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I read somewhere that eating a lot of salt will raise blood pressure, which will in turn damage brain tissue. This is because water molecules gather around salt ions, thus making it harder for the body to remove the excess water from the blood.

Is this true? How much salt is actually dangerous?

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This thread may be helpful. –  terdon Nov 30 '12 at 11:43
    
Eating salt raises blood pressure that is true. Increased blood pressure is a risk factor in a variety of diseases. Sodium however is also essential in the diet, as sodium and potassium are the key elements involved in generating action potentials in neurons. –  Mew Jan 19 '13 at 0:35
    
I have recently read about a murder by force feeding salt to a kid. Tragically, the kid went crazy and then died...See also en.wikipedia.org/wiki/Hypernatremia and hawaii.edu/medicine/pediatrics/pemxray/v3c14.html –  Memming Sep 3 '13 at 0:36
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Good question. The answer really depends. There is a normal range of plasma sodium concentration that ranges from about 135 to 145 mM. You body has multiple endocrinologic and neurological mechanisms to closely regulate this concentration. So even if you went out and ate a ton of salty snacks, your body would still keep your plasma sodium concentration within this range. A salt concentration much lower or greater than this can start to cause problems depending on how fast it happens and how far from the normal value. Brain surgery patient are often given lots of extra salt to keep their brains "salty" as this protects from cerebral edema and counteracts salt wasting that often occurs with brain injury. However, the opposite or very high sodium concentrations are also not good. As you said, a diet high in salt can lead to high blood pressure and chronic high blood pressure can cause damage the small blood vessels in the brain and cause small strokes over time or very high blood pressure can cause larger bleeds. Usually we see this in patients with very high uncontrolled blood pressures in the 170-200s systolic range. I'm kind of pulling those numbers out of my memory and you would have to check the literature to verify.

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Thanks for the answer. I have a very frequent and apparently strong pulse, but low blood pressure. Does low blood pressure mean that I'm 'safer' when eating salt than other people? Also how do I detect small strokes? –  jco Sep 8 '13 at 13:15
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