One of my unorthodox views is that the popular blue light obsession is exacerbated by magnesium deficiency, given how hard it is to get enough in our diets.
Yes, blue light disrupts melatonin and makes it harder to get to bed. But magnesium disrupts sleep quality and deregulates melatonin production in the first place and makes one particularly sensitive to blue light.
Melatonin production is influenced at least also by: Zinc, iron, calcium, copper, P5P (active B6), and tryptophan. Selenium, iodine, and manganese are involved in indirect ways. Many people are deficient in most, or all of those.
To be fair, some of these, like iodine and selenium, have always been problematic in some regions, like Switzerland (lots of goiters). But I find it less than ideal that only some minerals are fortified in bread and milk etc, because their deficiency is very obvious. While all the other minerals are not fortified because their deficiencies are less obvious or less well understood.
A healthy human body contains quite a few minerals in greater abundance than iodine: copper, bromine, strontium, rubidium, gallium, silicon, zinc, iron, and the electrolytes. Some of them don’t even have lab tests (not that blood tests work well for minerals, which is another issue - blood is short term transport for most minerals, not storage).
Magnesium is also a mineral that is under supplied by multivitamins due to the bulk required. This is why I take a magnesium supplement on top of a multivitamin. Given the state of vegetables today it seems wise and I feel much better with it.
Yes, blue light disrupts melatonin and makes it harder to get to bed. But magnesium disrupts sleep quality and deregulates melatonin production in the first place and makes one particularly sensitive to blue light.