teaser
Mon, Sep-09-13, 06:21
http://www.sciencedaily.com/releases/2013/09/130908135833.htm
Yin-Yang Effect of Sodium and Chloride Presents Salt Conundrum
Sep. 8, 2013 — Eat less salt' is a mantra of our health-conscious times and is seen as an important step in reducing heart disease and hypertension.
Too much salt in the diet -- and specifically sodium -- is widely acknowledged as a major risk factor for high blood pressure however, scientists have found that salt's other oft-overlooked constituent chloride might also play an important role.
A study by researchers at the University of Glasgow has revealed that low chloride levels in the blood is an independent indicator of mortality risk in people with hypertension. The role of chloride in hypertension has received little attention from scientists hitherto.
After analysing data from almost 13,000 patients with high blood pressure, followed up over 35 years, the researchers found that low levels of chloride was associated with a higher risk of death and cardiovascular disease.
The group with the lowest level of chloride in their blood had a 20% higher mortality rate compared to the other subjects. The results are published in the journal Hypertension.
Dr Sandosh Padmanabhan of the Institute of Cardiovascular and Medical Sciences, said: "Sodium is cast as the villain for the central role it plays in increasing the risk of high blood pressure, with chloride little more than a silent extra in the background.
"However, our study has put the spotlight on this under-studied chemical to reveal an association between low levels of chloride serum in the blood and a higher mortality rate, and surprisingly this is in the opposite direction to the risks associated with high sodium.
"It is likely that chloride plays an important part in the physiology of the body and we need to investigate this further."
Chloride is already measured as part of routine clinical screening and so monitoring of chloride levels could easily be incorporated into clinical practice to identify individuals at high risk.
Dr Padmanabhan added: "The results we see from this study are confounding against the knowledge that excess salt is a bad thing, yet higher levels of chloride in the blood seems to be an independent factor that is associated with lower mortality and cardiovascular risk. We seem to have entered a grey area here that requires further investigation.
"It is too early to draw any conclusions about relating this finding to salt intake and diet. We need more research to establish exactly what the relationship between chloride and health risk is."
http://www.sciencedaily.com/releases/2013/09/130908135833.htm
I'm not sure of the paradox here. They don't do much to defend the dangers of sodium in the article.
I find the abstract interesting;
Serum Chloride Is an Independent Predictor of Mortality in Hypertensive Patients
Chloride (Cl−) is the major extracellular anion in the body, accompanying sodium (Na+), and is primarily derived from dietary sources. Data suggest that increased dietary Cl− intake increases blood pressure, yet paradoxically, higher serum Cl− appears associated with lower mortality and cardiovascular risk. This implies that serum Cl− also reflects risk pathways independent of blood pressure, serum Na+, and bicarbonate (HCO3−). We analyzed 12 968 hypertensive individuals followed up for 35 years, using Cox proportional hazards model to test whether baseline serum Cl− was an independent predictor of mortality. To distinguish the effect of Cl− from Na+ and HCO3−, we adjusted for these electrolytes and also performed the analysis stratified by Na+/HCO3− and Cl− levels. Generalized estimating equation was used to determine the effect of baseline Cl− on follow-up blood pressure. The total time at risk was 197 101 person-years. The lowest quintile of serum Cl− (<100 mEq/L) was associated with a 20% higher mortality (all-cause, cardiovascular and noncardiovascular) compared with the remainder of the subjects. A 1 mEq/L increase in serum Cl− was associated with a 1.5% (hazard ratio, 0.985; 95% confidence interval, 0.98–0.99) reduction in all-cause mortality, after adjustment for baseline confounding variables and Na+, K+, and HCO3− levels. The group with Na+>135 and Cl−>100 had the best survival, and compared with this group, the Na+>135 and Cl−<100 group had significantly higher mortality (hazard ratio, 1.21; 95% confidence interval, 1.11–1.31). Low, not high Serum Cl− (<100 mEq/L), is associated with greater mortality risk independent of obvious confounders. Further studies are needed to elucidate the relation between Cl− and risk.
In those cases where sodium is above a certain level, and so is chloride... I'd suspect table salt might be the "culprit." When sodium is at that level, but chloride is lower... perhaps the sodium is being found elsewhere. Baking soda? Or maybe it's just a sign of metabolic dysregulation.
Yin-Yang Effect of Sodium and Chloride Presents Salt Conundrum
Sep. 8, 2013 — Eat less salt' is a mantra of our health-conscious times and is seen as an important step in reducing heart disease and hypertension.
Too much salt in the diet -- and specifically sodium -- is widely acknowledged as a major risk factor for high blood pressure however, scientists have found that salt's other oft-overlooked constituent chloride might also play an important role.
A study by researchers at the University of Glasgow has revealed that low chloride levels in the blood is an independent indicator of mortality risk in people with hypertension. The role of chloride in hypertension has received little attention from scientists hitherto.
After analysing data from almost 13,000 patients with high blood pressure, followed up over 35 years, the researchers found that low levels of chloride was associated with a higher risk of death and cardiovascular disease.
The group with the lowest level of chloride in their blood had a 20% higher mortality rate compared to the other subjects. The results are published in the journal Hypertension.
Dr Sandosh Padmanabhan of the Institute of Cardiovascular and Medical Sciences, said: "Sodium is cast as the villain for the central role it plays in increasing the risk of high blood pressure, with chloride little more than a silent extra in the background.
"However, our study has put the spotlight on this under-studied chemical to reveal an association between low levels of chloride serum in the blood and a higher mortality rate, and surprisingly this is in the opposite direction to the risks associated with high sodium.
"It is likely that chloride plays an important part in the physiology of the body and we need to investigate this further."
Chloride is already measured as part of routine clinical screening and so monitoring of chloride levels could easily be incorporated into clinical practice to identify individuals at high risk.
Dr Padmanabhan added: "The results we see from this study are confounding against the knowledge that excess salt is a bad thing, yet higher levels of chloride in the blood seems to be an independent factor that is associated with lower mortality and cardiovascular risk. We seem to have entered a grey area here that requires further investigation.
"It is too early to draw any conclusions about relating this finding to salt intake and diet. We need more research to establish exactly what the relationship between chloride and health risk is."
http://www.sciencedaily.com/releases/2013/09/130908135833.htm
I'm not sure of the paradox here. They don't do much to defend the dangers of sodium in the article.
I find the abstract interesting;
Serum Chloride Is an Independent Predictor of Mortality in Hypertensive Patients
Chloride (Cl−) is the major extracellular anion in the body, accompanying sodium (Na+), and is primarily derived from dietary sources. Data suggest that increased dietary Cl− intake increases blood pressure, yet paradoxically, higher serum Cl− appears associated with lower mortality and cardiovascular risk. This implies that serum Cl− also reflects risk pathways independent of blood pressure, serum Na+, and bicarbonate (HCO3−). We analyzed 12 968 hypertensive individuals followed up for 35 years, using Cox proportional hazards model to test whether baseline serum Cl− was an independent predictor of mortality. To distinguish the effect of Cl− from Na+ and HCO3−, we adjusted for these electrolytes and also performed the analysis stratified by Na+/HCO3− and Cl− levels. Generalized estimating equation was used to determine the effect of baseline Cl− on follow-up blood pressure. The total time at risk was 197 101 person-years. The lowest quintile of serum Cl− (<100 mEq/L) was associated with a 20% higher mortality (all-cause, cardiovascular and noncardiovascular) compared with the remainder of the subjects. A 1 mEq/L increase in serum Cl− was associated with a 1.5% (hazard ratio, 0.985; 95% confidence interval, 0.98–0.99) reduction in all-cause mortality, after adjustment for baseline confounding variables and Na+, K+, and HCO3− levels. The group with Na+>135 and Cl−>100 had the best survival, and compared with this group, the Na+>135 and Cl−<100 group had significantly higher mortality (hazard ratio, 1.21; 95% confidence interval, 1.11–1.31). Low, not high Serum Cl− (<100 mEq/L), is associated with greater mortality risk independent of obvious confounders. Further studies are needed to elucidate the relation between Cl− and risk.
In those cases where sodium is above a certain level, and so is chloride... I'd suspect table salt might be the "culprit." When sodium is at that level, but chloride is lower... perhaps the sodium is being found elsewhere. Baking soda? Or maybe it's just a sign of metabolic dysregulation.