Nice! I Sharpie’d ours.
The experience with Lumen is really great, in the morning I get a suggestion about how much carbohydrates, protein and fats I should eat,
in the meantime I’ve made a set of meals to organize the things better to reach the suggestions.
If I don’t have enough carbohydrates before a workout, Lumen tells me to make improvements, I can handle hard workouts so much better!
they have a very good customer support, they contacted me, because the seen something goes wrong with my first device, they sent me a replacement very fast.
At the beginning my carb suggestions was to low and the fat to high, but they changed it in the background (Nutrition Expert Ulrike), now i eat exactly as much as i need for my workouts (Duathlon) and my body weight is very stable too and my performance increases from week to week
Very interesting . Thanks
Thanks. Just bought some sodium citrate (trisodium citrate Na3C6H5O7) and did the math using molecular weights and density. Posting for future reference:
- 1 teaspoon = 4.93 ml
- Sodium citrate is 1.008 g/ml
- 4.969 grams of sodium citrate per teaspoon (4.93 x 1.008)
- using molecular weights of sodium citrate and 3 sodium atoms, by weight the sodium is 26.7% of sodium citrate
- 1326mg of sodium in 1 teaspoon (4.93 x 1.008 x .267)
hope that helps anyone interested. And someone correct me if my high school chemistry failed me!
This label found on Modernist Pantry:
puts Sodium at 235mg per gram of Sodium Citrate. Using 1 teaspoon = 4.969g from above, that puts sodium at 1168mg per teaspoon.
So three estimates per teaspoon:
- 1000mg rough estimate
- 1326mg from density and molecular weights
- 1168mg from a label
close enough!
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I’m skeptical (unless you bought the sodium citrate from their catalog) a volumetric measure for a powder is going to depend on how the crystal is formed/ground. I’m thinking of differences between brands of salt: Morton’s kosher salt vs table-salt vs diamond crystal (light and fluffy).
Anybody have access to CRC Handbook of Chemistry and Physics? I sold mine and only have the CRC Math Handbook on the shelf.
My calculation above is also off, I used molar mass of 258.06 g/mol which is true for anhydrous but I believe the correct value is 294.10 g/mol for dihydrate version of trisodium citrate. So that would change the percentage to 23.5% …
- 1 teaspoon = 4.93 ml
- Sodium citrate is 1.008 g/ml
- 4.969 grams of sodium citrate per teaspoon (4.93 x 1.008)
- using molecular weights of sodium citrate and 3 sodium atoms, by weight the sodium is 23.45% of sodium citrate (3 x 22.989 / 294.10)
- 1165mg of sodium in 1 teaspoon (4.93 x 1.008 x .2345)
ignoring granularity for example Cargill specs 60lbs/cubic-foot for granular and 58 lbs/cubic-foot for fine granular (the stuff I bought on Amazon looks to be fine granular).
Which bringing this back full circle the three estimates per teaspoon are:
- 1000mg rough estimate
- 1165mg from density and molecular weights of trisodium citrate dihydrate
- 1168mg from a label
When operating in non-medical biology, and especially with electrolytes, rough estimates will do just fine.
VERY much appreciate the lengths you went to to come up with accurate numbers.
Carbohydrate accuracy is likely to be much more important than sodium measurement accuracy, and even for carbs, I don’t sweat it. (terrible-pun intended).
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Yeah, I’m not sweating the details. Just wanted to understand where the estimates came from, and have a chance to revisit two years of high school chemistry LOL.
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PS. I’ve been waiting for the day someone calls me out on these super-round numbers I’ve been using 
Honestly, I’m surprised it took this long! Our resident chemical engineer, @redlude97, got close to doing so in another thread, I think.
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nice! you da man
I’m a little confused about the updated calc using density of anhydrous and molecular weight of dihydrous, but I’m good with rough estimates. It’s not like I actually know my sodium loss from sweating. 
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And another label:
1400mg for 1 teaspoon
Five estimates per teaspoon are:
- 1000mg rough estimate
- 1326mg from trisodium citrate data using anhydrous density and anhydrous molecular weight
- 1400 mg from Judee’s Sodium Citrate label
- 1165mg from trisodium citrate with anhydrous density and dihydrate molecular weight
- 1168mg from Modernist Pantry label
Calling @redlude97 to review! 
Not a big deal, just curious.
Yesterday I opened the Pure Ingredients branded sodium citrate, added one teaspoon to a water bottle an hour before going out in 102F / 39C heat. Looking closely at Precision Hydration and recalled that info is confusing. One packet of PH1500 is roughly 750mg sodium, 125mg potassium, 24mg calcium, and 12mg magnesium.
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hopefully you will give me partial credit for showing my work, like they did in most of my engineering classes 
Go easy on me LOL, I’m dealing with a lot of parental unit stress (getting old sucks in more than one way).
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Glad to see someone else wondering about hydrated vs anhydrous - I’m almost out of my sodium bicarb based electrolyte mix and working on my next batch with sodium citrate
I have found with my bicarb based mix that it helps a lot to keep a desiccant package in the jar as otherwise it clumps up.
Breaking up the clumps in my new bag today:
Pro tip: use metal utensils. Showed my wife and apparently a couple years ago “someone else” (before kids left the house) broke it, and she glued it back together.
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Weird. I’ve never had any clumping whatsoever with that stuff and am on our 4th bag of it.
Now… beet root powder, that turns to solid rock eventually. Need industrial tools to break before scooping.
A couple pea size and one larger one. Could have massaged the bag and gotten rid of it.
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good idea. Finally found our scale and its definitely trisodium citrate anhydrous with density of 1.008 g/ml (and not the heavier dihydrate).
updating my calculations for Pure Ingredients brand Sodium Citrate (trisodium citrate anhydrous)
- 1 teaspoon = 4.93 ml
- trisodium citrate anydrous is 1.008 g/ml
- 4.969 grams per teaspoon (4.93 x 1.008)
- using molecular weights of trisodium citrate anhydrous and 3 sodium atoms, by weight the sodium is 26.7% of sodium citrate (3 x 22.989 / 258.07)
- 1327mg of sodium in 1 teaspoon (4.93 x 1.008 x .267)
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After a week or so of using sodium citrate, I can barely taste 1 teaspoon / 1300mg of sodium in a 22 ounce Podium insulted bottle with ice water. Temps lately have been 90-100F. For training rides I don’t put carbs in my water bottles.
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