Vitamin D3 125mcg (5000 IU) by Pure Encapsulations

This dose fits adults whose Vitamin D, 25-Hydroxy is low or in the lower end of normal and who want a time-limited repletion plan. It’s a practical pick if you get little sun, have darker skin, use sunscreen consistently, live at northern latitudes, have higher body weight, or have malabsorption (celiac, bariatric surgery, inflammatory bowel disease). If your level is very low, you may need a clinician-directed loading phase first, then step down. For long-term maintenance once replete, many do better with lower daily vitamin D3.

Cholecalciferol (vitamin D3) is the form your skin makes from sunlight and is generally more effective than D2. Your liver and kidneys convert it into the active hormone that increases calcium absorption from the gut and helps regulate bone turnover. Adequate D3 keeps parathyroid hormone (the signal that pulls calcium from bone) in check, which preserves bone density over time. Interest in D3 for immunity and mood is high, but effects are modest and clearest in people who were deficient to begin with.

Take one capsule daily with a meal that contains fat; absorption is better with dietary fat. Recheck Vitamin D, 25-Hydroxy in 8 to 12 weeks and adjust. If you overshoot and your Calcium runs high on labs or you develop symptoms (thirst, frequent urination), stop and contact your clinician. Once your level is in a comfortable range, shift to a maintenance dose, often 1,000–2,000 IU daily depending on sun exposure and body weight.

Thiazide diuretics (water pills for blood pressure) plus vitamin D3 can raise Calcium too high; monitor if used together. Orlistat and bile acid sequestrants like cholestyramine reduce absorption—separate dosing by several hours. Long-term steroids and some anti-seizure drugs lower vitamin D status, which can justify this dose with lab follow-up. Combine with high-dose calcium only if your labs and diet suggest you need it, to avoid high calcium.

Avoid unsupervised vitamin D3 if you have a history of high calcium, recurrent kidney stones, primary hyperparathyroidism, or granulomatous diseases like sarcoidosis or tuberculosis (these can overproduce active vitamin D). Pregnancy and breastfeeding are generally fine with vitamin D, but dosing should follow your clinician’s plan with periodic Vitamin D, 25-Hydroxy checks.