Do you know how mag & potassium help?
Yes. Your body cannot manufacture, distribute, or absorb D from sunlight or supplements without there being sufficient magnesium in the body at the same time. So a D supplement taken when you are low in mag would just be excreted. This explains why when I had a year of D prescription strength supplements, my D dropped from 29 to 14. I wasn't absorbing it at all (and getting sun every day to boot).
Every thing is connected to every other thing...without adequate Potassium, magnesium just sits there, inert. So even if you had enough Mag, but not enough potassium, your body 'thinks' there is no mag, and just excretes the D.
What type of mag do you take? We take citrate. No potassium supps yet though. I will research that more.
I tried mag pills, and they didn't work at all. I learned that long-term mag deficiency can cause absorbtion issues in the gut, which is why the pills were useless to me. I currently take a product called CALM, which is powdered mag that I mix with water, and it absorbs very well. The ingredients panel reads: Ionic magnesium citrate, created from a highly absorbable proprietary blend of citric acid and magnesium carbonate.
The citric acid is important too, as vitamin C is ALSO needed for magnesium, as C is the 'distributor' that moves mag throughout your body. Connections.
I pay $24 retail for a bottle of CALM, which lasts about 2 months. It can be found cheaper online I believe; we have only one health food store and they overcharge a bit.
For Potassium, I am using Cream of Tartar, off the spice aisle. $3 bottle and the body needs such minute amounts, it will probably last me a year or more. It is easy to overdose on potassium, really just need
tiny amounts, so I'm going to emphasize this. The amount of CofT I take is about the same size as a grain of rice. I just mix it in with my water and powdered mag. There are potassium supplement pills, but personally I don't feel they are worth the money, when the Cream of Tartar works just fine. That dosage I take is for me, an adult, currently weighing 220 pounds. If you want to use CofT and want just a tiny amount, just wet the very tip (like 1/8 inch) of the handle of the spoon and dip it in. (it takes a full teaspoon to have too much; I just prefer caution here)
Also, you said in the normal functioning body. I am curious, do you have any info on specific abnormalities where vit d does not absorb properly with sunlight and/or D sups? Anything else beside liver function?
There's calcium levels, copper levels, iodine levels. So much inter-connectedness. I started adding natural iodine in the form of Pink Himalayan sea salt, it comes in it's own grinder like a pepper mill; I add one full twist of salt to my pot/mag cocktail.
Once I started this cocktail- the powdered mag, the cream of tartar for potassium, and the twist of pink Himalayan salt, my D levels came up from 14 to 26 in just 2 months.