Biochemistry answers for common weight loss questions: Sodium. (warning, long and nerdy)
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HellYeahItsKriss wrote: »Aaron_K123 wrote: »Aaron_K123 wrote: »HellYeahItsKriss wrote: »So, This post was pretty awesome, i actually learned some things i didn't know and it has actually prompted a question... or a few haha
So lets say i have a day where my sodium is high, say 5000 mg, I know that i don't really have any issues with water retention staying within the default 2300, but i do retain once i start creeping up and up.. so.. back to 5000mg cause usually thats a typical number in sodium i hit when i over kill.. How many ml of water per mg of sodium would be good to drink to balance yourself? I am the type that retains water for at least 3-4 days after, if i drank this amount of water to restore balance, would that cut the amount of retention i experience down some, since i tend to pee pretty quickly after consuming liquids, Or would drinking enough water to balance out just cause issues?
Oh boy good question I don't know off the top of my head but I might look into that and try to respond. Off the top of my head I'd imagine the solution to the question is just to know the natural level of sodium that is considered balanced in your body and use that to figure out how much water.
The way it gets complicated is that water is required for lots of bodily functions not related to sodium like for digestion so not all the water you drink would be available for bringing the sodium to the desired concentration. So therefore whatever I'd calculate just off of the desired sodium concentration you'd probably need to drink more water than just that. How much more hard to say.
That said if you know how much water you need to drink when you have 2300mg sodium we should be able to calculate how much more water you'd need for 5000mg using that method. Just have to look up what the natural sodium concentration is in your body (ie weight of sodium per liter of water)
Okay I am at a computer now so I can look things up to try to give an answer. So here are the numbers I found that we need.
Here is my source: http://book.bionumbers.org/what-are-the-concentrations-of-different-ions-in-cells/
Okay so sodium in mammalian blood plasma is about 100 to 200 mM, lets call it 150mM. In comparison sea water is 500 mM. So your blood is really only about 3 times less salty than sea water. Not suprisingly when I looked up medical saline it looks like it is at a concentration of 154mM, which is right in line with the concentration in your blood https://en.wikipedia.org/wiki/Saline_(medicine). So if you are dehydrated and in a hospital they are going to hook you up to water that is only about 3 times less salty than sea water.
mM is a measure of concentration called millimolar. What 150mM of sodium means is that there are 150 milimoles per liter. A mole is a specific number of atoms. To convert that to weight we need to know the atomic weight of sodium which is on the periodic table and is 23 grams per mole which is the same as 23 miligrams per milimole. So what that means is 150 milimoles is the same as 150*23 = 3450 mg per liter. Wow, that is a ton isn't it. That is the amount of sodium in your blood right now. In comparison a liter of diet soda (that drink lots of people on here love to claim is high in sodium) has about 120mg in a liter...about 30 times less than what is in your blood. So yeah just a thought for people who claim soda is high in sodium. If you drink soda you are actually diluting the sodium concentration of your body, not increasing it.
Anyways, on to your question. You compared going from taking in 2300mg of sodium to taking in 5000mg. Lets pretend that the amount of food you eat is the same, its just much higher sodium content food. That would be an additional 2700mg of sodium. Given your blood has a concentration of 3450 mg per liter that would mean to take that 2700mg and put it at the same concentration that is in your blood you would only need to dissolve it in 780 mL of water. Call it an extra liter.
The reason though that we drink water and not salt water is because water is used for much more in our bodies than just solubilizing sodium so not all of the water you drink can be used to dilute out the sodium that you take in. All other variables held constant though yeah you'd only need to drink about an extra liter of water to hold that extra sodium in check...I think.
Haha, wow.. Thank you for taking the time for that, I will give that a try next time i sodium binge and let you know how long before i see my current weight again. Although i will probably just use tap water, those bottled waters are expensive enough as it is lol..
As a visual comparison of your brain and my own.. This post is a great display of your brain and its impressiveness and this photo is me.. hahaha
I mean I wouldn't really try to go off my math or anything that was just for fun and to attempt to answer but I was making assumptions and I can't guarantee I'm like 100% right, go off urine color if anything. If darker than straw drink more water, if lighter than straw then drink less water or feel free to have more sodium. Hydration and sodium intake go hand in hand.5 -
Aaron_K123 wrote: »I have thought about doing this on the regular, that is why I made the title I did "Biochemistry answers for common weight loss questions: Sodium" so that if it is popular at all or people find it useful I might do another that is "Biochemistry answers for common weight loss questions: XXXX" for another topic, probably answering where your weight actually goes when you lose weight. Don't want to commit just yet though, not sure if this sort of long-winded technical description is something people actually want. If it stays up for a while or gets a lot of discussion I might do another.BrookeLynn18 wrote: »I would really enjoy this!
I'd have fun writing others if people are interested. Biochem or molecular bio perspective on weight loss or myths/misconceptions associated with weight loss. Not sure if forum posts are the right format or a blog, or maybe some sort of sticky area if that is of interest to the moderators/admins and people would like it (not to sound overly arrogant just a thought)9 -
Oddly, my urine color is only slightly darker first thing in the morning, even with the 5000mg sodium days, It also doesnt seem to take much to change the color, i had to drink 1.5L of water for a pelvic ultrasound the other day and my pee was pretty much clear for the first few pees lol..0
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HellYeahItsKriss wrote: »Aaron_K123 wrote: »Aaron_K123 wrote: »HellYeahItsKriss wrote: »So, This post was pretty awesome, i actually learned some things i didn't know and it has actually prompted a question... or a few haha
So lets say i have a day where my sodium is high, say 5000 mg, I know that i don't really have any issues with water retention staying within the default 2300, but i do retain once i start creeping up and up.. so.. back to 5000mg cause usually thats a typical number in sodium i hit when i over kill.. How many ml of water per mg of sodium would be good to drink to balance yourself? I am the type that retains water for at least 3-4 days after, if i drank this amount of water to restore balance, would that cut the amount of retention i experience down some, since i tend to pee pretty quickly after consuming liquids, Or would drinking enough water to balance out just cause issues?
Oh boy good question I don't know off the top of my head but I might look into that and try to respond. Off the top of my head I'd imagine the solution to the question is just to know the natural level of sodium that is considered balanced in your body and use that to figure out how much water.
The way it gets complicated is that water is required for lots of bodily functions not related to sodium like for digestion so not all the water you drink would be available for bringing the sodium to the desired concentration. So therefore whatever I'd calculate just off of the desired sodium concentration you'd probably need to drink more water than just that. How much more hard to say.
That said if you know how much water you need to drink when you have 2300mg sodium we should be able to calculate how much more water you'd need for 5000mg using that method. Just have to look up what the natural sodium concentration is in your body (ie weight of sodium per liter of water)
Okay I am at a computer now so I can look things up to try to give an answer. So here are the numbers I found that we need.
Here is my source: http://book.bionumbers.org/what-are-the-concentrations-of-different-ions-in-cells/
Okay so sodium in mammalian blood plasma is about 100 to 200 mM, lets call it 150mM. In comparison sea water is 500 mM. So your blood is really only about 3 times less salty than sea water. Not suprisingly when I looked up medical saline it looks like it is at a concentration of 154mM, which is right in line with the concentration in your blood https://en.wikipedia.org/wiki/Saline_(medicine). So if you are dehydrated and in a hospital they are going to hook you up to water that is only about 3 times less salty than sea water.
mM is a measure of concentration called millimolar. What 150mM of sodium means is that there are 150 milimoles per liter. A mole is a specific number of atoms. To convert that to weight we need to know the atomic weight of sodium which is on the periodic table and is 23 grams per mole which is the same as 23 miligrams per milimole. So what that means is 150 milimoles is the same as 150*23 = 3450 mg per liter. Wow, that is a ton isn't it. That is the amount of sodium in your blood right now. In comparison a liter of diet soda (that drink lots of people on here love to claim is high in sodium) has about 120mg in a liter...about 30 times less than what is in your blood. So yeah just a thought for people who claim soda is high in sodium. If you drink soda you are actually diluting the sodium concentration of your body, not increasing it.
Anyways, on to your question. You compared going from taking in 2300mg of sodium to taking in 5000mg. Lets pretend that the amount of food you eat is the same, its just much higher sodium content food. That would be an additional 2700mg of sodium. Given your blood has a concentration of 3450 mg per liter that would mean to take that 2700mg and put it at the same concentration that is in your blood you would only need to dissolve it in 780 mL of water. Call it an extra liter.
The reason though that we drink water and not salt water is because water is used for much more in our bodies than just solubilizing sodium so not all of the water you drink can be used to dilute out the sodium that you take in. All other variables held constant though yeah you'd only need to drink about an extra liter of water to hold that extra sodium in check...I think.
Haha, wow.. Thank you for taking the time for that, I will give that a try next time i sodium binge and let you know how long before i see my current weight again. Although i will probably just use tap water, those bottled waters are expensive enough as it is lol..
Oh, one more thing I should have mentioned. The amount of water I said, one liter, would be the amount needed to balance out the sodium...you'd retain all that water. If you wanted to start flushing sodium out of your body and decrease the amount of water you were retaining you'd want to drink much more than that. Like probably twice as much.1 -
HellYeahItsKriss wrote: »Oddly, my urine color is only slightly darker first thing in the morning, even with the 5000mg sodium days, It also doesnt seem to take much to change the color, i had to drink 1.5L of water for a pelvic ultrasound the other day and my pee was pretty much clear for the first few pees lol..
Yeah I mean it doesn't take all that much water to offset it. People way overkill with the water sometimes.0 -
Aaron_K123 wrote: »HellYeahItsKriss wrote: »Aaron_K123 wrote: »Aaron_K123 wrote: »HellYeahItsKriss wrote: »So, This post was pretty awesome, i actually learned some things i didn't know and it has actually prompted a question... or a few haha
So lets say i have a day where my sodium is high, say 5000 mg, I know that i don't really have any issues with water retention staying within the default 2300, but i do retain once i start creeping up and up.. so.. back to 5000mg cause usually thats a typical number in sodium i hit when i over kill.. How many ml of water per mg of sodium would be good to drink to balance yourself? I am the type that retains water for at least 3-4 days after, if i drank this amount of water to restore balance, would that cut the amount of retention i experience down some, since i tend to pee pretty quickly after consuming liquids, Or would drinking enough water to balance out just cause issues?
Oh boy good question I don't know off the top of my head but I might look into that and try to respond. Off the top of my head I'd imagine the solution to the question is just to know the natural level of sodium that is considered balanced in your body and use that to figure out how much water.
The way it gets complicated is that water is required for lots of bodily functions not related to sodium like for digestion so not all the water you drink would be available for bringing the sodium to the desired concentration. So therefore whatever I'd calculate just off of the desired sodium concentration you'd probably need to drink more water than just that. How much more hard to say.
That said if you know how much water you need to drink when you have 2300mg sodium we should be able to calculate how much more water you'd need for 5000mg using that method. Just have to look up what the natural sodium concentration is in your body (ie weight of sodium per liter of water)
Okay I am at a computer now so I can look things up to try to give an answer. So here are the numbers I found that we need.
Here is my source: http://book.bionumbers.org/what-are-the-concentrations-of-different-ions-in-cells/
Okay so sodium in mammalian blood plasma is about 100 to 200 mM, lets call it 150mM. In comparison sea water is 500 mM. So your blood is really only about 3 times less salty than sea water. Not suprisingly when I looked up medical saline it looks like it is at a concentration of 154mM, which is right in line with the concentration in your blood https://en.wikipedia.org/wiki/Saline_(medicine). So if you are dehydrated and in a hospital they are going to hook you up to water that is only about 3 times less salty than sea water.
mM is a measure of concentration called millimolar. What 150mM of sodium means is that there are 150 milimoles per liter. A mole is a specific number of atoms. To convert that to weight we need to know the atomic weight of sodium which is on the periodic table and is 23 grams per mole which is the same as 23 miligrams per milimole. So what that means is 150 milimoles is the same as 150*23 = 3450 mg per liter. Wow, that is a ton isn't it. That is the amount of sodium in your blood right now. In comparison a liter of diet soda (that drink lots of people on here love to claim is high in sodium) has about 120mg in a liter...about 30 times less than what is in your blood. So yeah just a thought for people who claim soda is high in sodium. If you drink soda you are actually diluting the sodium concentration of your body, not increasing it.
Anyways, on to your question. You compared going from taking in 2300mg of sodium to taking in 5000mg. Lets pretend that the amount of food you eat is the same, its just much higher sodium content food. That would be an additional 2700mg of sodium. Given your blood has a concentration of 3450 mg per liter that would mean to take that 2700mg and put it at the same concentration that is in your blood you would only need to dissolve it in 780 mL of water. Call it an extra liter.
The reason though that we drink water and not salt water is because water is used for much more in our bodies than just solubilizing sodium so not all of the water you drink can be used to dilute out the sodium that you take in. All other variables held constant though yeah you'd only need to drink about an extra liter of water to hold that extra sodium in check...I think.
Haha, wow.. Thank you for taking the time for that, I will give that a try next time i sodium binge and let you know how long before i see my current weight again. Although i will probably just use tap water, those bottled waters are expensive enough as it is lol..
Oh, one more thing I should have mentioned. The amount of water I said, one liter, would be the amount needed to balance out the sodium...you'd retain all that water. If you wanted to start flushing sodium out of your body and decrease the amount of water you were retaining you'd want to drink much more than that. Like probably twice as much.
Ahh, okay, i will keep that in mind and maybe ill only need to wait a day or two instead of 4 or 50 -
@Aaron_K123 Is homeostasis in humans a very narrow range of saline concentrations or is homeostasis frequently observed to be amenable to life across a fairly wide range of saline concentrations? To put that in numerical terms, what's the median value and what's one standard deviation?0
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JeromeBarry1 wrote: »@Aaron_K123 Is homeostasis in humans a very narrow range of saline concentrations or is homeostasis frequently observed to be amenable to life across a fairly wide range of saline concentrations? To put that in numerical terms, what's the median value and what's one standard deviation?
@JeromeBarry1 Good question. Off the top of my head I don't know the answer to that although my immediate assumption is that it will be a pretty tight range. Much like pH or body temperature things that are homeostatically regulated in our bodies tend to be around values that are required biologically for our operation. Those tend to be pretty tightly controlled and pretty standard across all of humanity.
Although I don't know what the median and standard deviation is directly I imagine that the medical field can tell us something about it. If we then look up what it is to be high sodium or low sodium medically speaking that might give us an idea of the range.
Hyponatremia is the medical condition for having low sodium. It is apparently defined as sodium concentrations less than 135mM (https://en.wikipedia.org/wiki/Hyponatremia). Apparently getting below 120mM can cause seizures and coma.
Hypernatremia is high sodium levels. It is apparently defined as sodium concentrations above 145mM with severe cases being above 160mM (https://en.wikipedia.org/wiki/Hypernatremia)
So what that means is if you are below 135mM or above 145mM you are considered to have a medical problem, below 125mM or above 160mM and it is life threatening. I imagine that applies to all humans. So yeah it seems like it is very tightly regulated and it is a very narrow range. With that range I found it is a bit odd that medical saline is 154mM instead of 140mM, I'm sure there is a reason for that but I don't know it.
As for what the median and standard deviation of the current population is I don't know, I'd have to see if there have been any studies that have attempted to answer that. A quick google search revealed this study looking at sodium levels in 400 people (which I haven't read only skimmed)
https://watermark.silverchair.com/ajcpath21-0831.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAa4wggGqBgkqhkiG9w0BBwagggGbMIIBlwIBADCCAZAGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMN_bsSP5-rBtSZXuLAgEQgIIBYRFaxJTA3tuIYOzIGt9MlPWwigSsFM4XrE1FEUn6JalqWH2_e8t_puBGFAfEucytlWdXiHo9ltI4RDHHYQYv83I1QA3guMzycCODtGsYdA02MkWo4gTBnVMtjs_khHxsQx2g86Jt13KFv0jj3js96-ntQJWHgFrx166ZPatCq7OUOldS3sSpL1DBnhVPhbfchjir3UDSGjX_Bo4Gok_uZXxEsae3pnmIO2fWvlkUxUWTfdj95PD49pqiO7vDKrZC0bW2Hcw0NbIBXLh7jezOv0A9WKMSmK0cUFfsu85mYa0xi8H2aIELK7aHoJ_8n39iw58JTZu6VmRZhtCgBYugA_k12cYrXGFTtWsqzl8-cls4iXY3SCMqmjvlvbWOTM-rlJG5w3eG-nr164ooXGeoOVGtet3KWwIr5KRO8D4LcMdLufRU8SpwkfiIMIXPEucJhuQ4RBEtu1DeGpJZrYz3uhEm
They found the range to be 135 to 155 mM with a mean of 144.7mM and a standard deviation of 3.81mM with 70% falling within the mean +/- stDev.
Again that seems like a tight range so yeah both my assumptions and everything I looked up thusfar suggest that the range of sodium concentrations in human blood is quite narrow and doesn't range much.
Think of it like body temperature. Most people are 98.6 degrees within a narrow range. If your temp goes above 101 you are considered to have a fever, above 104 a high grade fever and if you get to something like 108 you are dead. That is pretty much true for all humans, I think sodium in your blood works the same way.
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So what that means is if you are below 135mM or above 145mM you are considered to have a medical problem, below 125mM or above 160mM and it is life threatening. I imagine that applies to all humans. So yeah it seems like it is very tightly regulated and it is a very narrow range. With that range I found it is a bit odd that medical saline is 154mM instead of 140mM, I'm sure there is a reason for that but I don't know it.
Figured out why medical saline is 154mM when blood sodium is 140mM on average. It is because medical saline is trying to mimic the overall osmolarity of blood plasma. Osmolarity is the total number of solute particles per liter deterimined by all disolved ions and solutes and although sodium is the major one in blood there are others. So although your blood likely has around 140mM of sodium it also has other dissolved ions which means its osmolarity is up around 154mM because I guess there are about 14 molar equivalents of other solutes in plasma. Rather than make a medical solution that has the exact amount of each of the hundreds of different solutes in blood plasma they just use sodium to get it to be the same osmolarity.
Osmolarity is what actually determines which way water would travel between two solutions seperated by a barrier that is permeable to water but not solutes. That is why it is important that what they put into you by IV has the same osmolarity as your blood, to avoid having pressure that would cause water to come either into or out of cells. In my original explanation I didn't get into that because it seemed overly detailed and sodium is the main factor in determining osmolarity in physiological solutions.
This is what I meant by saying my "technical" description is really also oversimplified.5 -
So if i drop 3 lbs overnight you’re saying its not fat that i lost?1
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Famof72015 wrote: »So if i drop 3 lbs overnight you’re saying its not fat that i lost?
Yeah you didn't lose 3 pounds of fat overnight, that isn't going to happen. Your body is made largely of water, it is quite easy for your body to shed or gain pounds of weight just from how much water your body happens to be retaining that day. Water retention can vary based on things like sodium intake, exercise (glycogen retention in muscles or DOMS) or your monthly cycle if you are a woman.
On any given day your bodyweight can easily change +/- 5 pounds just from changes in how much water you are retaining that day. To determine if you are losing fat you have to measure your weight over a long period of time and see if your average weight trends downward. Water weight fluctuates over an average, fat loss will cause your average weight to go down. Any given day though your weight can change a lot just from water so even if you are losing fat its quite possible you will measure yourself 5 days from now and be heavier than you are now just because you happen to be retaining more water that day. Don't let that fool you.7 -
Interesting bit of serendipity that you posted this the day before new guidelines on blood pressure were announced.7
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GottaBurnEmAll wrote: »Interesting bit of serendipity that you posted this the day before new guidelines on blood pressure were announced.
To be fair, the new guidelines simply redefine "pre-hypertension" to Stage 1 Hypertension. With little to no change in recommendations for care/treatment/correction... IOW diet/exercise/stress reduction.
Although I do like the idea of using a 24-48 hour monitor to determine actual hypertension because there are so many factors involved in getting a good reading.2 -
GottaBurnEmAll wrote: »Interesting bit of serendipity that you posted this the day before new guidelines on blood pressure were announced.
Oh? Wasn't aware. Say anything interesting?
Without looking at what they are I assume if it says anything about sodium it just says that if you have high blood pressure you should monitor your sodium intake according to doctors recommendations. I mean that is pretty much the one medical reason to care about sodium intake.0 -
Aaron_K123 wrote: »GottaBurnEmAll wrote: »Interesting bit of serendipity that you posted this the day before new guidelines on blood pressure were announced.
Oh? Wasn't aware. Say anything interesting?
Without looking at what they are I assume if it says anything about sodium it just says that if you have high blood pressure you should monitor your sodium intake according to doctors recommendations. I mean that is pretty much the one medical reason to care about sodium intake.
https://www.nytimes.com/2017/11/13/health/blood-pressure-treatment-guidelines.html0 -
I love stuff like this! And I finally realized why people with high blood pressure need to lower sodium. Thanks!0
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Hmm I looked up the American Heart Associations page on sodium and I have to say I am pretty dissapointed with them.
https://sodiumbreakup.heart.org/about_sodium?utm_source=SRI&utm_medium=HeartOrg&utm_term=Website&utm_content=SodiumAndSalt&utm_campaign=SodiumBreakup
They sound like a wellness blog just giving tips on ways to avoid sodium and making it sound like sodium is some toxic thing to be avoided at all costs...heck the top of their page is #breakupwithsalt. Buried in the page is one line "Almost everyone can benefit from cutting back on salt, because nearly all of us eat too much" which basically sums up their thinking. Everyone eats too much sodium so we are going to tell everyone it is important to eat less sodium. Not even going to attempt to explain sodium's effect just going to tell people to eat less sodium because chances are they are eating too much.
Thing is if you aren't eating too much or you are drinking plenty of water and balancing your sodium then this is not good advice. There is no mention anywhere on their pages I can find of the possibility that your sodium intake is fine or that you might actually be not getting enough sodium and what to do in those situations. I guess the idea is if you are going to their page you must have high blood pressure and therefore you must be taking in to much sodium.
Its like with blood pressure. High blood pressure isn't good for you. Low blood pressure isn't good for you either. High blood pressure is a much more common problem than low blood pressure so all of the media out there with regards to blood pressure focuses 100% on how to lower your blood pressure. Have you ever seen an article about how to raise your blood pressure? It gives the public the sense that the lower they can make it the better which just isn't true. I get the point of simplifying things so that everyone can follow along but it can be misleading.5 -
I was one of those that tried to lower sodium a lot - started using no-salt, don't salt a lot of foods that normally would be. High blood pressure runs in my family, so I didn't want to get it, so thought if I could eliminate a lot of salt, that would be good. I actually have been using a little more salt since joining here. Threw out the No-salt and bought real salt. I drink quite a bit of liquid a day to keep kidney infections away, so realized I probably need more. And my blood pressure was 115/68 last time it was taken, so I try to just keep it at the daily recommended level now.
Posts like yours, Aaron, are really helpful in understanding how and why. I hope you continue!2 -
Great post. I'm interested in salt and thirst. I've always assumed that eating salty foods makes you thirsty, but is that true?0
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Okay going to go into even more detail just to clarify a point here so bear with me. I left this detail out of my first post. First we need to define osmolarity.
Osmolarity is the number of moles of dissolved solutes in one liter. A solute is just a molecule that is solubilized in a liquid. If two solutions with the same osmolarity are separated by a water permeable barrier nothing will happen. If one solution has a higher osmolarity than the other solution then water will transfer from the low osmolarity solution to the high osmolarity solution until their osmolarities are equal. You can think of this force as a pressure between the two solutions.
If you take a living human cell, which is a bag of water full of dissolved solutes, and you put it into pure water then the osmolarity of the contents of the cell are much much higher than the surrounding water you put it in so water will rush into the cell. There is enough pressure in the difference between the osmolarities of a cell and pure water that water will rush into the cell so much that the cell will literally pop and die.
In your body therefore the liquid surrounding your cells including your blood needs to have basically the same osmolarity (the same amount of dissolved stuff) as what is within your cells. It doesn't have to be the same stuff, just the same total amount of stuff.
If a hospital hooked you up to an IV full of pure water it would actually kill you. Instead they use saline. The saline solution has enough dissolved solutes in the form of sodium and chloride (salt) that it is the same osmolarity as your cells. It is okay to drink pure water because that water is then combined with stuff in your digestive track before it migrates into your body or that water is just absorbed and flushed out of you if it isn't needed to dissolve things.
One interesting property of osmolarity is it doesn't matter how big the dissolved solutes are. If you had 100 dissolved glucose molecules (C6H12O6) in a solution it would have the same osmolarity as a solution that had 100 dissolved sodium ions in it (Na+) even though glucose is a much larger molecule than sodium which is just a single atom. Since salt is NaCl and in water NaCl breaks apart into 1 Na+ and 1 Cl+ that means 100 molecules of salt turn into 200 dissolved solutes. So 1 M salt would have an osmolarity of 2 M. Not only that but salt is literally just two atoms and it seperates into single atoms so it doesn't take very many grams of salt to equal a mole where it would take many more grams of glucose to equal a mole and glucose is a small molecule. So salt has a huge bang-for-buck in terms of osmolarity.
So picture a cell, it has a ton of different molecules in it: sugars, fats, proteins etc etc. If you counted up each dissolved molecule in the water in the cell and divided that by the total water volume in the cell that would be the cells osmolarity. If you then take pure water and add enough salt to it that the number of sodium and chloride ions in that water equal the number of total dissolved solutes inside the cell and then you place the cell into that water then they will be in balance...water will neither rush out of or rush into the cell. Turns out for our body that is about 154mM of sodium (which also has 154mM of chloride or other negative ion in it) which would be an osmolarity of 308mM.
Your blood has the same osmolarity as your cells. Most of that osmolarity comes from salt and since salt is NaCl and there is always 1 chloride for 1 sodium it is easier to just track the one ion which is sodium.
So the sodium levels in your blood basically determine its osmolarity. It is critical the osmolarity of you blood remain the same as your cells to prevent water rushing into or out of your cells. As such your body regulates the osmolarity of your blood by either diluting it with more water or adding more sodium.
I found this video that explains the basic concept of osmolarity well https://www.youtube.com/watch?v=_saunfB-wCQ
One of osmolarity of our own blood plasma. He comes up with a value of 290 mM which is close to the 308mM of saline. https://www.youtube.com/watch?v=H-qREcJqUhY6 -
JoLightensUp wrote: »Great post. I'm interested in salt and thirst. I've always assumed that eating salty foods makes you thirsty, but is that true?
Well I'm not sure how "thirst" works from a biological perspective (ie what triggers you to feel thirsty) but it does make logical since that if you eat a lot of salt your body would benefit from you drinking a lot of water and therefore might have some sort of cue to trigger your thirst on the basis of how much salt you have taken in. I just don't know if that actually happens.
There are plenty of examples where there is no biological "trigger" for doing an action that would benefit us. An example of this I can think of is the desire to breath. The urge to take a breath can be unbearably strong. You might think your body needs oxygen so when you don't have enough oxygen your body will scream at you to breath....but that isn't actually the trigger. The trigger for wanting to breath is a lot of carbon dioxide has built up in your blood and your body screams at you to exhale it. Your body monitors that carbon dioxide level, it doesn't monitor oxygen levels.
If you walked into a room that was 100% filled with helium gas and breathed normally your body wouldn't be getting enough oxygen as you breathed in helium and breathed out carbon dioxide. You wouldn't build up carbon dioxide though since you'd still be exhaling so you wouldn't sense that anything was wrong. You wouldn't feel deprived, you wouldn't gasp for air you would go about your business until oxygen reached a critically low level in your body at which point you would pass out and then die completely painlessly and with no warning.
So long story short biological "triggers" to do things aren't always necessarily logical in that way. It makes sense that you should drink water if you eat salt but I don't know if that "triggers" your thirst or not.9 -
Aaron_K123 wrote: »JoLightensUp wrote: »Great post. I'm interested in salt and thirst. I've always assumed that eating salty foods makes you thirsty, but is that true?
Well I'm not sure how "thirst" works from a biological perspective (ie what triggers you to feel thirsty) but it does make logical since that if you eat a lot of salt your body would benefit from you drinking a lot of water and therefore might have some sort of cue to trigger your thirst on the basis of how much salt you have taken in. I just don't know if that actually happens.
There are plenty of examples where there is no biological "trigger" for doing an action that would benefit us. An example of this I can think of is the desire to breath. The urge to take a breath can be unbearably strong. You might think your body needs oxygen so when you don't have enough oxygen your body will scream at you to breath....but that isn't actually the trigger. The trigger for wanting to breath is a lot of carbon dioxide has built up in your blood and your body screams at you to exhale it. Your body monitors that carbon dioxide level, it doesn't monitor oxygen levels.
If you walked into a room that was 100% filled with helium gas and breathed normally your body wouldn't be getting enough oxygen as you breathed in helium and breathed out carbon dioxide. You wouldn't build up carbon dioxide though since you'd still be exhaling so you wouldn't sense that anything was wrong. You wouldn't feel deprived, you wouldn't gasp for air you would go about your business until oxygen reached a critically low level in your body at which point you would pass out and then die completely painlessly and with no warning.
So long story short biological "triggers" to do things aren't always necessarily logical in that way. It makes sense that you should drink water if you eat salt but I don't know if that "triggers" your thirst or not.
Interesting. Thanks. Your initial post got me thinking about whether thirst drives might be altered for those who were accustomed to a salty diet. I will have to go and do some reading as I am now curious about how that all works!0 -
Great information. Thanks for sharing.0
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@Tariq_1997 -- to answer your salt question0
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Aaron_K123 wrote: »Aaron_K123 wrote: »I have thought about doing this on the regular, that is why I made the title I did "Biochemistry answers for common weight loss questions: Sodium" so that if it is popular at all or people find it useful I might do another that is "Biochemistry answers for common weight loss questions: XXXX" for another topic, probably answering where your weight actually goes when you lose weight. Don't want to commit just yet though, not sure if this sort of long-winded technical description is something people actually want. If it stays up for a while or gets a lot of discussion I might do another.BrookeLynn18 wrote: »I would really enjoy this!
I'd have fun writing others if people are interested. Biochem or molecular bio perspective on weight loss or myths/misconceptions associated with weight loss. Not sure if forum posts are the right format or a blog, or maybe some sort of sticky area if that is of interest to the moderators/admins and people would like it (not to sound overly arrogant just a thought)
I don't find your posts arrogant at all.
I learn from them and that can only be a good thing. Keep posting them.
I'd personally love you to post one on the relationship between magnesium, potassium and sodium balancing. I've been curious about it since I took part in the 800g a day fruit and veg challenge.
2 -
Aaron_K123 wrote: »One interesting property of osmolarity is it doesn't matter how big the dissolved solutes are. If you had 100 dissolved glucose molecules (C6H12O6) in a solution it would have the same osmolarity as a solution that had 100 dissolved sodium ions in it (Na+) even though glucose is a much larger molecule than sodium which is just a single atom. Since salt is NaCl and in water NaCl breaks apart into 1 Na+ and 1 Cl+ that means 100 molecules of salt turn into 200 dissolved solutes. So 1 M salt would have an osmolarity of 2 M. Not only that but salt is literally just two atoms and it seperates into single atoms so it doesn't take very many grams of salt to equal a mole where it would take many more grams of glucose to equal a mole and glucose is a small molecule. So salt has a huge bang-for-buck in terms of osmolarity.
Minor nitpick. I'm pretty sure the above is not correct from a chemistry perspective.
That may happen in the body, but it takes more than just water.
0 -
stanmann571 wrote: »Aaron_K123 wrote: »One interesting property of osmolarity is it doesn't matter how big the dissolved solutes are. If you had 100 dissolved glucose molecules (C6H12O6) in a solution it would have the same osmolarity as a solution that had 100 dissolved sodium ions in it (Na+) even though glucose is a much larger molecule than sodium which is just a single atom. Since salt is NaCl and in water NaCl breaks apart into 1 Na+ and 1 Cl+ that means 100 molecules of salt turn into 200 dissolved solutes. So 1 M salt would have an osmolarity of 2 M. Not only that but salt is literally just two atoms and it seperates into single atoms so it doesn't take very many grams of salt to equal a mole where it would take many more grams of glucose to equal a mole and glucose is a small molecule. So salt has a huge bang-for-buck in terms of osmolarity.
Minor nitpick. I'm pretty sure the above is not correct from a chemistry perspective.
That may happen in the body, but it takes more than just water.
I disagree I believe my statement is correct as written. NaCl is ionic (the atoms are connected by an ionic bond not a covalent bond) and it does disassociate into Na+ and Cl- in water. This process is not biological in nature, its physics, it doesn't require a body to happen. If you have some information to suggest otherwise I'd be interested in seeing it but I'm confident that what I said is correct. 1 mole of NaCl put into 1 liter of water would have an osmolarity of 2 due to that dissaociation. Posted a video earlier about osmolarity and in it there is an example of NaCl.
The reason ionic substances dissolute in water is because using NaCl as an example the Na and Cl atoms are not covalently bonded to one another, they stick to one another because sodium (Na+) is positively charged while chloride (Cl-) is negatively charged and the opposite charged attract eachother. Thing is water molecules have slight charge as well. The oxygen atom in water is a lot more electronegative than the hydrogens and attracts the hydrogens sole electron closer to the oxygen atom. This causes what is known as a dipole moment whereby the oxygen is partially negatively charged and the hydrogens partially positive charged. That means the sodium atom will also attract to the oxygen in water while the chlorides will attract to the hydrogens. As there are a lot more water molecules than Na and Cl molecules they end up surrounding them to make multiple contacts. This interaction ends up pulling the sodium and chloride atoms apart.
https://www.youtube.com/watch?v=EBfGcTAJF4o
That is just a result of the interaction of charge from physics, nothing biological about it. It also happens with any ionic bond. Polar solvents (like water) dissolve molecules that are connected through ionic bonds.
In contrast the atoms in a glucose molecule are all covalently bound to one another and will not dissassociate in a polar solvent like water. As a result 1 mole of glucose in 1 liter of water has an osmolarity of 1.5 -
Aaron_K123 wrote: »stanmann571 wrote: »Aaron_K123 wrote: »One interesting property of osmolarity is it doesn't matter how big the dissolved solutes are. If you had 100 dissolved glucose molecules (C6H12O6) in a solution it would have the same osmolarity as a solution that had 100 dissolved sodium ions in it (Na+) even though glucose is a much larger molecule than sodium which is just a single atom. Since salt is NaCl and in water NaCl breaks apart into 1 Na+ and 1 Cl+ that means 100 molecules of salt turn into 200 dissolved solutes. So 1 M salt would have an osmolarity of 2 M. Not only that but salt is literally just two atoms and it seperates into single atoms so it doesn't take very many grams of salt to equal a mole where it would take many more grams of glucose to equal a mole and glucose is a small molecule. So salt has a huge bang-for-buck in terms of osmolarity.
Minor nitpick. I'm pretty sure the above is not correct from a chemistry perspective.
That may happen in the body, but it takes more than just water.
I disagree I believe my statement is correct as written. NaCl is ionic (the atoms are connected by an ionic bond not a covalent bond) and it does disassociate into Na+ and Cl- in water. This process is not biological in nature, its physics, it doesn't require a body to happen. If you have some information to suggest otherwise I'd be interested in seeing it but I'm confident that what I said is correct. 1 mole of NaCl put into 1 liter of water would have an osmolarity of 2 due to that dissaociation. Posted a video earlier about osmolarity and in it there is an example of NaCl.
The reason ionic substances dissolute in water is because using NaCl as an example the Na and Cl atoms are not covalently bonded to one another, they stick to one another because sodium (Na+) is positively charged while chloride (Cl-) is negatively charged and the opposite charged attract eachother. Thing is water molecules have slight charge as well. The oxygen atom in water is a lot more electronegative than the hydrogens and attracts the hydrogens sole electron closer to the oxygen atom. This causes what is known as a dipole moment whereby the oxygen is partially negatively charged and the hydrogens partially positive charged. That means the sodium atom will also attract to the oxygen in water while the chlorides will attract to the hydrogens. As there are a lot more water molecules than Na and Cl molecules they end up surrounding them to make multiple contacts. This interaction ends up pulling the sodium and chloride atoms apart.
https://www.youtube.com/watch?v=EBfGcTAJF4o
That is just a result of the interaction of charge from physics, nothing biological about it. It also happens with any ionic bond. Polar solvents (like water) dissolve molecules that are connected through ionic bonds.
IF that was true, then boiling salt water would leave sodium instead of salt.1 -
stanmann571 wrote: »Aaron_K123 wrote: »stanmann571 wrote: »Aaron_K123 wrote: »One interesting property of osmolarity is it doesn't matter how big the dissolved solutes are. If you had 100 dissolved glucose molecules (C6H12O6) in a solution it would have the same osmolarity as a solution that had 100 dissolved sodium ions in it (Na+) even though glucose is a much larger molecule than sodium which is just a single atom. Since salt is NaCl and in water NaCl breaks apart into 1 Na+ and 1 Cl+ that means 100 molecules of salt turn into 200 dissolved solutes. So 1 M salt would have an osmolarity of 2 M. Not only that but salt is literally just two atoms and it seperates into single atoms so it doesn't take very many grams of salt to equal a mole where it would take many more grams of glucose to equal a mole and glucose is a small molecule. So salt has a huge bang-for-buck in terms of osmolarity.
Minor nitpick. I'm pretty sure the above is not correct from a chemistry perspective.
That may happen in the body, but it takes more than just water.
I disagree I believe my statement is correct as written. NaCl is ionic (the atoms are connected by an ionic bond not a covalent bond) and it does disassociate into Na+ and Cl- in water. This process is not biological in nature, its physics, it doesn't require a body to happen. If you have some information to suggest otherwise I'd be interested in seeing it but I'm confident that what I said is correct. 1 mole of NaCl put into 1 liter of water would have an osmolarity of 2 due to that dissaociation. Posted a video earlier about osmolarity and in it there is an example of NaCl.
The reason ionic substances dissolute in water is because using NaCl as an example the Na and Cl atoms are not covalently bonded to one another, they stick to one another because sodium (Na+) is positively charged while chloride (Cl-) is negatively charged and the opposite charged attract eachother. Thing is water molecules have slight charge as well. The oxygen atom in water is a lot more electronegative than the hydrogens and attracts the hydrogens sole electron closer to the oxygen atom. This causes what is known as a dipole moment whereby the oxygen is partially negatively charged and the hydrogens partially positive charged. That means the sodium atom will also attract to the oxygen in water while the chlorides will attract to the hydrogens. As there are a lot more water molecules than Na and Cl molecules they end up surrounding them to make multiple contacts. This interaction ends up pulling the sodium and chloride atoms apart.
https://www.youtube.com/watch?v=EBfGcTAJF4o
That is just a result of the interaction of charge from physics, nothing biological about it. It also happens with any ionic bond. Polar solvents (like water) dissolve molecules that are connected through ionic bonds.
IF that was true, then boiling salt water would leave sodium instead of salt.
No...it wouldn't. As you boil the water the water molecules vaporize into a gas leaving the solution and going into the air. Sodium and chloride do not vaporize and remain behind. As the water molecules depart the amount of water molecules versus sodium and chloride molecules decreases over time and the attractive forces between the positively charged sodium and the negatively charged chloride ions begin to dominate and they once again attract one another reforming an ionically bonded NaCl crystal. Again this isn't specific to table salt, it would be true of any ionically bonded molecule in any polar solvent.
Another way to think of this is that water will only dissolve salt when there are considerably more water molecules than salt molecules. Once you get to the point where there is too much salt it will stop dissolving. Water won't dissolve an infinite amount of salt. If you pour salt into a cup of water and stir and you keep pouring in salt eventually it will stop dissolving. So, when you boil water, what you are effectively doing is decreasing the amount of water available to solubilize the dissolved salt...as a result the salt reforms.7 -
Aaron_K123 wrote: »stanmann571 wrote: »Aaron_K123 wrote: »stanmann571 wrote: »Aaron_K123 wrote: »One interesting property of osmolarity is it doesn't matter how big the dissolved solutes are. If you had 100 dissolved glucose molecules (C6H12O6) in a solution it would have the same osmolarity as a solution that had 100 dissolved sodium ions in it (Na+) even though glucose is a much larger molecule than sodium which is just a single atom. Since salt is NaCl and in water NaCl breaks apart into 1 Na+ and 1 Cl+ that means 100 molecules of salt turn into 200 dissolved solutes. So 1 M salt would have an osmolarity of 2 M. Not only that but salt is literally just two atoms and it seperates into single atoms so it doesn't take very many grams of salt to equal a mole where it would take many more grams of glucose to equal a mole and glucose is a small molecule. So salt has a huge bang-for-buck in terms of osmolarity.
Minor nitpick. I'm pretty sure the above is not correct from a chemistry perspective.
That may happen in the body, but it takes more than just water.
I disagree I believe my statement is correct as written. NaCl is ionic (the atoms are connected by an ionic bond not a covalent bond) and it does disassociate into Na+ and Cl- in water. This process is not biological in nature, its physics, it doesn't require a body to happen. If you have some information to suggest otherwise I'd be interested in seeing it but I'm confident that what I said is correct. 1 mole of NaCl put into 1 liter of water would have an osmolarity of 2 due to that dissaociation. Posted a video earlier about osmolarity and in it there is an example of NaCl.
The reason ionic substances dissolute in water is because using NaCl as an example the Na and Cl atoms are not covalently bonded to one another, they stick to one another because sodium (Na+) is positively charged while chloride (Cl-) is negatively charged and the opposite charged attract eachother. Thing is water molecules have slight charge as well. The oxygen atom in water is a lot more electronegative than the hydrogens and attracts the hydrogens sole electron closer to the oxygen atom. This causes what is known as a dipole moment whereby the oxygen is partially negatively charged and the hydrogens partially positive charged. That means the sodium atom will also attract to the oxygen in water while the chlorides will attract to the hydrogens. As there are a lot more water molecules than Na and Cl molecules they end up surrounding them to make multiple contacts. This interaction ends up pulling the sodium and chloride atoms apart.
https://www.youtube.com/watch?v=EBfGcTAJF4o
That is just a result of the interaction of charge from physics, nothing biological about it. It also happens with any ionic bond. Polar solvents (like water) dissolve molecules that are connected through ionic bonds.
IF that was true, then boiling salt water would leave sodium instead of salt.
No...it wouldn't. As you boil the water the water molecules vaporize into a gas leaving the solution and going into the air. Sodium and chloride do not vaporize and remain behind. As the water molecules depart the amount of water molecules versus sodium and chloride molecules decreases over time and the attractive forces between the positively charged sodium and the negatively charged chloride ions begin to dominate and they once again attract one another reforming an ionically bonded NaCl crystal. Again this isn't specific to table salt, it would be true of any ionically bonded molecule in any polar solvent.
Sodium is a reactive metal, chlorine is a gas.
Google agrees with you, but it still doesn't make sense.2
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