I am 30 years old male. I recently underwent health check-up. It was found that, "25-OH Vitamin D" value is very low i.e. 6.2 ng/ml. Method used for testing is C.L.I.A. As per report, Ranges are specified as below- Deficiency:< 20 ng/ml, In sufficiency: 20-30 ng/ml sufficiency: 30-100 ng/ml Vitamin B12 level is 268 pg/ml which seems to be in normal range (211-911pg/ml) as per report. Looking at these ranges, I seem have Vitamin D deficiency. I also feel less energetic all the time. Can it be because of this deficiency? Do I need to take Vitamin D supplements? Please suggest the dosage!