Boron? What on earth would you do with that? Is it used in some metabolic process somewhere?

edit: Ok, according to "Devirian, T.A. and Volpe, S.L., 2003. The physiological effects of dietary boron."

> Boron is known to influence a variety of metabolic actions. It interacts with calcium, vitamin D, and magnesium, which are all important in bone metabolism. Boron accumulates in bone in concentrations dependent on the amount of boron consumed. Boron has also been found to increase steroid hormone concentrations in postmenopausal women and to have antioxidant properties, which could make it beneficial in preventing atherosclerosis

I would disagree.

https://examine.com/supplements/zinc/#summary1-3

Read the page again about 10% estimated below RDA in the US. Then the RDA is not exactly very well validated and being below it does not mean being deficient.

You can tell if you have zinc deficiency if you have those white dots on your fingernails. Although that's more in the range of "severe deficiency" so if you ever notice that symptom you should try to be more mindful about your zinc intake in the future (food or supplements).

No. White dots on your fingernails can have tons of reasons. It’s more likely that it’s not due to zinc deficiency. [1]

[1] https://en.wikipedia.org/wiki/Leukonychia