I take 2000iu of vitamin d and drink milk yet my vitamin d was only 28. normal range is 30-100 according to lab. what would cause the low level?

Vitamin D : A higher dose may be needed. Absorption can be impeded by certain medications. Vitamin d3 is superior. A liquid or chewable formulation can be tried. A little of daily sun exposure may help.

Insufficient dosage: While many authorities recommend a paltry 600 iu/day, scientists have found most adults need to take about 5000 iu/day to achieve optimal levels (being 50-90).Your experience is confirmation of this!take 5000 iu/day & recheck levels in a few months. See http://www.Vitamindcouncil.Org/about-vitamin-d/how-do-i-get-the-vitamin-d-my-body-needs/ & http://www.Mercola.Com/article/vitamin-d-resources.Htm.

May need Mg also: Along with my colleagues' suggestions for higher dose of vit d, you may also need more magnesium (mg). Mg is needed to convert vitamin d into its active form. Also all the enzymes metabolizing vit d require mg as a cofactor. Eat lots of vegetables, nuts and seeds; you can also take a mg supplement (malate, citrate, etc) 200-400 mg/day. Doing this may successfully increase your vit d level.