What is the Right Amount of Vitamin D Supplementation?

First, it’s important for you to recognize about how much vitamin D you ingest in the foods you eat or absorb through sunlight. If you are not at risk for deficiency and are not experiencing any signs or symptoms of low vitamin D levels, then all you have to do is make sure you get the Institute of Medicine’s (IOM) recommended daily allowance (RDA) of 600 IU for adult males and females between the ages of 9 and 70 years old, or 800 IU daily if you are older.  

On the other hand, if you are at risk or are experiencing symptoms, you should have your vitamin D levels checked by your general doctor or psychiatrist. If your vitamin D level is too low, you can get supplements prescribed and dosed to resolve the issue.

When it comes to these supplements, the IOM states that 20 to 30 nanograms of 25-hydrovitamin D per milliliter (ng/mL) of blood is the minimum needed to maintain bone health. However, the organization does not provide guidance on how to provide vitamin D supplementation to best address other conditions and non-specific symptoms that may be associated with vitamin D deficits. 

It is my opinion that patients who are at risk for these other conditions or who have non-specific symptoms of low vitamin D should take supplements to achieve levels that are higher than the minimal 20 ng/mL. However, they should also be cautious and not allow their levels to go above 50 ng/mL, which may put the body at risk for toxicity.

Some individuals should not take vitamin D supplements at all, as it may cause complications to their health. This includes people with lymphoma and cancers of the bone, sarcoidosis, William’s Syndrome and Granulomatous Diseases, such as tuberculosis.

What are the best Vitamin D treatment methods?

So which form of vitamin D is best? When it comes to raising levels of 25-hydroxyvitamin D, vitamin D3 is the most effective and the most favored form of vitamin replacement.

If you are an adult between the ages of 18 and 70 and do not have psychiatric symptoms or symptoms of vitamin D deficiency, it is important to make sure that you get an RDA of 600 IU of vitamin D3. In my psychiatric office, many patients have their vitamin D levels tested. My goal is to supplement low vitamin D levels in adults aged 18 to 70 to achieve moderate 40 ng/mL 25-hydroxyvitamin D levels, and I have found that patients suffering from depression, aches and fatigue often benefit dramatically within three months of taking adequate vitamin D supplements. If 25-hydroxyvitamin D is between 10 and 20 ng/mL, I will generally supplement with 2,000 to 3,000 IU per day for two to three months, and then retest the patient. If the level is even lower than 10 ng/mL, then I generally recommend 50,000 IU vitamin D per week for 8 weeks and retest before the 8 weeks are up.

For older patients (over the age of 70) who are symptom-free, taking an RDA of 800 IU should be adequate. However, for those who are symptomatic of vitamin D deficiency, supplementation needs to be approached more gingerly, as current literature suggests that there is a U-shaped relationship between serum levels of 25-hydroxyvitamin D and “frailty.”

Vitamin D levels below 15 ng/mL and above 30 ng/mL in older patients have been associated with symptoms of fatigue, weakness, slower walking speed and duration.  Another study suggests that older patients receiving a yearly dose of vitamin D of 500,000 IU actually had an increased rate of falls and bone fractures. 

Taking this information into account, my goal with older patients above age 70 is to keep their levels of 25-hyrdoxyvitamin D levels between 20 and 30 ng/mL, supplementing conservatively and testing regularly.