Monday, January 9, 2012
SALT: TO EAT OR NOT TO EAT
Consequently, salt has been vilified to such extent in the media that may people strive to remove it from their diets completely. But is wiping salt out of the menu really a wise choice? According to a recent study published in the Journal of the American Medical Association, not exactly.
To understand both why salt is healthy and why it has the potential to be dangerous, let's look at what it can do for us. The primary biological role of sodium is to regulate blood volume and blood pressure by maintaining adequate body fluid levels. When the kidneys detect too little sodium levels in the body, they decrease sodium excretion. But when there is too much sodium, an antidiuretic hormone kicks in and causes the body to retain water. The kidneys will then try to gradually release excess sodium and water through urine, thus bringing the body's fluid and sodium levels back within normal ranges.
Water and salts are also lost through excessive perspiration, associated with hot climates and physical effort. This can severely offset the body's internal regulating mechanisms, and adequate rehydration is advised as soon as possible. In normal conditions however, sodium regulation is left almost entirely up to the kidneys. Medical experts usually warn us that if for some reason, the kidneys are unable to excrete excess sodium, the increased blood volume will exert extra pressure on blood vessels and make the heart work harder.
But now scientists say that too little sodium is just as bad. On the one hand, sodium deficiency can cause a range of problems, including headaches, nausea, fatigue and muscle cramps. On the other hand, commercially available foods contain large amounts of hidden salt which makes it difficult for people on a traditional diet to control their sodium intake.
The research of professors Martin J. O'Donnell and Salim Yusuf of McMaster University in Ontario, Canada now reveals that if we have very low levels of sodium in urine, we are at risk of cardiovascular death and congestive heart failure. The study looked at 28,880 people, with an elevated risk of cardiovascular disease, over a seven-year period.
The scientists explained that "clarifying the optimal daily intake of sodium is particularly important in patients with established cardiovascular disease, where it has been inadequately studied." However, there is no scientific consensus as of yet regarding optimal salt intake, since body sodium levels also depend on how much an individual sweats.
"As a general rule, if people are adding salt to their diet they are taking in too much and they are on the higher end of our spectrum. The first thing people need to do is stop adding salt," said O'Donnell. Fortunately, certain foods are naturally rich in sodium and can help balance a diet without added salts. Seaweed, green leafy vegetables and tuberous vegetables are natural sources of sodium, as well as other essential salts, such as magnesium and potassium.