20 Hours of ZERO Food Does This to the Body - Fasting OVER 16 Hours

DeLauer emphasizes that the 16-hour mark is the critical threshold where the body transitions into a state of heightened fat burning and cellular repair. Around 14-15 hours, individuals often experience a shift in energy, increased focus, and a 'good hunger' that indicates the body is utilizing its own stored fat. This period is when the body starts breaking down unused cellular components (autophagy) and shifting away from glucose as a primary fuel source, leading to a more efficient metabolic state.

Once the body has shifted into fat-burning mode around the 16-hour mark, engaging in low-intensity, steady-state exercise like a weighted walk can significantly amplify the benefits. This type of activity helps to 'cram' fat through the system, forcing the mitochondria to adapt more quickly to using fat as fuel. This accelerates the transition into deeper states of autophagy and fat burning, making the fasting process more efficient.

DeLauer highlights a study published in BMC Rheumatology that investigated alternate day fasting's impact on arthritis, particularly rheumatoid arthritis. The study found that this fasting pattern significantly reduced 543 genes linked to arthritis, including Interleukin 33, a cytokine associated with specific joint pain. He likens fasting to increasing the 'volunteers' for cellular cleanup, consolidating resources for repair rather than growth. This approach allows the body to actively repair and reduce systemic inflammation, addressing the 'creaky' feeling often experienced with age.

DeLauer advocates for grounding, or earthing, during a fast as a simple yet effective way to amplify benefits. He explains that connecting directly with the earth's surface, by standing barefoot on natural ground, can lead to a measurable reduction in cortisol levels and systemic inflammation. He cites heat map and inflammation studies that demonstrate these physiological changes, emphasizing that humans were designed to be connected with the earth and that this practice helps restore that natural balance.

Thomas DeLauer explains that ghrelin, while causing hunger, is not inherently bad for fat loss. He cites a study in 'Current Opinions in Clinical Nutrition and Metabolic Care' showing that ghrelin drives autophagy. This means that when you feel hungry during a fast, especially after 16 hours, it's often a sign that your body is starting to break down its own cells and tissues for energy and repair. The initial discomfort of hunger can transition into a feeling of 'good hunger' as the body adapts to using its stored resources.

DeLauer points out that a change in urine odor, becoming 'different' or stronger, is a real sign of increased autophagy. This is due to the breakdown of metabolites and components, leading to increased urea, sulfur compounds, and ammonia excretion. Similarly, breath odor changes, often described as a 'sweet smell' or 'morning breath,' occur around 15-16 hours as muscle glycogen depletes and ketone production increases. Ketones, specifically breath acetone, can increase by over 3.5 times, signaling a deeper state of autophagy and the activation of genetic and epigenetic benefits associated with fasting.

DeLauer explains that feeling cold in a fasted state is a significant indicator of deep autophagy and fat burning. He clarifies that it's not a rapid metabolic slowdown, which takes much longer to occur. Instead, the body intelligently prioritizes repair mechanisms over maintaining core body temperature, much like a smart business person cutting non-essential costs to invest in critical areas. This reallocation of energy signifies that the body is in a 'survival mode' where repair is paramount, leading to a temporary reduction in heat generation.

DeLauer describes how fasting can lead to remarkably vivid dreams, sometimes with a sense of control, and even a peculiar 'nocturnal awareness' where one is conscious of sleeping. He attributes this to increased Brain-Derived Neurotrophic Factor (BDNF) and neuroplasticity, which enhance communication between brain regions. Additionally, elevated orexin, a wakefulness hormone, during sleep in a fasted state, can lead to a lighter REM cycle but paradoxically deeper neuronal repair. This suggests the body requires less sleep while still achieving significant brain repair, a finding supported by rodent studies showing reduced sleep requirements in fasted states.