Have vitamin d levels at 37 on a level of 30-100. what is the best form of d to take and does it need taken with anything else?

Although your level of 37 is within the standard low normal range, would prefer to see consistent 50-70 ng/ml blood levels. Obtain Vitamin D-3, and take a maximum of 1,000-2,000 units daily. Recheck in about 3 months. Alternatively, consider 20 minutes of sun without sunscreen 3-4 times weekly, which is less guaranteed but is more natural. Perhaps both?