What are the side effects of Vitamin D?

In rare cases, you may need to avoid taking vitamin D.

The main side effect of taking too much vitamin D is hypercalcemia, which is too much calcium in the blood. This is because vitamin D increases the absorption of calcium by up to 20x.

It is very rare to have toxic effects of vitamin D. There are several studies out there that state that you would have to consume hundreds of thousands of IU of vitamin D for several months to develop hypercalcemia. In the 1940’s they used 200,000 to 300,000 IU of vitamin D3 to treat TB and rheumatoid arthritis and yes, there were some side effects but they dealt with them.

The whole idea of taking 10,000 IU, or of 20,000 IU being a lot is actually misleading; that’s not as much as you think. If you convert IU into milligrams you will be shocked to see how little that is.

Symptoms of hypercalcemia:

• Kidney stones

• Bone pain

• Excessive urination

• Muscle weakness

• Depression

• Anxiety

A few things to help prevent vitamin D toxicity:

• Vitamin K2 (100 mcg for every 10,000 IU of vitamin D) – vitamin D needs other things like vitamin K2 to work. Vitamin K2 helps keep calcium out of the soft tissues.

• Bile salts – important to help with the absorption of vitamin D.

• Fluid – at least 2.5 liters per day. This should be enough to help keep the calcium from forming kidney stones.

• Magnesium – Magnesium and vitamin D work together. Magnesium is very important in the metabolism of vitamin D.

• Limit dairy – Limit the amount of dairy you consume when you take a lot of vitamin D.

Amounts of vitamin D you may want to consider taking:

• For maintenance: 10,000 to 20,000 IU

• For therapeutic purposes (short-term use): 20,000 to 50,000 IU

When not to take vitamin D:

• Sarcoidosis

• Primary hyperparathyroidism

• Familial hypocalciuric hypercalcemia

• Lithium

• Diuretics (hydrochlorothiazide)

• Certain cancers

• Hyperthyroid