Then there’s the decision of how much supplementation to recommend. If a patient has a level of 20 or lower, Dr. Kaplan advises a dose of 2,000 international units (IU) daily. If a patient’s level is below 10, he’ll start with a pharmaceutical dose of 50,000 units once a week and sometimes even twice a week. He will check levels at four to eight weeks to see if there is any improvement.
Dr. Russell believes that recommendations from the National Osteoporosis Foundation are reasonable; it recommends a dose of 400 to 800 IU for patients under age 50 and 800 to 1,000 IU daily for those aged 50 or older. If a patient is taking 1,000 IU daily and is still low, she’ll recommend taking more—although she notes that patients may feel overwhelmed by the variety of choices they see at the drugstore, with doses ranging from 400 IU to 10,000 IU. She advocates asking patients to report all over-the-counter supplements they take and the dosage to ensure there are no out-of-the-norm dosing issues.
For patients with levels between 20 and 30, Dr. Efthimiou advises a dose of 2,000 to 4,000 IU daily, along with an appropriate diet. Although supplementation is the most often recommended route to boost vitamin D, eating certain foods, such as fish, milk and eggs, can also improve vitamin D levels.
And what about sun exposure? It may not be music to a dermatologist’s ears, but some clinicians also recommend brief sun exposure to boost absorption. Dr. Troum recommends 10 minutes of sun exposure daily without sunscreen, if it’s not contraindicated, because it can be in patients who have had skin cancer. Still, the idea of sun exposure for vitamin D is always a push/pull, with the dermatologists treating patients as well, Dr. Wei says.
Another population that may want to stick with supplements is lupus patients, because they tend to be photosensitive, Dr. Kaplan says. Their vitamin D levels tend to be low, but it’s not clear if that’s because they often avoid the sun and, thus, have low levels or because lack of the vitamin exacerbates lupus, he says.
Vitamin D has many benefits, but Dr. Kolasinski says it’s important not to overestimate the benefits of any single vitamin or supplement.
What Needs Further Research
There are still many questions that rheumatologists would like answered about vitamin D.
One major question is whether increasing vitamin D in patients with insufficient levels, either with diet or supplements, can improve outcomes in patients with autoimmune disease, such as RA or lupus, Dr. Troum says. Randomized controlled trials with supplementation would be helpful to answer this question.
