Estudo questiona que sal provoca tensão alta:
http://www.dailymail.co.uk/health/article-4443612/Low-salt-diets-not-lower-blood-pressure.html
Citando:
"Researchers followed more than 2,600 men and women over a period of 16 years
They discovered that consuming less salt wasn't linked to lower blood pressure
New findings call into question salt limits recommended by dietary guidelines
Cutting salt from your diet may not be the answer to lower blood pressure, a study has found.
The NHS advice is for adults to eat no more than six grams of salt a day – the equivalent of 2.4 grams of sodium.
But a study by Boston University found people consuming less salt than this actually had higher blood pressure, prompting a call for the guidance to be changed.
Researchers say the advice to eat less salt is too simple and ignores the fact that salt can raise hormone levels in the body which regulate and keep blood pressure low.
(...)
While many people with heart disease who cut salty, processed food out of their diet do see their blood pressure fall, these tend to be 'salt-sensitive' people, which may be why they have bad hearts to begin with.
Salt can cut blood pressure in some people, but the experts say potassium, found in bananas and potatoes, can help tip the balance too, along with magnesium and calcium.
Levels of these could explain why some people who consumed more than six grams of salt had lower blood pressure."