Australian researchers found that patients who
had highest levels of sodium in their urine had the smallest risk of dying over
a 10-year period.
Endocrinologists Dr. Elif Ekinci and Dr. George
Jerums, who worked on the study, felt that the result was unexpected. They say,
"It raises the possibility that in people with Type 2 diabetes, low salt
intake is not always beneficial. Such data call into question universal
recommendations in the journal Diabetes Care, that all adults should endeavor
to reduce their salt intake".
But readers, especially diabetics, don't reach
for the pack of chips as yet! Although it isn't the first time that findings
like these have come up, the researchers relied on just observations and didn't
actually run an experimental study to test the direct impact of consuming more
or less salt.
Instead, researchers followed 638 people who had
longstanding Type 2 diabetes, often accompanied by high blood pressure and
heart disease. All patients who enrolled for the study were in their 60s on an
average and nearly half of them were obese. Researchers note, "These are
precisely the patients in whom more aggressive lifestyle interventions are
The patients were treated at a single diabetes
clinic. When the study began, doctors determined the daily amount of sodium in
their urine. The researchers noticed that the average amount of sodium in their
urine (4.2g per day) was in line with earlier global surveys. For every extra
2.3g of sodium in their urine, the risk of dying during the study dropped by 28
percent, even after accounting for kidney disease, age and other factors.
At this point, however, no change in the current dietary advice is recommended as the new
study doesn't prove that additional salt helps diabetics live longer. Dr. Paul
Elliott, who studies the link between high blood pressure and diet at Imperial
College London says, "The main problem is that the patients who had lower
sodium levels in their urine were sicker and older".
Dr. Elliott further adds, "Although the
researchers used statistical models to 'correct' these imbalances, it remains
likely that the results are still confounded by them".
Dr. Michael H. Alderman of the Albert Einstein
College of Medicine in New York comments, "The reality is that reducing
sodium has many effects, some good like reducing average blood pressure, and
some bad. For instance, reducing sodium increases insulin resistance, which is
the main problem in diabetes. It also elevates the production of certain other
hormones that have been linked to heart disease". "The impact of reducing
sodium must be the sum total of all these physiological effects", he adds.
Scientists suggest, getting to the bottom of the
issue, a clinical trial comparing people told to eat less sodium to those who
maintain their usual intake is necessary.