K-citrate (K=potassium) for bone loss:
- Studies with 90 mmol per day of K-citrate supplementation show that it could reverse osteoporosis.
- Studies using 60 mmol per day have diverse effects, some look good for osteoporosis, some not.
- Studies using less than 60 mmol per day of K-citrate supplementation usually show no benefit on bones.
Units:
Molar mass of K-citrate = 306.4 g/mol. So 90 mmol is 0.090x306.4 = 27.6 g K-citrate
Bulk K-citrate powder weighs about 5.9 g/tsp. It is slightly hydroscopic, so the K-citrate part is about 5.5 g/tsp.
90 mmol/d of K-citrate = 27.6g/5.5g = 5.0 tsp/d of pure K-citrate powder.
1 molecule of K-citrate has 3 atoms of K. So 90 mmol of K-citrate has 270 mmol of K atoms.
Atomic mass of K = 39.1 g/mol. So 90 mmol of K-citrate has 270/39.1 = 6.9 g K atoms
For comparison, typical US intake of K atoms is about 2.7 g/d. Adding dietary K gives 6.9+2.7 = 9.6 g/d of K atoms. RDA is 4.7 g/d
Theory:
The theory is that the calcium that is needed to buffer blood pH is taken from the bones and lost in the urine when urine is acidic, and that is prevented by alkaline urine.
From personal experience, 60 mmol per day is marginal to alkalinize urine, where 90 mmol per day alkalinizes it quite well. [Tested by watching the color when a drop of General Hydroponics pH indicator hits the toilet. green=alkaline red=acidic]
At least 1 epidemiological study based on diet questionnaires found that a less acidic diet corresponded to less osteoporosis. Another placebo controlled study that lasted 2 yr did not detect a difference based on diet alone. My take: with dietary means alone, urine can be a little less acidic, but is not likely to shift all the way to alkaline.
Mg-acetate for alkaline urine:
90 mmol per day (5 tsp/d) of K-citrate powder will quickly kill you if your kidneys aren't working right.
Even with good kidneys, I did not feel comfortable taking 5 tsp/d of K-citrate. I found an alternate that works even better. I add 15 tbsp of clear Mg-acetate solution containing 1.8 g of Mg & 15.7 g of acetate to my 1.5L water pitcher. Then I throw in 1 tsp of K-citrate powder (2.5 g of K), and 1 tsp of MSM powder (for joints). This is very alkalinizing. The pH drops in the toilet turn bright green all day. Mg-acetate solution is made by mixing 1 tbsp MOM (milk of magnesia) and 12 tbsp of white vinegar. After a mild exothermic reaction, the cloudy mixture turns clear.
I will have a new bone scan a year from now, and compare to the scan from a year ago. Meanwhile, my bisphosphonate prescription is sitting on the shelf while I see if this works.
(1) Increased BMD shown with 90 mmol/d of K-citrate - study lasted 2 yrs.
https://www.ncbi.nlm...les/PMC3578058/ "Potassium citrate supplementation results in sustained improvement in calcium balance in older men and women" Journal of Bone and Mineral Research, Mar 2013 (52 men & women studied, half given placebo)
(2) Positive calcium balance shown with 90 mmol/d of K-citrate - 1 mo lab study
https://www.ncbi.nlm...pubmed/11994333 "Potassium citrate prevents increased urine calcium excretion and bone resorption induced by a high sodium chloride diet" The Journal of Clinical Endocrinology & Metabolism, May 2002. (After 1 mo of increased salt intake, the K-citrate group's calcium balance shifted to positive. The control group's calcium balance shifted further negative.)
(3) Positive results with 60 mEq of K-citrate - 2 yr study (Note: 60 mEq is 60 mmol for K-citrate)
https://www.ncbi.nlm...pubmed/23162100 "Effect of potassium citrate on bone density, microarchitecture, and fracture risk in healthy older adults without osteoporosis: a randomized controlled trial" The Journal of Clinical Endocrinology & Metabolism, Jan 2013. 201 older adults (age > 60) were studied for 24 mo "
Our results suggest that treatment with an alkaline salt, such as potassium citrate, can reduce bone resorption"
(4) Positive resuts for about 1 tsp of "K-citrate" (18 mmol) - possibly a typo on the dosage
https://www.ncbi.nlm...pubmed/15255069 "Effects of potassium citrate supplementation on bone metabolism." Calcified Tissue International, Apr 2004. "
Our results suggest that treatment with an alkaline salt, such as potassium citrate, can reduce bone resorption .." According to the article they only gave 0.1 g/kg of "K-citrate" - about 1 tsp/d of K-citrate for a 120 lb woman. The results are more consistent with 0.1 g/kg of "K" - about 5 tsp of K-citrate for a 120 lb woman (about 90 mmol/d).
Edited by RWhigham, 11 December 2016 - 12:10 AM.
