4 ms·
For the past year I've been on a low sodium diet, not so easy to achieve. After reviewing the renal physiology I learned about years ago re: sodium and calcium
by jrapdx3 9y ago
For the past year I've been on a low sodium diet, not so easy to achieve. After reviewing the renal physiology I learned about years ago re: sodium and calcium regulation, I'll testify it's every bit as complex as I remember and then some.
I'll be interested in reading the articles the newspaper report is based on, but ATM not sure how much the new findings contradict (vs. extend) what's thought to be true about the physiological roles of sodium. In terms of implications for health issues, conditions like hypertension are enormously heterogeneous in origin, salt intake being only one factor among a huge number of factors involved.
I was interested in the comment that high salt intake was potentially adverse for bone health via glucocorticoid stimulation. One thing I've recently learned is how high dietary sodium negatively affects bone calcium balance via mechanisms within bone cells, and in some people, excessive renal calcium excretion as well. These issues aren't AFAIK primarily mediated by elevated cortisol. So it seems to be suggesting another way high sodium intake promotes bone loss.
Goes to show we know a lot less than we think we know, in this case about body regulation of essential minerals like sodium and calcium. When we realize that also applies to every other factor we think related to high blood pressure or osteoporosis, it's very humbling indeed.
- epmaybe 9y agoA random theory, if you will: glucocorticoids have a weak affinity for the mineralocorticoid receptors (aldosterone, salt and water retention). The increased salt reabsorption caused by this could cause an osmotic gradient driving calcium excretion. It sounds a bit too complicated though, where a transporter would fit in nicely.
- jrapdx3 9y agoI don't have any direct info re: mineralocorticoid effect on renal reabsorbtion of calcium, however the interaction of sodium and calcium has been studied as it is important in kidney disease, for example kidney stones, and osteoporosis as well. Here is an article on an excellent site that discusses some of the significant aspects of sodium/calcium regulation: http://kidneystones.uchicago.edu/does-too-much-protein-increase-stones-or-damage-bones/ http://kidneystones.uchicago.edu/does-too-much-protein-incre....