It depends on your vitamin D levels. For example, if your vitamin D level is 10 ng/ml, and you want to raise your levels to 70 ng/ml, we recommend supplementing with about 10,100 IU daily until you achieve this level.
For most adults, we recommend taking 5,000 IU/day to maintain vitamin D levels between 40-80 ng/ml. If you take 10,000 IU daily for a long period of time, you may be at risk for toxicity. Though, vitamin D toxicity is much more likely to occur if you’re taking 40,000 IU or more daily for extended periods of time.
When your vitamin D levels get too high, hypercalcemia may occur. Hypercalcemia is the condition of high calcium in your blood. The severity of hypercalcemia ranges greatly. Mild hypercalcemia may not have any symptoms; whereas, severe hypercalcemia may result in cardiac arrest or stroke.
It is always best to consult a doctor before supplementing with very large doses.
Hi Amber, I think it’s important to note that the IOM regards 10,000 iu vitamin D3 daily as the safe upper limit for daily supplementation. 5,000 iu D3 daily is so very safe. However, I tend to think actual 25(OH)D blood level matters more than the daily dose. For example, I need to take more than 10,000 iu D3 daily to keep my 25(OH)D blood level at an optimal range. So, I test my blood regularly to ensure that I’m in balance.
Hi Cheryl. It really depends on how high your blood tested. I think that the half life of D is around three weeks. So follow that rule of thumb. VDC please correct me on the half life if it is other than three weeks.