Mineral assimilation is affected by pH

Minerals have different pH levels at which they can be assimilated into the body. Minerals on the lower end of the atomic scale can be assimilated in a wider pH range, and minerals higher up on the scale require a narrower and narrower pH range in order to be assimilated by the body.

It narrows somewhat for Calcium and Potassium
Narrows more for manganese and iron
More for zinc and copper
More for iodine
For example, sodium and magnesium have wide pH assimilation ranges.

Iodine, which is high up on the atomic scale, requires near perfect pH for its assimilation into the body.
Iodine is one of the most important minerals for proper functioning of the Thyroid, but it doesn't get access to iodine unless the body pH is near perfect.

Perfect total body pH = 6.4

How to calculate body pH: ((2xSaliva pH) + Urine pH)/3

This work comes courtesy of Dr. Carey Reams (Reams Biological Theory of Ionization), an absolute genius with fluid dynamics.