Vitamin D, which is really a hormone is more and more getting attention as a fundamental piece of the health puzzle.

Studies show low levels can disrupt sleep patterns, decrease bone density, increase the risk of certain cancers, and destabilize mood.

Especially if you live above the 37th parallel it is vital to supplement as even on sunny days during the winter you don't get any Vitamin D at all.

If you live below the 37th parallel and are never outside also consider supplementing.

It is vital to get tested at least once a year to check in on your D levels. The test is called Serum oncentration of 25(OH)D.

According to the NIH here are the ideal levels of D:

Table 1: Serum 25-Hydroxyvitamin D [25(OH)D] Concentrations and Health* [1
nmol/L** ng/mL* Health status
<30 <12 Associated with vitamin D deficiency, leading to rickets in infants and children and osteomalacia in adults
30–50 12–20 Generally considered inadequate for bone and overall health in healthy individuals
≥50 ≥20 Generally considered adequate for bone and overall health in healthy individuals
>125 >50 Emerging evidence links potential adverse effects to such high levels, particularly >150 nmol/L (>60 ng/mL)

 Read up on the following Vitamin D3 liquid supplements and stock up before the colder months.