Programmed cell death. Apoptosis is a type of cellular self-destruct mechanism that rids the body of damaged or aged cells. Unlike necrosis, a process in which cells that die as a result of acute injury swell and burst, spilling their contents over their neighbors and causing a potentially damaging inflammatory response, a cell that undergoes apoptosis dies in a neat and orderly fashion – shrinking and condensing, without damaging its neighbors. The process of apoptosis is often blocked or impaired in cancer cells. (May be pronounced “AY-pop-TOE-sis” OR “AP-oh-TOE-sis”.)

An intracellular degradation system involved in the disassembly and recycling of unnecessary or dysfunctional cellular components. Autophagy participates in cell death, a process known as autophagic dell death. Prolonged fasting is a robust initiator of autophagy and may help protect against cancer and even aging by reducing the burden of abnormal cells.

The relationship between autophagy and cancer is complex, however. Autophagy may prevent the survival of pre-malignant cells, but can also be hijacked as a malignant adaptation by cancer, providing a useful means to scavenge resources needed for further growth.

A gene encoding a transcription factor (CLOCK) that affects both the persistence and period of circadian rhythms. CLOCK functions as an essential activator of downstream elements in the pathway critical to the generation of circadian rhythms. In humans, polymorphisms in the CLOCK gene have been associated with increased insomnia, weight loss difficulty, and recurrence of major depressive episodes in patients with bipolar disorder.

The process in which information stored in DNA is converted into instructions for making proteins or other molecules. Gene expression is highly regulated. It allows a cell to respond to factors in its environment and involves two processes: transcription and translation. Gene expression can be turned on or off, or it can simply be increased or decreased.

Restricting the timing of food intake to certain hours of the day (typically within an 8- to 12-hour time window that begins with the first food or non-water drink) without an overt attempt to reduce caloric intake. TRE is a type of intermittent fasting. It may trigger some beneficial health effects, such as reduced fat mass, increased lean muscle mass, reduced inflammation, improved heart function with age, increased mitochondrial volume, ketone body production, improved repair processes, and aerobic endurance improvements. Some of these effects still need to be replicated in human trials.