1 Answer

While humans can safely ingest small amounts of salt, the salt content in seawater is much higher than what can be processed by the human body. In addition, when we consume salt in our daily diet, we also drink liquids, which help dilute the salt and keep it at a healthy level. While living cells depend on sodium chloride to maintain the chemical balances and reactions that take place at the cellular level, too much sodium can be deadly.

http://www.catalogs.com/info/gadgets/why-can%27t-humans-drink-saltwater.html

http://www.straightdope.com/columns/read/2131/what-would-happen-to-you-if-you-drank-seawater

1.       Blood pressure

Drinking salt water can have unfavorable effects on the blood pressure. It makes the blood pressure to plummet high which further causes other effects on the body. High blood pressure puts excessive pressure on the heart putting its proper functioning in great jeopardy.

2.       Heart rate

To cope with the increased blood pressure which occurs on drinking salt water, the heart rate goes up too. Increased respiration rate and greater perspiration results from this which, if anything increases the loss of water from body.

3.       Physiological changes

Besides these changes, seafarers are advised not to drink sea water because it can make body functioning improper. Headache, dizziness, nausea, blood stained stool, vomiting etc are just a few of the many physiological symptoms that occur upon excessive intake of salt water of the sea. These changes only hasten the deterioration process of the body, robbing seafarers of precious time for survival.

4.       Excessive thirst

Drinking salt water of sea comes as one of the last resorts to seafarers when out on sea. However, it fails the very purpose it is done for. One of the major effects of drinking salt water is not quenching of thirst but an augmentation in it. Due to excessive salt content of seawater, the body does not register the water in it but only the salt. As such, there would be no satiation but only maddening desire to drink more and more water.

5.       Brain damage

Large amount of salt in sea water affects all the body functioning, including the brain activity as well. The increases salt content of this water upsets the salt balance of body fluids and affects the brain activity severely.

6.       Loss of consciousness

As a result of drinking salt water and all the physiological changes that occur from it, the seafarers can even lose consciousness. This could be result of any of these changes- excessive water loss, too much salt content in body, improper brain functioning etc.

7.       Impairment of judgment

Impairment of judgment or going crazy, as it is also referred to sometimes is one of the major effects of drinking salt water. The scientific explanation for this is that upon intake of seawater, a seafarer would not really be satiated. His thirst would rather increase. However, with presence of copious amount of water in front of him, he would want to continue drinking more water, being unable to control the thirst.

8.       Dehydration

Due to the osmosis, drinking water with too much salt in it will cause the water from the cells of body to go into body fluids to balance the salt content. This will cause dehydration of cells disrupting their normal functioning.

9.       Kidney failure

In long term, kidney failure occurs when sea water is taken for an extended period. Since human kidneys are not designed to handle such large amount of salt in body fluids, renal failure is the unavoidable under such conditions.

10.    Death

What follows from all these little and big symptoms is death. And if you wonder- how can you drink salt water and face a fate any worse than dying? Then the answer is yes you can because this takes away the time a seafarer might have until the help arrives.