Potassium,Testosterone & Muscle

Summary

Animal studies show deficiency in potassium (chemical symbol K) causes dramatic decreases in plasma testosterone. If these results apply to humans, which I strongly suspect they do, this is a problem for most men. Potassium deficiency is extremely common. My personal experience suggests that increasing potassium intake makes my voice deeper, provided I'm taking sufficient amounts of other minerals, such as magnesium and zinc. The animal research suggests that potassium deficiency lowers Luteinizing Hormone (LH), but in a way that is related to the production of some factor (other than testosterone) in the testes. The researchers suspect that this unknown factor is inhibin although that suspicion remains unconfirmed.

Other animal research suggests potassium deficiency reduces growth hormone and muscle growth.

Animal research - Potassium Deficiency & Testosterone

Mouse study: Potassium deficiency leads to dramatic decrease in plasma testosterone
https://www.ncbi.nlm.nih.gov/pubmed/8224166
Design/Methods: RCT. Mice were divided into three groups one fed deficiency diet for 30 days, one control diet for 30 days, and one a deficiency diet for 15 day followed by another 15 days involving potassium replenishment. The study also looked at both male and female mice and was primarily designed to look at kidney function, with a secondary focus on testosterone. For this write up, we'll focus on the male mice and the findings related to testosterone.
Subjects: Adult Swiss CD1 mice
Feed: Control - standard chow (UAR A03) containing 7500 mg per kg potassium. Deficiency - similar diet but containing 120 mg/kg potassium (UAR 212K). Replenishment - water was replaced with a 1% Potassium Chloride solution.
Duration: 30 days. Measures taken at 15 and 30 days.
Findings:The results really were dramatic. In the control group testosterone was 48.9 nM compared to just 2.9 nM in potassium deficient group. Upon potassium replenishment, testosterone lept to 67.3 nM.
Omissions: The study did not look at estrogen, LH, FSH, dihydrotestosterone (DHT), sex hormone binding globulin (SHGB), inhibin, activin

Potassium_Testosterone2.png

Mouse study: Potassium deficiency decreases testosterone by decreasing lutenizing hormone via a testicular signal.
http://www.ncbi.nlm.nih.gov/pubmed/8756540
Subjects: Male adult Swiss CD1 mice.
Feed: Control - standard chow (UAR A03) containing 7500 mg per kg potassium. Deficiency - similar diet but containing 120 mg/kg potassium (UAR 212K). Replenishment - water was replaced with a 1% Potassium Chloride solution.
Summary: The study was designed to look at how potassium deficiency caused a dramatic drop in testosterone. Firstly, the mice were made potassium deficient, a dramatic drop in testosterone was found both in the testes and the serum. In the potassium deficient mice, it was also noted that luteinizing hormone (LH) was decreased. LH is the hormone produced in the pituitary gland in the brain that stimulates the leydig cells in the testicles to produce testosterone. Furthermore, when LH was administered to the rats, the testicles produced testosterone as normal, suggesting that potassium deficiency was not affecting the ability of the leydig cells to produce testosterone, it was simply that they were receiving a much lower LH signal. However, when the mice were castrated (orchidectomy), LH levels normalized. This suggests that potassium deficiency led to some unknown factor in the testes feeding back to the pituitary that was suppressing LH production. The researchers suspect that inhibin is a possible culprit.

Human studies - Who is deficient in potassium? Almost everyone

If you are potassium deficient, be worried! And what's worth… you probably are potassium deficient! This study found that every single person they sampled was deficient in potassium http://www.ncbi.nlm.nih.gov/pubmed/24724766

Also, keep in mind that potassium requires magnesium!

Potassium, Growth Hormone, Protein Synthesis and Muscle

Rat study: Potassium deficiency reduces growth, growth hormone and IGF-1
https://www.ncbi.nlm.nih.gov/pubmed/1861625
Subjects: Young (4 1/2 week old) rats
Findings: 10 days on a potassium deficient diet reduced serum potassium by 54%. This was accompanied by a weight gain reduction of 97% compared to control rats. Muscle weight was also reduced. Insulin showed no decreased, however, there was a reduction in IGF-1 by 46%. Growth hormone was reduced too. Hormone levels and weight gain rebounded upon potassium replenishment.

Rat study: Potassium deficiency reduces growth and protein synthesis
https://www.ncbi.nlm.nih.gov/pubmed/2819012
Subjects: Young (4-13 week old) rats
Key Findings: Potassium deficiency caused the rats to cease to grow within a few days. Incorporation of radio-labeled leucine into skeletal muscle was reduced by 28-38%. Following potassium replenishment incorporation returned to normal after 72 hours.

Body Temperature

Mouse Study: Potassium deficiency reduces body temperature
http://www.sciencedirect.com/science/article/pii/S0306456599000893
Potassium deficiency reduces body temperature.

Narrative Review: Evolving Concepts in Potassium Homeostasis and Hypokalemia
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4944758/

LH release stimulated by LH-RH is much less dependent upon the availability of extracellular Ca2+ than that stimulated by either high K+ or A-23187.
https://www.ncbi.nlm.nih.gov/pubmed/103759