Many cancer cells rely heavily on glucose (the Warburg effect) and cannot efficiently use ketones. A strict ketogenic diet may starve these tumors while nourishing healthy cells. In one case, it led to a 70% reduction in cancer markers in six weeks, far exceeding chemotherapy's expected 30%.

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.

While short-term keto adaptation (first month) may show no power gains, long-term adaptation (6-18 months) trains muscles to efficiently use fat as fuel. This results in significant power increases, with studies on soldiers showing up to a 50% improvement over their non-keto counterparts.

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.

The anxiolytic effect of ketosis has a clear neurochemical basis. Elevated ketones increase the levels of the enzyme GAD (glutamic acid decarboxylase), which converts the brain's primary excitatory neurotransmitter, glutamate, into its primary inhibitory (calming) neurotransmitter, GABA, creating a more stable neurological state.

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 7-year study of healthy individuals over 85 found minimal genetic differences from their less healthy counterparts. The key to their extreme healthspan appears to be a robust immune system, which is significantly shaped by lifestyle choices, challenging the common narrative about being born with "good genes."

Nutritional research shows that dietary diversity is a more critical health factor than simply eliminating animal products. People who consume 30 or more different kinds of plants and animals weekly are significantly freer from disease than even those on exclusively vegan or vegetarian diets.