound effect leaves you more anxious than before, creating a self-perpetuating cycle of self-medication.

Baszucki finds he can directly influence his mood through diet. Being in ketosis induces a state of "calm optimism," making challenges feel solvable. Conversely, a glucose crash simulates minor depression, making problems seem untenable. This suggests a direct link between metabolic state and psychological outlook.

A moderate level of blood ketones, around 1.2 to 2 millimolars, can have an anxiolytic (anxiety-reducing) effect. However, spiking ketone levels significantly higher, often through large doses of exogenous supplements, can paradoxically increase anxiety and lead to a subsequent crash.

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.