Drinking saltwater poses health risks to humans. While water is essential, seawater’s high salt concentration makes it detrimental rather than hydrating. Consuming it can lead to severe health problems throughout the body.
The Body’s Salt Management System
The human body possesses a system for regulating salt balance through the kidneys. These organs are responsible for filtering waste products and excess salt from the blood, producing urine. The kidneys work to maintain a precise balance of fluids and electrolytes within the body, ensuring proper cell function.
However, seawater presents a challenge to this system due to its high salinity. Seawater contains about 3.5% dissolved salts, or approximately 35 grams per liter. This concentration is much higher than the salt level in human blood, which is around 0.9% or 9 grams per liter. To excrete the excess salt ingested from seawater, the kidneys must produce urine saltier than the body’s own fluids. This process demands more water than was consumed, leading to a net loss of water from the body and dehydration.
The Process of Cellular Dehydration
When saltwater is ingested, the high concentration of salt increases the salt content in the bloodstream. This creates a condition where the fluid surrounding the body’s cells becomes “hypertonic,” meaning it has a higher solute (salt) concentration than the fluid inside the cells. To equalize this imbalance, a process called osmosis occurs.
During osmosis, water molecules move across semi-permeable cell membranes from an area of lower solute concentration to an area of higher solute concentration. Water is drawn out of the body’s cells and into the bloodstream to dilute the excess salt. This movement of water causes the cells to shrink and become dehydrated, compromising their normal functions. Despite the consumption of liquid, the body’s cells are deprived of water, leading to systemic dehydration.
Severe Physiological Effects
The cellular and systemic dehydration caused by drinking saltwater leads to severe health consequences. Initial symptoms include intense thirst, fatigue, and dizziness, as the body struggles with fluid imbalances. Reduced urine output is common, as the kidneys attempt to conserve water while excreting the salt load.
As dehydration progresses, the body’s organs begin to suffer from the lack of water and the salt overload. More serious issues include muscle cramps, nausea, and vomiting, further exacerbating fluid loss. Eventually, it can lead to kidney failure, as the organs are pushed beyond their capacity to filter and excrete salt. Neurological symptoms such as delirium, confusion, and seizures may develop due to disrupted brain cell function. Severe cases can lead to the body’s systems shutting down completely, leading to unconsciousness, coma, and death.