I know that to much sodium causes high blood pressure,... But how does sodium make blood pressure high?

Answer 1

When a solution contains more stuff dissolved in it than another solution and these are separated by a membrane, water will spontaneously move to the solution of higher concentration. When there are large amounts of sodium in your blood, water from elsewhere in the body will diffuse into the bloodstream to equalize the concentration. Thus, you will have a larger volume of fluid in your blood vessels which will result in higher pressure.

Answer 2

To much sodium makes it difficult to lower high blood pressure, for the reasons stated by others, but as to what the cause of high blood pressure in any given individual person is. This is completely unknown by any Doctor or Group of Doctors.

Answer 3

Water will go where the salt is. It's all about osmotic pressure. So if you retain salt, you're going to retain water. So your intravascular volume will increase and that results in an increase in blood pressure. Hypertension is really about the kidney's ability to get rid of the sodium.

Answer 4

When the sodium levels get too high in your blood, your kidneys release a hormone that initiates a cascade of actions to increase the rate of sodium excretion by raising the blood pressure Sodium excretion is increased by higher blood pressure. The higher pressure literally pushes sodium molecules through the membranes of the kidneys and into the urine.

Answer 5

It isn't so simple. Salt only increases BP in salt-sensitive individuals. There are 2 types of essential hypertension - excess volume and excess renin. If your have hypertension caused by excess renin and you lower sodium intake you could actually increase BP. Why?
Decreased sodium induces the kidneys to secrete more renin, which converts angiotensinogen into angiotensin I, which is then converted by ACE into angiotensin II which has many effects; constriction of blood vessels, increased thirst leading to increased blood volume, it stimulates the pituitary to excrete ADH and the adrenal cortex to excrete aldosterone, both leading to further renal fluid retention.
Incidentally, 2 of 3 people with hypertension have the excess renin type, so a blanket homogeneous edict to 'decrease sodium' could be causing more harm than good.

Answer 6

Sodium in the blood increased bonding with water, increasing blood volume, and in the process, creating higher natural pressures in the blood with each heart beat.