The common perception of pigs consuming nearly anything, including human remains, often extends to a misconception about their ability to digest teeth. However, the scientific reality reveals that human teeth possess unique properties that render them largely impervious to the pig’s powerful digestive system. Understanding the biological mechanisms of both pigs and human teeth clarifies why these durable structures are an exception to the pig’s broad diet.
The Pig’s Diet and Digestive Capabilities
Pigs are omnivores, eating a wide variety of plant and animal matter. They forage for roots, leaves, fruits, and insects, and also consume small mammals or carrion. Their digestive system is adapted to process this diverse intake. The stomach of a mature pig is highly acidic, typically maintaining a pH range of 1.5 to 2.5 due to hydrochloric acid secretion.
This strong acidity helps to break down food particles and activate digestive enzymes. The pig’s stomach secretes pepsin, an enzyme that hydrolyzes proteins. Further digestion occurs in the small intestine, where enzymes like amylase, lipase, and trypsin act on carbohydrates, fats, and proteins. While effective at processing organic materials for nutrient absorption, these processes are primarily geared towards breaking down softer, biologically active components.
The Remarkable Durability of Human Teeth
Human teeth are among the most robust biological structures in the body, designed to withstand significant mechanical forces during chewing. They are composed of three highly mineralized tissues: enamel, dentin, and cementum. Enamel, the outermost layer covering the tooth crown, is the hardest substance in the body.
Enamel consists of approximately 95% to 98% inorganic material, primarily as crystalline hydroxyapatite. Hydroxyapatite is a calcium phosphate mineral that provides exceptional hardness and resistance to degradation. Dentin, beneath the enamel, and cementum covering the tooth root, also contain significant amounts of hydroxyapatite, though less mineralized than enamel. This dense mineral composition makes teeth exceptionally resilient compared to other biological tissues.
Why Teeth Resist Digestion
Despite the pig’s powerful jaws and highly acidic stomach, human teeth largely resist complete chemical digestion. While a pig’s stomach acid can cause dental erosion over prolonged contact, it is not sufficient to rapidly dissolve the highly mineralized structure of teeth. Unlike organic matter, teeth contain minimal protein or fat, the primary targets for digestive enzymes in a pig’s stomach and intestines.
The crystalline hydroxyapatite forming tooth structure is particularly stable and impervious to enzymatic action. If swallowed, teeth typically pass through the digestive tract mostly intact or as undigested remnants. Research on hydroxyapatite nanoparticles indicates that even at low gastric pH, their dissolution can be incomplete. The unique mineral composition of teeth, rather than their physical size, is the primary reason they are not broken down and absorbed for nutritional value.